Saturday, July 31, 2010

July 31: Heat Returns Next Week

Blog Updates:

- Invest 90L now has a 60% risk of developing into a tropical depression or storm. For more information on 90L, as well as severe weather over the next 2 days, go to the Severe Weather / Tropics page.
- The latest 5-Day Forecast has been updated for the immediate NYC area and the interior area.

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Today was another much needed cool day, with high temperatures again in the upper 70s to mid 80s. Today though was the last sunny and chilly day for a while, as clouds and rain return to the forecast tomorrow, with heat and humidity already returning by Tuesday.

Tomorrow's Outlook:

Tomorrow should be cloudy across most of the area, with a SSE wind expected. High temperatures are expected to peak in the upper 70s to lower 80s across the area, though places that see more rain could end up slightly cooler.

Meanwhile, a disturbance approaching the area should bring widespread light to moderate showers and thunderstorms, with locally heavy rain possible. The rain should stay far west enough so that Long Island has a lower chance of rain for Sunday, but more rain is possible for Sunday night for Long Islands. The latest models, however, significantly backed away from the heavy rainfall amounts, only showing up to 1/4 inch. While I expect slightly higher rainfall amounts, I did slightly lower the forecast rainfall amounts for the area.

Next Week: Hot, Humid And Stormy

Monday will continue with the chilly temperatures and rain, however the rain should not be as widespread or as heavy as it should be on Sunday. High temperatures in the upper 70s to lower 80s are expected again. Tuesday will also bring partly to mostly cloudy skies with an isolated shower or two, however temperatures should be much warmer, in the mid 80s inland and in the upper 80s for the immediate NYC area.

By Wednesday, the next cold front approaches, however it is likely to be slow moving, with its effects lasting through Thursday. The models continue to be uncertain with the timing, however thunderstorms are likely for Wednesday and Wednesday night, with Thursday also potentially bringing some storms in the slower solution. Whether there is a severe weather potential or not, the models are showing high precipitable water values, over 2 inches, which combined with the slow moving cold front, could bring a heavy rain threat for that time frame. Wednesday should be the warmest day, with highs in the upper 80s inland and the upper 80s to lower 90s for the immediate NYC area, with Thursday slightly cooler.

Behind the cold front, the air mass is likely to stay relatively warm. High temperatures should continue to stay in the mid to upper 80s inland and the upper 80s to potentially lower 90s for the immediate NYC area.

Longer Range: Potential Heat Wave?

Beyond Days 5-7, especially in the summer, there is usually more uncertainty with the forecasts, though the models can give an idea of the expected pattern. For the last 3 days, the ECMWF and GFS models were relatively consistent in bringing yet another heat wave to the area starting next weekend, around Saturday/Sunday. The 18z GFS was the most extreme, with a 7-day heat wave with temperatures near 100 degrees, and while that solution is unlikely at this time, the models may be hinting that another heat wave may be on the way for the longer range. Stay tuned for more details on this potential should it reach the medium range.

Friday, July 30, 2010

July 30: Rainy Sunday And Monday

Blog Updates:

- My August Outlook has been posted in the Long Range Forecasts page, expecting above average temperatures and slightly above average precipitation.
- The latest on the tropics, as well as any severe weather in the next 2 days is included in the Severe Weather/Tropics page, which was updated tonight.
- The 5-Day Forecast has been updated for the area, with the potential rainfall amounts for Sunday and Monday for each part of the area.

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Today was a very chilly day compared to the rest of this month, with high temperatures only in the upper 70s to mid 80s across the area, which despite being only slightly below average, is actually one of the coolest days of the month. These comfortable conditions should continue through tomorrow, however things get more unsettled afterwards, with a storm that should bring rain and chilly temperatures to the area.

Tomorrow's Outlook:

Tomorrow should be a little more chilly than today, but with more sunshine expected. High temperatures should be in the upper 70s to lower 80s inland and for S CT and Long Island, with lower to occasionally mid 80s for the immediate NYC area. A NNE turning ESE wind is expected throughout the day.

No rain is expected for the area, however rain will slowly approach the southern and western parts of the Mid Atlantic. These storms will later affect the area on Sunday and Monday, bringing locally heavy rain.


Sunday And Monday: Rainy, Chilly

As mentioned above, a storm will slowly approach the area on Saturday night, and affect the area between Sunday and Monday. Rain and some thunderstorms are likely to overspread the area during Sunday morning to late afternoon, with chilly high temperatures, in the mid to upper 70s for most of the area but slightly warmer for the immediate NYC area.

The models continue to be uncertain with the rainfall amounts, with some keeping it to our south, others bringing up to 1/4 inch, and others producing 1-2 inches. There should be a high pressure close to New England, which will prevent the rain from reaching that area, however if the high pressure is close enough, it may also prevent the area from seeing anything more than some light rain.

At this time, I am expecting occasional light to moderate rain and thunderstorms between Sunday and Monday, producing locally heavy rainfall, with the potential for the heaviest rainfall on Sunday night. Most of the rain should be focused on the western parts of the area, with some rain but not as heavy further east. Rainfall amounts should generally range from 1/4 to 3/4 inch, with the highest amounts in western NJ and Orange County, with up to 1.5 inch possible in the heavier showers.

Next Week And Longer Range: Heat, Humidity Return

After the storms move out, Tuesday should bring the return of heat and humidity, with high temperatures returning into the mid to upper 80s inland, and the upper 80s to potentially lower 90s for the immediate NYC area. With partly cloudy skies, there is a slight chance of a shower or thunderstorm, however that is unlikely at this time.

A cold front should affect the area on Wednesday. A warmer air mass should spread into the area for the day, bringing high temperatures into the lower 90s for the immediate NYC area, however the worst of the heat will stay to our south, where a significant heat wave over the southern US with 100+ degrees should spread into the southern and potentially central Mid Atlantic. Meanwhile, the front is expected to move through on Wednesday night. There is still uncertainty with the exact timing, with solutions ranging from Wednesday afternoon to Thursday morning, however at this time, scattered thunderstorms are likely, some of which could reach strong to severe levels if the slower solution verifies. More details on this potential will come once details become clearer.

The cold front is likely to slow down once it moves offshore, and if some model solutions verify, it may even stall to our east. The air mass behind the cold front will not be much cooler, with mid to upper 80s likely to persist for the end of next week.

Thursday, July 29, 2010

July 29, 2010: Colder Temperatures Return

Notes: The 5-Day Forecast and Severe Weather/Tropics pages have been updated, including details about Invest 90L.

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A cold front moved through the area earlier today, bringing a temporary end from the heat and humidity as the wind changed direction towards the NW with dropping humidity. Most of the area saw light rain this morning, with a few locally heavy thunderstorms for southern New York City earlier this afternoon. The worst of the severe weather, however, was focused over southeastern Virginia, where widespread strong to severe thunderstorms produced tornado warnings and dumped several inches of rain.

Temperatures are going to be much cooler starting tomorrow, with near to slightly below average high temperatures likely, but these cool and dry conditions will not last for long, as more rain chances return by Sunday, as well as the return of warmer temperatures for next week.

Tomorrow's Outlook:

Tomorrow will be partly sunny across the area. High temperatures will be much cooler than today, in the lower to occasionally mid 80s inland, and the mid to occasionally upper 80s for the immediate NYC area. Long Island and S CT, with a NNW wind, should reach the lower 80s.

Tomorrow night should also be chilly, with low temperatures expected to drop into the mid to upper 50s inland, lower to mid 60s for the immediate NYC area, and the upper 50s to lower 60s for Long Island and S CT. The cooler spots in east central Long Island should be slightly cooler.

Saturday - Monday: Chilly, Some Rain

Saturday will be the last of the comfortable and chilly days for a while, with slightly cooler temperatures than tomorrow. High temperatures will be in the lower to mid 80s across the area, with the wind direction turning towards the east. Saturday night should not be as chilly as tomorrow night with increasing cloud cover.

Rain is likely to return for the area on Sunday and Monday. The models still have different solutions, some showing a suppressed coastal low with no rain for the area and heavy rain to our south, and others showing scattered yet heavy showers and thunderstorms. At this time, I am expecting scattered showers and thunderstorms, mainly on Sunday night, some of which could produce heavy rainfall. High temperatures in this solution would be in the upper 70s to lower 80s across the area for both days.

This is not a final solution yet, and can still change. Stay tuned for more details over the next few days.

Next Week: Hot, Humid Conditions Return

Behind this area of storms, temperatures should warm up again with more humidity, with high temperatures back into the mid to upper 80s inland, and the upper 80s to lower 90s for the immediate NYC area. Dry conditions are expected for Tuesday, however by Wednesday, a cold front should move through, bringing the next risk of thunderstorms and potentially severe weather to the area. There is still uncertainty with the timing, with some models bringing the cold front through in the morning and others in the afternoon, however thunderstorms are likely for Wednesday at this time, with even hotter and more humid conditions possible in the slower scenario. Stay tuned for more details on this time frame.

July 29, 2010 Morning Update

10:16 AM: An area of light to moderate rain and storms moved through earlier this morning, bringing at least a trace of rain to most of the area, with up to 1/2 inch in western New Jersey. The cold front has not moved through yet, and the potential of additional storms continues until the early afternoon hours.

The line of storms can already be seen in central PA, and is rather weak and scattered. This may bring an additional chance of storms later today, however the highest chance of severe storms remains to our south, where I added a 15% risk for parts of the eastern Mid Atlantic today, as well as a 10%, potential 15% risk for parts of West Virginia and Virginia. The CAPE and shear parameters are not too bad, however there are factors that will limit the severe weather threat in that area, including cloud cover and unsupportive timing. For the NYC area, no severe weather is expected, though locally heavy rain is possible with the storms.

If needed, storm updates will be posted between 2 and 4 PM. Otherwise, the next update will be posted tonight, with more details about Sunday and Monday's potential rain event and what happens afterwards.

Wednesday, July 28, 2010

July 28: Cooler Weather Starts Friday

Blog Updates: Both the 5-Day Forecast and the Severe Weather/Tropics pages have been updated today.

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Today was again a mainly sunny day, however temperatures were warmer across the area, returning into the 90s for the immediate NYC area. This isn't likely to last for long, however, as a cold front moving through tomorrow will bring cooler temperatures to the area that will last for a few days.

Tomorrow's Outlook And Storm Potential:

A cold front is expected to move through late tomorrow morning or the early afternoon hours. It appears that the cold front's timing will not be supportive for severe weather, however with precipitable water values near 2 inches, locally heavy rainfall is a possibility with an area of storms likely to move through during the morning hours inland, late morning to early afternoon for NYC, and afternoon hours for Long Island/S CT.

High temperatures will be slightly cooler than today, with humid conditions likely early in the day. High temperatures will reach the mid 80s inland, upper 80s to lower 90s for the immediate NYC area, and mid to upper 80s for Long Island and S CT.

Friday And Weekend: Chilly, Then Rainy

Friday and Saturday will both be much cooler and less humid, with high temperatures dropping into the lower to mid 80s inland and for Long Island/S CT, with mid 80s likely for the immediate NYC area, with a few upper 80s possible. Dry conditions are expected for both days.

Rainy conditions return again by Sunday as a disturbance approaches the area. Scattered showers and thunderstorms are likely between Sunday and Monday, some of which could produce heavy rain. The GFS model, which has been updated with new features today, shows 1-2 inches of rain for the area, though this may be too much. High temperatures will be in the upper 70s to lower 80s across the area for both days.

After the rain moves out, a warmer air mass returns once again. High temperatures will reach the upper 80s to lower 90s again, with the next potential of rain for late next week.

Tuesday, July 27, 2010

July 27, 2010: Rain Chances On Thursday, Sunday

Today was a much nicer day across the area, with partly sunny skies and high temperatures in the mid 80s to lower 90s across the area. Tomorrow will be slightly warmer, however more rain returns for Thursday, as well as Sunday.

Tomorrow's Outlook:

Tomorrow should be warmer than today, as a cold front approaches from our west, with increasing humidity. High temperatures will rise into the upper 80s inland, and the lower to mid 90s for the immediate NYC area. With a SW wind, S CT and Long Island will reach the mid to upper 80s.

For tomorrow night, mostly cloudy skies are expected as well as increased humidity as low temperatures drop into the upper 60s to 70s. An isolated shower or thunderstorm could be possible, especially after midnight.

Thursday's Outlook: Stormy Conditions Return

By Thursday, the next cold front should affect the area. The model solutions have not trended slower, and in fact some models have trended faster, with the GFS already showing the heavier rain offshore by noon. It is still faster than the other models, and I continue to lean towards the slower solutions, however a severe weather potential isn't too high at this time, with unsupportive timing, too much cloud cover, and the lack of widespread high shear. With high precipitable water values, however, heavy rain will be a threat as a line of rain and thunderstorms moves through in the late morning to early afternoon hours. The highest severe weather potential will stay to the south and east of the area.

Longer Range: Chilly, But Rain Returns

For Friday, temperatures will significantly cool down, with high temperatures falling into the lower to mid 80s with a few upper 80s possible, and low temperatures in the 50s inland and 60s elsewhere. Saturday should be the same, however the next rain chance returns by Sunday afternoon. A disturbance is expected to bring scattered showers and thunderstorms for Sunday and Monday, which would keep high temperatures down into the lower 80s, however some models are showing a heavy rain possibility, with 1-2 inches of rain, including the parallel GFS, DGEX and ECMWF. This potential is still uncertain, and more details will come as details become clearer on this storm, and if a heavy rain potential will be present or not.

Monday, July 26, 2010

July 26: Storms Return For Thursday

Blog Updates:

- This past week was very active for the area, with several rounds of severe thunderstorms. A summary of these storms has been posted in the Storm Summary page, as well as yesterday's confirmed tornado in Bronx.

- The 5-Day Forecast page has been updated tonight.

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The very active week came to an end yesterday, with yet another severe thunderstorm that brought widespread wind damage from Bergen county, NJ to Westchester county and Bronx, into Long Island. The NWS confirmed that there was an EF-1 tornado in Bronx yesterday, which was only the 2nd tornado in the Bronx since 1950. Fortunately, with the cold front that moved through, today was a much quieter day for the area, with no rain expected until Thursday.

Tomorrow's Outlook:

Tomorrow will be another very nice day for the area, with low humidity again. High temperatures will be in the upper 80s for the interior (NW NJ and Orange County), in the upper 80s to lower 90s for the immediate NYC area (NYC, western Long Island, NE NJ, Rockland/Westchester counties), and for southern Connecticut and Long Island, temperatures will rise into the mid to upper 80s with a WSW wind.

Most of the Mid Atlantic and Northeast will stay dry once again, with mainly sunny skies, however Virginia and parts of Maryland will not be dry, with scattered thunderstorms possible.

Wednesday And Thursday: Humidity And Storms Return

By Wednesday, humidity is expected to increase once again with partly sunny skies. High temperatures are expected to reach the upper 80s to lower 90s inland, lower 90s for the immediate NYC area, and for Long Island and S CT, temperatures should reach the mid to upper 80s, however temperatures for parts of Long Island could be slightly cooler, especially with a SSW wind. I would not be surprised if parts of the immediate NYC area reach the mid 90s for Wednesay.

For Wednesday Night, temperatures will cool down into the upper 60s to lower 70s inland, and in the 70s for the rest of the area, however it will become even more humid, with dew points back into the upper 60s to lower 70s. The NAM model shows a thunderstorm potential for late Wednesday night into early Thursday morning, and with the NAM being more reasonable with the cold front timing, I mentioned this potential in the 5-Day Forecast.

Thursday will be another hot and humid day, but with the next cold front, comes the next risk of strong to severe thunderstorms. Most of the models continue to be fast with the timing, showing the cold front moving through on Thursday morning, however they have also been too fast for previous cold fronts. Yesterday's storms are an example of this, as 4 days earlier, the models showed the cold front moving through on Saturday, with Sunday being dry. I continue to expect the models to trend slower, with Thursday potentially being a favorable day for severe weather for the Mid Atlantic up to NYC, potentially including the southern Northeast if the timing is supportive. More details will come on this storm potential tomorrow, as well as a severe weather potential risk map.

Friday And Longer Range: Colder Temperatures Return

Unlike the previous cold fronts that moved through the area, which kept temperatures in the upper 80s to lower 90s, this cold front is likely to cool down the area, with high temperatures in the lower to mid 80s with a few upper 80s for Friday and Saturday. Low temperatures will generally be in the 50s inland, and the 60s for the immediate NYC area, southern CT and Long Island.

Sunday is expected to be slightly warmer as a warmer air mass approaches from the west. For Sunday night into Monday, however, as the warmer air mass continues to push into the area, scattered showers and thunderstorms may be possible, as well as increased humidity. Stay tuned for more details on this storm potential.

Sunday, July 25, 2010

July 25, 2010: Temperatures To Cool Down For Now

Note: The 5-Day Forecast page has been updated today.

Today brought a round of heavy thunderstorms for most of the area, bringing an end to the very hot and humid conditions the area has seen in the last few days. This change will be temporary, however, with temperatures already warming up by the middle of this coming week.

Tomorrow's Outlook:

Monday will be much more comfortable than today. It will still be warm, with temperatures in the mid to upper 80s inland, upper 80s for the immediate NYC area, and with a NW wind, Long Island and S CT should warm up into the mid to upper 80s, but there will be much less humidity, with dew points dropping into the 50s to lower 60s.

No rain is expected across the Mid Atlantic and Northeast tomorrow as a high pressure will be in place, with today's storm well offshore.

Tuesday - Thursday: Hot, Humid And Stormy Conditions Return

Tuesday will still be a calm day across the area, with temperatures slightly warming up into the upper 80s to lower 90s for the immediate NYC area, upper 80s inland, and with a WSW wind, Long Island and S CT will reach the mid to upper 80s again. Meanwhile, the next storm will slowly approach the area.

By Wednesday, slightly more humid conditions are expected, with temperatures in the lower 90s for the immediate NYC area, upper 80s inland, and the mid 80s for Long Island and S CT with a SSW wind expected.

Wednesday night will be humid again as the next cold front approaches, with low temperatures in the upper 60s to 70s across the area, however an isolated shower or thunderstorm is possible, especially in the western parts of the area.

By Thursday, the computer models continue with the uncertainty, some bringing the cold front through on Thursday morning. As I mentioned yesterday, however, the models tend to be too fast on cold fronts looking at the last few storms, and at this time, I am expecting the timing to trend slower, with the cold front moving through between Thursday afternoon and evening. As a result, this could bring a risk of strong to potentially severe thunderstorms to the area, which I mentioned in the 5-Day Forecast. More details will come on this storm potential as details become more clear.

Friday And Next Weekend: Cooler, Less Humid

A colder air mass will move into the area by Friday, bringing cooler and less humid conditions to the area. The models continue to be colder with this air mass, with highs in the 70s and lows in the 50s, however they have been too cold previously, and at this time I am expecting high temperatures in the lower to upper 80s, with lows in the 50s inland and 60s for the rest of the area.

July 25, 2010 Storm Updates

4:51 PM: The rain is now ending across northern New Jersey and SE NY. There is still light to moderate rain in NYC and parts of Long Island and southern CT, which will continue to move east to ENE, ending over the next 1-3 hours.

The storm coverage has ended for today. The 5-Day Forecast page will be updated tonight. A brief update may be posted around 6 PM, which would include more details about the next potential of rain, as well as the potential cool down to follow.


3:58 PM: ***WARNING: A Tornado Warning is in effect for Suffolk County, NY***. The severe storm is now in central Long Island, moving SE. This storm is going to keep moving SE, and should move offshore within the next 20-40 minutes. It is still capable of producing very heavy rainfall and strong wind gusts. Moderate to locally heavy rain is now spreading into north central and NE NJ, and should continue to move ENE, spreading into SE NY and SW CT, as well as NYC and western Long Island.

In addition, NYC is currently dry, however rain should start again in the next few minutes. This dry slot will keep moving east, into Long Island.


3:24 PM: The severe storm is currently over southern Westchester county, moving east. This storm is still producing very heavy rainfall with low visibility, as well as strong wind gusts and small hail. Over the next hour, this storm will move through northwestern and central Long Island, producing up to an inch of rain in a short period of time.

There is now light to moderate rain falling over northern NJ and southeastern NY. This rain will continue for the next few hours, with an additional 1/2 inch of rain possible. In addition, there is a strong storm intensifying in southern Bergen county moving ENE, with another round of heavy rain in west central NJ, to approach the immediate NYC area within the next hour. Parts of northern New Jersey could end up with as much as 2 inches of rain by the time that this storm ends.


2:48 PM: The storm approaching eastern Bergen county is potentially producing small hail and gusty winds, however heavy rain continues to be the main threat with this storm, with up to 1 inch of rain possible in a short period of time.

Meanwhile, across the rest of the area, heavy rain is moving into Westchester county, as well as southwestern CT. Light to moderate rain is also moving into Staten Island. Over the next hour or two, rain and thunder should spread into most of the area, with light to moderate rain expected for the rest of this afternoon and evening, however, no severe weather is expected, as the parameters are not supportive. The highest risk of severe storms today is from southern PA/NJ and further south.


2:35 PM: There is a strong thunderstorm in eastern Passaic and western Bergen county, moving southeast. This storm is producing very heavy rainfall, with a history of producing 1-1.5 inches of rain, with strong wind gusts also possible. This storm is going to affect Bergen county, Rockland county, and parts of Westchester and Bronx counties within the next 30 to 60 minutes.

Saturday, July 24, 2010

July 24, 2010: More Storms For Tomorrow

Note: The 5-Day Forecast has been updated tonight.

Tonight's Storm Potential:

As I mentioned was a good possibility in my previous update, the two areas of storms have split, with one area staying to the north of NYC and the other to the west and just to the south of NYC. As a result, the most likely areas tonight to see storms are interior SE NY and south/central CT, where I have a higher risk of thunderstorms in the 5-Day Outlook. Another area likely to see storms will be for west central New Jersey and areas south of NYC, however it is possible that these storms manage to move through parts of southern NYC. northern NJ and parts of Rockland county, NY should see an area of light rain, but no severe storms.

Tomorrow's Outlook:

Tomorrow should, be slightly cooler than today, however it will still be quite humid, especially earlier in the day, and temperatures will still reach the lower to mid 90s for the immediate NYC area, and the upper 80s for interior areas. Mostly cloudy skies are generally expected across the area, but if there will be thunderstorms during the early afternoon, it could end up being slightly colder.

There is also a severe thunderstorm potential tomorrow, as the cold front moves through, ending the heat and humidity for now. While the best parameters are mainly to our south according to the latest models, there are still some strong to severe thunderstorms possible, especially during the afternoon hours, as a line of storms moves through. For now, I expect the area to be in the northern end of the 15% risk for tomorrow. If needed, storm updates may be posted between 2 and 6 PM tomorrow.

Next Week's Outlook

Monday and Tuesday will already be cooler and less humid. Monday should be the coolest day, with high temperatures in the mid to upper 80s inland and the upper 80s for the immediate NYC area, with Tuesday slightly warming up, with lower 90s possible for the immediate NYC area. No rain is expected during this time period.

For Wednesday, a warmer air mass once again returns into the area, with temperatures warming up into the lower 90s again, as a cold front approaches from our west. It is likely to move through on Thursday, however its timing is still uncertain. The latest model solutions have it moving on Wednesday night, however they have been too slow for this storm and previous storms, and may very well trend slower. For now, I am going slower than the models, expecting a thunderstorm risk for Thursday and Thursday night, with highs in the lower to potentially mid 90s.

Friday and next weekend are expected to be rather chilly, with temperatures cooling down into the mid to upper 80s, however temperatures should warm up again by the end of the weekend or Monday.

July 24, 2010 Evening Update

9:06 PM: There are two separate areas of storms currently active, the first being in central NY and the second in north central PA. The area of storms in central New York is currently moving east to ENE, taking it towards east central NY and western New England, the areas highlighted with a 15% risk of severe weather in my outlook for today. These storms are strong to severe, and while most of them should stay to the north of the area, some of these storms are likely to affect the northern parts of the area, including southeastern NY and south/central Connecticut. There is also a band of light to occasionally moderate rain ahead of this line of storms, which is about to enter Orange County, and should continue moving ESE from there.

The second area of storms is in north central Pennsylvania, and moving SE. This area of storms is severe, and is likely to spread into most of central and southern Pennsylvania. It may approach the southwestern parts of the area, towards west central New Jersey.

What happens for NYC, however, is still uncertain and could change at any time. These two areas of storms are moving in two different directions, but they are still connected around NE PA, with scattered severe storms in that area. What is uncertain is whether these two areas of storms stay connected, or if they split. If they split, the immediate NYC area is likely to stay mainly dry with an isolated storm or two. If they stay connected, however, another round of strong storms may be possible for the immediate NYC area. More details will be posted on this either later this hour, or with tonight's 10 PM update.

Friday, July 23, 2010

July 23: More Storm Tomorrow, Heat Returns

A severe thunderstorm has just went through northern New Jersey into New York City, producing a wide path of hail and damaging wind gusts. This, however, is not the end of the severe weather potential, as things only become even more active. Tomorrow, in addition to being one of the hottest days of the year, will also bring a severe weather risk to parts of the area.

Tonight's Outlook:

Tonight will continue to be mild and humid, with low temperatures only dropping into the mid to upper 70s across the area. There is an area of storms in western NY and PA which may approach our area, and while it is uncertain whether it affects us or not, the NAM and RUC models have been consistently showing storms for tonight, and if these solutions verify, another round of storms may be possible for late tonight.

Tomorrow's Outlook:

Tomorrow will be a very hot, humid and uncomfortable day. With partly cloudy skies, high temperatures wil rise into the mid 90s inland, and the upper 90s for the immediate NYC area, with a few places possibly reaching the lower 100s if there is enough sunshine. With dew points in the 70s, it will feel like the mid to upper 100s.

There is, however, the potential that the temperatures would not be as high as expected. As the warm front will stay to our north, there is a thunderstorm risk from southern Michigan and northern Indiana/Ohio, through central NY/PA and into southern New England. The highest risk of severe storms will be focused in southern Michigan and northern Indiana/Ohio, as the parameters are the most supportive in these areas. Further east, there will be a general 15% severe thunderstorm risk, as the parameters are relatively supportive, but not as much as places further west.

The corridor of storms for tomorrow is expected to be in northern PA and southern NY into southern New England, however more cloud cover is expected for the northern parts of the area tomorrow, also where the best chance of a severe thunderstorm is, with at least a 15% slight risk. The risk of strong to severe storms in the area should start from the afternoon hours, and should focus on the northern parts of the area, with the main threat being strong wind gusts. If needed, storm updates will be posted between 3 and 5 PM tomorrow.

Sunday's Outlook: Hot, Humid And Stormy

Sunday will be the last of the hot and humid days. With Saturday night likely to be mild and humid, with temperatures in the mid to upper 70s inland and the upper 70s to lower 80s for the immediate NYC area, Sunday will continue with the heat and humidity, with high temperatures in the upper 80s to lower 90s inland, and the lower to mid 90s for the immediate NYC area. The severe weather risk, however, is much lower than tomorrow, especially with much lower parameters. At this time, a 5% risk of severe weather is expected for Sunday, with scattered storms, a few which could reach strong to locally severe levels.

More on the longer range will come on tomorrow's update, which will focus on that.

July 23, 2010 Storm Updates

9:12 PM: The severe thunderstorm is currently over Queens, and continues to move SE. This storm continues to weaken, and is expected to produce heavy rain, as well as gusty winds and potentially small hail for places near and east of JFK airport. There is also an area of heavy rain near SE CT, which is moving SE and offshore.

As I am working on tonight's post, the storm coverage has ended for today. Tonight's post will be posted by 10 PM, with more details on any storm potential tomorrow and Sunday.


8:50 PM: The Tornado Warning has been cancelled for the immediate NYC area, however a severe thunderstorm warning is still in place for New York City. The storm has weakened, however it is still capable of producing small hail and gusty winds for Manhattan, Queens and western Long Island, including places just north and east of JFK airport.


8:20 PM: ***WARNING: All of Manhattan, northern Brooklyn and western Queens are now under a Tornado Warning***. The storm has slightly weakened, however it is still capable of producing moderate sized hail, damaging wind gusts and a potential tornado as it continues moving southeast.




7:59 PM: ***WARNING: A Tornado Warning is in effect for southern Bergen, eastern Passaic and Hudson counties in NJ***. A severe storm capable of producing damaging wind gusts and large hail, as well as a potential tornado, is currently in central Passaic county, moving southeast. The areas mentioned above are in this storm's path, with southern Manhattan and Brooklyn also in the storm's eventual path. Places to the north of that axis will get heavy rain and thunder, but no severe storms.

July 23 Afternoon Update

The area of rain mentioned in yesterday's update ended up being further south than expected, which brought at least light rain to most of the area, with the heavier rain amounts focusing on northern NJ and the northern parts of the area. Rainfall amounts generally ranged from less than 0.1 inch in Long Island, to 0.1 to 0.5 inch for northern NJ, SE NY, and southern Connecticut. There are still some weak storms active over the eastern parts of the area.

Meanwhile, there is a small severe weather potential for later this afternoon. It is currently mostly cloudy and chilly across most of the area, with temperatures in the 70s. With sunshine expected for the next few hours, temperatures should rise rather quickly, into the 80s with a few lower 90s possible.

Looking at the radar above, there is an area of severe thunderstorms currently entering western NY, which should move on to affect parts of Pennsylvania, moving east at first then slowly turning towards the southeast. At this time, the areas most likely to be affected by this MCS should be places west and SW of NYC, towards western New Jersey, however the MCS is still far to our west, and it may end up slightly north or south of the forecast. If needed, a brief update will be posted around 8 PM, followed by a full update by 10 PM.

Thursday, July 22, 2010

July 22: Storms, Heat Return This Weekend

Blog Updates: The 5-Day Forecast has been updated for the entire area. In addition, a summary of yesterday's severe weather event will likely be posted either tomorrow or Saturday.

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After yesterday's intense storms in the northern parts of the area, today proved to be a very nice day, with more sunshine and high temperatures in the 80s to lower 90s. Things are about to be turning more active, however, with the return of storms to the forecast, as well as heat that could rival that of the early July heat wave.

Tomorrow's Outlook:

Tomorrow will bring warmer temperatures to the area, however there is uncertainty on how much the temperatures warm up, which depends on a storm to our north. A low pressure is expected to stay to our north as the warm front moves through, however how far north is still uncertain. The GFS is farther south, and brings rain to the northern parts of the area, with chilly temperatures. The NAM keeps the rain well to our north, and as a result, brings much warmer temperatures. The other models are further north than the GFS with this storm, so at this time, I have followed the northern scenario for my forecast.

For now, I am expecting high temperatures to be in the upper 80s to lower 90s for northern NJ and NYC, with mid 90s possible southwest of NYC. Long Island and S CT, with an onshore wind, as well as being the farthest away from the warm front tomorrow afternoon, should only warm up to the lower to mid 80s. Mostly cloudy skies are expected, with isolated showers and thunderstorms possible in the evening into the overnight hours for the northern parts of the area. This forecast is not certain yet, and the temperatures could end up as much as 5-10 degrees cooler for northern NJ/NYC should the rain end up further south than currently expected.

Saturday And Sunday: Very Hot, Humid, Stormy

As the warm front moves through on Friday night, temperatures should stay mild, along with increasing humidity. Low temperatures will cool down into the lower to mid 70s inland, mid to occasionally upper 70s for southern CT and Long Island, and the upper 70s to lower 80s for the immediate NYC area.

With the warm front north of the area, and any scattered storm likely to stay to our north, Saturday will be one of the hottest days with the year, with the highest heat index of the year so far. High temperatures will rise into the mid 90s for the interior, lower to mid 90s for Long Island and S CT with a few upper 90s possible for western Long Island, and upper 90s to lower 100s for the immediate NYC area. Dew points are expected to be in the 70s, which would lead to the heat index reaching the mid to upper 100s for the immediate NYC area. The interior areas would see a heat index in the upper 90s. Partly cloudy skies are expected, however an isolated shower or thunderstorm is possible in the northern parts of the area.

Saturday night should be warm and humid, with low temperatures only dropping into the mid to upper 70s inland, and the upper 70s to lower 80s for the immediate NYC area. Combined with humidity, it will feel even warmer.

By Sunday, the cold front should approach the area, however there will still be enough time before it moves through for the immediate NYC area to warm up into the lower to potentially mid 90s, and the upper 80s to lower 90s for the interior areas. Scattered showers and thunderstorms are expected as the cold front moves through, temporarily ending the heat and humidity.

Early Next Week Outlook

Next week should start out slightly cooler with less humidity, with high temperatures in the mid to upper 80s for Monday with mostly sunny skies. Low temperatures will drop into the upper 50s to lower 60s inland and the upper 60s to lower 70s for the immediate NYC area for this time period. Tuesday should slightly warm up, with high temperatures in the upper 80s to lower 90s for the immediate NYC area.

Wednesday, July 21, 2010

July 21: Very Hot And Humid Saturday

Today proved to be a very active day for the northern parts of the area, as while the worst of the severe storms did not affect central New York like the forecast expected, the severe storms instead affected the corridor from south central NY through southeastern NY into Connecticut and Long Island. Interestingly, despite several severe storms moving through that area, none of these storms reached New York City, which has not seen rain today.

Today was not the only chance of strong to severe storms this week, however. There is also the potential of storms between Friday and Sunday, however these storms should be nowhere as strong as today's storms.

Tomorrow's Outlook:

Tomorrow should be another hot day, however it should not be as humid. High temperatures should be in the upper 80s to lower 90s across the area, and with a west wind, parts of Long Island and S CT should also reach the lower 90s.

Tomorrow is expected to be dry, as the cold front is well offshore, however tomorrow should be the only dry day this week. Friday already brings the return of storms and humidity.

Friday To Sunday: Very Hot, Humid And Stormy

Friday should still be relatively dry for parts of the area, however as a warm front approaches the area, the chance of storms returns for Friday for the northern parts of the area. The models are showing a large area of rain to our north during the evening, which means that most of the area is likely to stay dry, however some storms are possible in the northern parts of the area. Highs will reach the upper 80s to lower 90s with increasing humidity.

As the warm front lifts through the area, Friday night should not be chilly, as the lows drop into the mid to upper 70s for the immediate NYC area and lower to mid 70s inland. With the warm front and the storms north of the area on Saturday, highs should heat up into the mid to upper 90s, with a few 100 degree readings possible for the immediate NYC area. With dew points in the 70s, it will feel like the mid to potentially upper 100s, and most of the area should stay dry, despite an isolated storm or two possible north of NYC.

Saturday night again should not cool down very much, with lows in the upper 70s to lower 80s for the immediate NYC area. The cold front should move through on Sunday, bringing a risk of scattered thunderstorms. More details will come on this potential over the next few days. Highs should still be hot, in the lower to possibly mid 90s, with cooler temperatures for the start of next week.

July 21 Storm Updates

With enough sunshine, the area is currently heating up quickly, with temperatures already in the lower to mid 90s away from the coast, along with a few upper 90s near the immediate NYC area. The temperatures are still warming up, which is leading to increased instability.

Looking at the latest regional radar to the left, there is widespread activity in the Northeast, where the SPC has issued a moderate risk for severe weather today. While some thunderstorms are expected in the area, some which could reach severe levels, especially in the northern parts of the area (SE NY/NW NJ, southern Connecticut), the area should be nowhere as active as places to our north are, mainly due to less supportive parameters.

Below, I will post updates for the storms until 4 PM today. An update will be posted tonight, with more details on this weekend's storm potential, as well as the return of very hot and humid temperatures.

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8:09 PM: Strong to locally severe storms continue to affect the area. The first area of storms is currently in east central Long Island, and moving ESE. This area of storms is capable of producing strong wind gusts and hail. A second area of storms is in SE NY, entering SW Connecticut, and should affect the Stamford to Bridgeport corridor with heavy thunderstorms. A severe thunderstorm is reaching Stamford, CT, and is capable of producing large hail and damaging wind gusts as it intensifies.

Another strong storm is currently in central Orange county, and is moving ESE towards central Westchester county. For the longer range beyond the next hour, another round of storms is approaching western Orange County. Meanwhile, New York City continues to stay dry as the storms are staying just to the north. This is expected to continue, with the next several storms in line also staying just to the north of NYC.


6:38 PM: Another storm is currently entering Long Island, moving towards Sag Harbor, NY and the rest of eastern Long Island, tracking just south of the storm that just went through. This storm is not as intense as the previous storm, however it is also capable of producing damaging wind gusts and hail, as well as potentially localized flooding.

The other storm is currently affecting Stamford, CT. This storm is also severe, and may produce damaging wind gusts and large hail. Another round of storms is entering Orange County, however most of these storms have dropped below severe levels. Still, they are capable of producing strong wind gusts and small hail.


6:26 PM: WARNING: ***A Tornado Warning is in place for eastern Long Island, including Sag Harbor, NY***. This storm is also capable of producing damaging wind gusts, large hail and heavy rainfall.

Another severe storm is currently entering SW CT, and should affect places between Stamford and Norwalk, CT. This storm may also produce an isolated tornado should it intensify.


6:19 Special Update: The northern part of the area has become increasingly active over the last 2 hours, with a potential tornado having been observed in southwestern Connecticut. The current main area of concern is in northern Westchester county, out of a severe storm producing large hail and damaging wind gusts. This storm is moving SE, and should affect Stamford, CT within the next 30-45 minutes.

The storm that previously produced the potential SW CT tornado is now in the Long Island Sound, moving southeast. This storm is still severe, and is approaching Riverhead, NY. Damaging wind gusts and hail are expected with this storm, as well as the potential of an isolated tornado, as this storm has already produced a tornado warning previously.

There is a widespread area of strong to severe storms in southeastern CT, which are each capable of producing strong wind gusts and small hail. There is another severe storm in Somerset County, NJ moving SE, also capable of producing small hail and strong wind gusts. Another storm will enter parts of Hunterdon and Warren counties soon, with another round of storms about to move into Orange County.

Meanwhile, New York City continues to stay dry as the storms are to the north and south of the city. Unless an isolated shower or storm forms in between, NYC is likely to go through today staying dry.


3:04 PM: The storm approaching northwestern New Jersey has dropped below severe levels, and continues to weaken. Like most storms that approached the area, this one has also weakened, as the parameters for severe weather in the area are not as supportive as places further north. This could also be the case with the rest of today, as most of the activity and the supportive parameters are to our north, with only relatively weak and isolated activity south of the NY/PA line.

Meanwhile, a storm near Ossing, NY has intensified and is now capable of producing small hail and gusty winds as it moves to the east, towards southwestern Connecticut.


2:25 PM: Several storms are currently affecting the area. There is a severe thunderstorm in central Long Island moving northeast, capable of producing strong wind gusts and hail, as well as heavy rainfall. The second area of storms is in northern Rockland county, moving east, however this storm is below severe levels and is weakening, which should lead to moderate rain and thunder.

The next storm to affect the area is currently in northeastern Pennsylvania, moving east southeast towards far northwestern Sussex county and western Orange county. This storm should approach that area within the next 40-60 minutes. This storm is very dangerous, and is capable of producing large hail, damaging wind gusts, and is also producing a potential tornado.

Tuesday, July 20, 2010

July 20: Stormy Wednesday, Hot Saturday

Yesterday was the start of what will be an active week. There were scattered showers in the area today, with the threat of scattered strong to severe thunderstorms for tomorrow and Saturday. In addition to the storms, the heat and humidity is going to continue, with the heat index potentially near or over 100 degrees during several occasions.

Tomorrow's Outlook:

Tomorrow will be warmer than today, with high temperatures in the upper 80s to lower 90s, which combined with dew points in the 70s, would lead to the heat index reaching the mid 90s. There is also the possibility of scattered showers and thunderstorms, some of which could reach strong to severe levels. There is higher wind shear and lapse rates than in previous outbreaks, which would lead to higher severe weather chances, however the NAM and GFS significantly differ with tomorrow's potential. Both models, however, seem to indicate that the worst of the storms will be to our north.

As a result, I am expecting scattered showers and thunderstorms late tonight into tomorrow morning, some of which could be strong, but no severe storms are expected. Another round of storms, locally strong to severe, is possible tomorrow afternoon, but the highest risk of severe weather should be to the north of the area. If needed, updates will be posted between 2-4 PM tomorrow.

Thursday And Friday: Very Warm, Some Storms

Thursday will be slightly cooler and less humid, with highs in the mid to upper 80s expected. Thursday should be the only dry day, however. Friday will already bring a chance of storms as a warm front approaches the area, with highs in the upper 80s to lower 90s.

By Saturday, more uncertainty returns to the forecast. The models originally showed a strong cold front moving through on Saturday, however they have trended slower today, with the timing now expected to be on Sunday. This scenario would lead to Saturday being a very hot and humid day, with a scattered storm potential. High temperatures should be in the upper 90s to lower 100s away from the coast, and combined with dew points in the 70s, the heat index could reach the mid 100s for parts of the area. Sunday would also bring a chance of storms as the cold front moves through.

As I mentioned, there are differences with the potential solutions, and the timing could change. If the timing trends faster, then the front would move through on Saturday, and if the timing trends slower, then the storms would be mainly on Sunday, with Saturday not as hot with a slightly higher chance of storms. Stay tuned as more details become clear on this potential over the next few days.

Monday, July 19, 2010

July 19: More Storm Chances This Week

This afternoon was a very active day in parts of the area, most notably in northern Orange county, where storms dumped up to nearly 6 inches of rain according to radar estimates, and in northern Bergen county, where a severe thunderstorm brought strong wind gusts, heavy rainfall and hail.

This is only the start of what will likely be an active week. Not all places are likely to get rain, but there is a chance of storms almost every day for the next several days, with no relief from the heat.

Rest Of Week Outlook:

Some storms are possible tomorrow night, however there is still uncertainty, as the models significantly vary with the location and intensity of the heaviest rain. There is a potential MCS that may approach the area, and as mentioned above, the models show different solutions, some bringing it to the north of the area, others to the south, and some don't bring rain to the area. More details on this potential will come tomorrow. High temperatures should be in the upper 80s to lower 90s.

Wednesday should be drier, though an isolated shower or thunderstorm is still possible, with highs in the upper 80s to lower 90s. Thursday is expected to dry up, with temperatures slightly warming up.

Weekend Outlook: Hot, Humid And Potentially Stormy

For Friday, there is a storm potential as the next storm approaches the area. There is uncertainty with the timing of this event, as the models continue to have slight changes with each run, which can be expected at this range, however the overall set up does show a storm to our north sometime between Friday night and Saturday night, bringing a cold front through.

If the slower solution verifies, Saturday would be very hot and humid, with highs in the mid to upper 90s, with 100 degrees possible in the warmest case scenario, along with the potential of strong to severe thunderstorm. The latest models, however, have trended faster with the timing, which would already bring the storms through the area by the early afternoon, reducing both severe weather chances and the temperatures. Stay tuned for more details on this potential.

Afterwards, the models bring in a much colder air mass, with highs dropping into the lower 80s and low temperatures into the lower 60s. Looking at previous cold fronts this summer, however, the models also kept showing colder temperatures returning behind each cold front, and slowly backed off the cold as the event approached the shorter range. At this time, I am leaning towards the warmer scenario, where temperatures after the cold front stay warm, in the upper 80s to lower 90s, however this is still in the longer range and may change.

July 19 Afternoon Update

Yesterday, some models started showing the possibility of morning storms moving through the area today. This turned out to be reality, with a severe thunderstorm moving through northeastern NJ and southern Connecticut, producing heavy rainfall up to 1.5 inches and damaging wind gusts. This area of storms is still active, located near Cape Cod on the radar image posted to the left.

More storms are on the way for this afternoon, however. While the parameters for today's event are not very impressive, they are supportive enough for the threat of isolated to scattered strong to severe thunderstorms for parts of the area, with at least an overall 1o% to 15% risk. There are still more storms forming, with others intensifying, which some of them should reach the area starting 4-5 PM. Any storm that becomes strong or severe will be capable of producing heavy rainfall and gusty winds, with small hail a possibility. At this time, it appears that the highest risk of severe storms would stay in the northern parts of the area (SE NY, southern CT), along with parts of northern NJ and NYC, however this can still change.

For the short term, the storms should affect the northern and western parts of the area, with more storms expected through late tonight, also spreading into other parts of the area. Today's update will be posted later tonight, with an update on the next chances of thunderstorms, as well as the potential return of heat on Saturday.

Saturday, July 17, 2010

July 17: Another Hot Week Ahead

Note: The 5-Day Forecast was updated today for the immediate NYC area and the interior.

The hot temperatures that are in place show no sign of leaving, as another hot week is ahead of the area. Today reached the lower to mid 90s again, and while there will be some cooler days, especially for the middle of this week, the above average temperatures will persist.

Tomorrow's Outlook:

Tomorrow should continue with 90+ degrees away from the coast, however it should be slightly cooler than today, with lower to mid 90s for the immediate NYC area, and upper 80s to lower 90s for the interior. Long Island and southern CT should also warm up into the upper 80s.

The area should stay dry, with mostly sunny skies, however as with today, showers and thunderstorms, some of which could become severe, are expected to our west, in western Pennsylvania and New York.

Monday And Tuesday: Hot, Humid And Some Storms

As a cold front approaches for Monday, scattered showers and thunderstorms are expected. Due to the lack of supportive parameters, no widespread strong to severe thunderstorms are expected, and these storms also shouldn't produce heavy rainfall like the storms early this week. High temperatures should be in the lower to mid 90s, which combined with humid conditions, will make it feel like the upper 90s.

For Tuesday, a slightly cooler air mass moves in, but like the others so far this year, it should considerably weaken by the time that it reaches the area, with high temperatures in the upper 80s to lower 90s for the immediate NYC area, and the mid to upper 80s inland. The only significant change should be the lower humidity.

Longer Range: Heat Slowly Returns

Wednesday and Thursday should slowly warm up, with temperatures staying in the upper 80s to lower 90s for the immediate NYC area. By Friday, however, the next cold front should approach, with temperatures likely returning into the lower to mid 90s, along with higher humidity. There is still some uncertainty, as not all of the models are consistent with this solution, however it would bring a chance of storms for Friday and Friday night. More details on this potential will come once there is less uncertainty.

Afterwards, there are large differences with the models. Some bring in a large trough, with temperatures cooling down into the upper 70s to lower 80s. Looking at this summer's pattern, however, such a solution would be unlikely, as most of the cold air masses that approached the area significantly weakened once they reached the area. As a result, no significant change is expected with the temperatures, with highs potentially staying in the upper 80s to lower 90s.

Friday, July 16, 2010

July 16: No Relief From Heat

For parts of the area, today was the hottest day since the early July heat wave, with the immediate NYC area reaching the mid to upper 90s. In fact, Newark, NJ reached 99 degrees today. Unfortunately, there is little or no relief from the heat, as other than a brief cool down in the middle of next week, with temperatures returning into the upper 80s, 90s should persist into the longer range.

Tomorrow's Outlook:

Tomorrow should be about as hot as today, but with less humidity. With a WSW wind, high temperatures will reach the lower to mid 90s for the interior, mid to upper 90s for the immediate NYC area, and the upper 80s to lower 90s for Long Island and S CT. Due to dew points in the upper 50s to lower 60s, it should not be as humid as today was.

The area should stay dry for tomorrow, however it will not be as dry to our north and west, as there is a risk of thunderstorms tomorrow for western NY and PA. Some of these storms could reach strong to severe levels, though they are not expected to reach the area.

Sunday And Monday: Heat Wave Continues

The heat wave should continue through Monday. Sunday will not be as hot as the previous days, with high temperatures in the lower to mid 90s away from the coast, though Monday should be simiar to today, with high temperatures back into the mid to upper 90s for the immediate NYC area. It should also be more humid on Monday, with dew points in the upper 60s to lower 70s, leading to the heat index reaching the 100s again.

There is the potential for a few isolated storms on Monday. While a cold front should move through, it should already be weak when it reaches the area, with very little change in the air mass behind it. With relatively unsupportive severe weather parameters, scattered non-severe thunderstorms are possible for Monday, however they are not expected to bring heavy rain amounts like the storms earlier this week.

Longer Range: Heat, Dry Conditions Persist

Tuesday should be slightly cooler after the cold front passes with less humidity, with temperatures cooling down into the upper 80s to lower 90s. By Wednesday, however, temperatures already warm up again, reaching the lower to occasionally mid 90s away from the coast. This hot pattern is expected to sustain itself, and while there will be some cooler days, this current hot and dry pattern is expected to last into the longer range.

Brief July 16 Afternoon Update

Brief update for the short term weather:

Today is already starting out hot, with temperatures in the lower to mid 90s away from the coast and some upper 90s southwest of NYC, which combined with dew points in the 70s, is leading to the heat index reaching the lower 100s.

The front is moving through faster than Wednesday's forecast expected, which would keep the area dry tomorrow, however today the severe weather potential for the region extends from eastern NY to Vermont, New Hampshire, western Massachusetts, and parts of western Maine and central PA, where there is a 10% risk of severe weather. There are currently isolated strong to severe storms, however a widespread severe outbreak is not expected for these places today.

Forecast For NYC Area: Parts of the area are probably going to stay dry for today, however there is an area of storms in central Pennsylvania, moving towards the area. If these storms reach the area, they should likely bring thunderstorms, which should bring heavy rain, with a few storms reaching strong levels, producing isolated hail and moderate/strong wind gusts. It is possible that these storms weaken as they reach the area, so it is still uncertain whether they affect the area or not. More details may be posted later this afternoon.

This will be the start of a four day heat wave, however. With a warm air mass remaining in place, tomorrow will be just as hot as today, if not even hotter, with high temperatures in the lower to mid 90s with a few upper 90s away from the coast. It should be slightly less humid than today, though. Sunday and Monday will continue with these hot conditions, with highs in the lower to mid 90s, with a few upper 90s possible near or SW of NYC, with more humid conditions returning for Monday.

The next potential for showers and thunderstorms returns for Monday and Tuesday. More details on this storm potential, as well as the longer range, will be included in tonight's post.

Wednesday, July 14, 2010

July 14: Heat Returns And Persists

Today was another wet day for the area, with another 1 to 2 inches of rain across parts of the NYC area. Fortunately for those areas that received flooding, there should not be widespread rain until at least Saturday, however the heat and humidity are going to return, and like most of this summer so far, should continue to persist into the longer range despite several cold fronts moving through.

Tomorrow's Outlook:

Tomorrow will be warmer and drier than today. With mostly to partly sunny skies, temperatures are going to be able to warm up more, but an east wind will limit how much temperatures warm up. High temperatures should reach the upper 80s to lower 90s inland, with the lower to mid 80s for Long Island and southern Connecticut. The rest of the region should also be dry.

Friday - Monday: Hot, Humid And Some Storms

Friday should be the first of several hot days, with high temperatures reaching the mid to upper 90s away from the coast. With dew points in the 70s, this would lead to the heat index reaching the lower 100s. An isolated shower or thunderstorm is possible for the western parts of the area, however most of the storms should stay in western Pennsylvania and New York, where some of these storms could reach strong to severe levels.

By Saturday, the cold front should reach our area, however like the other cold fronts this summer, it will fail to bring any relief from the heat. Scattered showers and thunderstorms are expected, with some storms producing heavy rainfall, however there is only an isolated severe weather potential due to slightly better parameters than today, but still not very supportive, as well as unsupportive cold front timing. For locations that will not be affected by the rain, the heat will persist, with temperatures reaching the upper 80s to lower 90s.

Sunday and Monday should not be as humid, but hot temperatures will continue, reaching the lower to mid 90s. Monday should be the hottest out of both days, with isolated locations south and SW of the immediate NYC area potentially reaching the upper 90s. Humidity should be much lower for Sunday, slightly increasing for Monday.

Next Storm Potential: Monday Night And Tuesday

The next storm potential is expected for Monday night and Tuesday. Another cold front should approach the area, bringing another potential of scattered showers and thunderstorms. Severe weather potential, if any, is uncertain at this time, however these storms could also bring heavy rain.

Behind this area of storms, once again, little or no relief is expected from the heat. As with previous cold fronts, humidity should decrease, however the hot temperatures should persist once again, staying in the 80s and 90s.

Tuesday, July 13, 2010

July 13: Humidity And Rain Continue, Heat To Return

As expected, the area mainly stayed dry from 5 PM until now, however there is much more rain to come tonight, especially for the southern and eastern parts of the area. The rain continues until tomorrow, when it should be dry again, however there should be no relief for both the short term and long term, as heat and humidity should make a return later this week.

Tonight's Outlook:

The heavy rain currently in Maryland and Pennsylvania should continue to move ENE, however it is uncertain how it affects the area. The main band of rain split, with the southern and western ends intensifying, and the middle part, apparently moving towards the NYC area or west of NYC, weakening into light rain.

There should be more rain behind that area, however, as the area of rain in south central PA should affect our area later tonight, bringing widespread moderate to heavy rain. The majority of the rain should fall in the southern and eastern parts of the area, where another 1 to 2 inches of rain are possible, with amounts between 1/2 and 1 inch for the rest of the area, locally reaching 1-2 inches.

Tomorrow's Outlook:

Tomorrow will be another rainy day across the area, especially in the morning. By the late afternoon, the storm should mainly move out, bringing lighter rainfall, but any showers will still be capable of producing heavy rainfall. High temperatures should be slightly warmer than today, reaching the lower to mid 80s with a few upper 80s.

Late Week: Heat, Humidity Return

As mentioned yesterday, hot and humid conditions should return by late this week. As there should be temporarily drier conditions (though an isolated shower or storm can't be ruled out on Friday), temperatures should rise into the lower to mid 90s on Thursday, and the mid to upper 90s on Friday away from the coast, which combined with dew points in the lower to mid 70s, should lead to the heat index reaching the 100s.

Next Weekend And Beyond: More Storms, But Heat Continues

The next cold front should affect the area on Saturday. This front should bring a risk of severe weather for western New York and Pennsylvania for Friday, however this risk should be smaller by the time that it gets here. The wind shear and lapse rates are more supportive than they were for today, however they are not too supportive, leading to at least a 5-10% risk of severe storms. The main threat with these storms again should be heavy rainfall. Stay tuned for more details on this next rain potential.

The storms move out by Sunday, however the cold front, like most cold fronts so far this summer, will fail to bring much relief from the heat. There should be less humidity, however the temperatures will stay just as hot, in the upper 80s to lower 90s, and may warm up for early next week.

July 13, 2010 Storm Updates

An area of heavy storms moved through the area in the last 1-2 hours, which dumped heavy rain up to 1-2 inches for the immediate NYC area. These storms were only the start of what is likely to be a wet day for the area, with more rain likely tonight and tomorrow. Rainfall totals are expected to end up between 1 and 3 inches for parts of the area, with locally higher amounts.

The observations for today's storms are going to be posted below, including short term forecasts.

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5:00 PM: The heavy rain coverage has ended for now. There is still heavy rain affecting Long Island and Connecticut, which should continue to do so for at least the next hour or two. Other than an isolated storm or two, northern NJ and SE NY are dry.

Looking at the regional radar, however, there is an area of heavy rain in West Virginia and SW PA, moving ENE. This should mainly stay to our south, however it could bring some heavy rain, especially to the southern and eastern parts of the area. More details on this area of rain will come with an update tonight.


4:24 PM: Heavy rain is currently moving through the rest of southern Connecticut, bringing rainfall amounts between 1/4 and 1/2 inch. The heaviest rain is located in western CT, which moved through SW CT and Brooklyn earlier, bringing 1-2 inches of rain. This cell is moving NNE.

Another round of heavy rain just moved into eastern Long Island, bringing very heavy rainfall. Additional 1-2 inches of rain are expected with this round.


3:22 PM: Looking at the latest radar, there are several areas of concern. The first is with the main band of rain currently moving through eastern Long Island, with lighter rain approaching south central CT, including Bridgeport and New Haven. This band is producing very heavy rainfall for eastern Long Island, with up to an inch possible in just 1/2 hour. A total of 1-2 inches of rain is likely there from this band.

Lighter rain is currently falling in southwestern and south central CT, with amounts up to 1/2 to 1 inch expected, though heavier rain may move into southeastern CT later this afternoon with the band in Long Island.

Light to moderate rain is also moving into NYC and NE NJ, with generally light rainfall amounts. Another area of storms is nearly stationary in central Morris county, NJ, which is slowly shifting north towards eastern Sussex and western Passaic counties.

Monday, July 12, 2010

July 12: Heat And Humidity To Return

Heavy showers and thunderstorms affected the western parts of the area earlier this evening, but like Saturday's storms, they dissipated before they reached the eastern parts of the area, including parts of NE NJ and NYC. There is more hope for rain tomorrow, which is discussed below, though afterwards dry conditions are likely to return to the immediate NYC area.

Tomorrow's Outlook:

Due to the cloud cover and rain tomorrow, temperatures should be colder than today, reaching only the lower to mid 80s, though with higher dew points in the lower to mid 70s, it should be much more humid, feeling like the upper 80s. A SSE wind is expected for tomorrow.

Meanwhile, the potential for heavy rain returns for the immediate NYC area, but considering how the last few rain potentials have gone, whether NYC gets the heavy rain tomorrow or not is a question. There is still uncertainty on the axis of the heaviest rain, as a low pressure should form around the area that would enhance the rain, but it is uncertain where the low pressure develops.

If it happens near or slightly west of NYC, the result would be heavy rainfall for northern NJ, NYC, Long Island and S CT, reaching 1 to 2 inches with locally higher amounts. If this happens to the east of NYC, however, the heaviest rain would stay in Long Island and southern CT, with lighter rain for NYC and northern New Jersey. At this time, most of the models are showing the low pressure east of NYC, except for the NAM which has it further inland. For this forecast, I am following the second scenario where the low pressure is east of NYC, with rain for Long Island and S CT between 1 and 2 inches, the immediate NYC area reaching 1/2 to locally 1 inch, with NW NJ seeing 1/4 to 1/2 inch with locally higher amounts.

Thursday And Friday: Hot, Very Humid

Thursday and Friday are likely to be dry, as a high pressure temporarily returns to the area with the next storm being well to the west. Meanwhile, with the humidity in place, a much warmer air mass will return to the area, leading to high temperatures significantly warming up. Thursday should reach the lower to mid 90s away from the coast, and with dew points in the upper 60s to lower 70s, it will feel like the upper 90s.

Friday should be even hotter, with 850 mb temperatures nearing 20c. This, combined with mainly to partly sunny skies, will lead to high temperatures in the mid to upper 90s. Along with dew points in the upper 60s to lower 70s, it will feel like the lower 100s.

Next Weekend: Storm Potential Returns

By next weekend, however, the next storm approaches, bringing colder temperatures and the potential for more rain. On Friday, the cold front should affect places to our west, in the Great Lakes region, and the front should affect the area on Saturday. This time, there may be a slightly higher chance of severe weather, with some wind shear in place. At this time, a widespread severe weather outbreak is not expected, however there is still time for things to change, so that potential will be kept an eye on.

After this round of storms, temperatures should remain warm. As the warm air mass persists, high temperatures should remain very warm, in the 80s and 90s.

Sunday, July 11, 2010

July 11: Warm, Humid And Stormy Week Ahead

Today brought nicer conditions than yesterday, with more sunshine and warmer temperatures, though there were isolated yet heavy thunderstorms across parts of the area, most notably for eastern New Jersey, with an isolated area in eastern Bergen County seeing nearly 3 inches of rain. Tomorrow should bring drier conditions to the whole area, but enjoy it while it lasts, as tomorrow should be the last dry and mainly sunny day for a while.

Tomorrow's Outlook:

Tomorrow should be mainly sunny and dry for the area. With slightly warmer 850 mb temperatures, and more sunshine than today, high temperatures will rise into the upper 80s to lower 90s away from the coast, and I wouldn't be surprised to see a few mid 90s for the immediate NYC area. With a south wind, Long Island and S CT should rise into the mid to upper 80s, with the immediate coast in the upper 70s.

The area should be dry tomorrow, though the dry conditions won't last for long. Storms will slowly approach from the west tomorrow, affecting the southern and western parts of the Mid Atlantic. These storms should reach the area by Tuesday. Humidity should start to increase through Monday night.

Warm, Humid And Stormy Pattern Starts Tuesday

Starting on Tuesday, with a humid air mass in place, full of moisture, scattered showers and thunderstorms are expected. These storms should not be severe, but should be capable of producing heavy rainfall. There should be a few minor changes in the pattern, such as different front and low pressure locations, including Tuesday night to Wednesday being a more likely time frame for rain, but the theme of scattered storms each day with warm and humid conditions will continue through the week into next weekend.

High temperatures are expected to be in the mid-upper 80s, with a few lower 90s for places that get enough sunshine, and with dew points in the 70s, it should feel much warmer, with the heat index in the lower to mid 90s.

The storms are expected to continue through next weekend at this time, however there is still uncertainty on when the stormy pattern ends, whether it's during the early weekend or early next week. Stay tuned for more details on this stormy pattern, how much rain it may bring and when it could end.

Saturday, July 10, 2010

July 10: Dry Conditions Persist For Now

Today's bust for New York City was one of the biggest busts of the year. The set up suggested a heavy rain scenario, which did verify for western New Jersey and Orange County, NY, as well as Long Island and S CT which got heavy rain from scattered yet heavy thunderstorms, however the storm line collapsed at the last minute, preventing NE NJ and NYC from seeing any rain today. In fact, looking at a larger picture of the region, other than eastern Maine and SE CT, the immediate NYC area was the only area not to get rain out of the entire Mid Atlantic and Northeast.

This storm was expected to help end the dry conditions, which is what happened for Long Island and NW NJ. Northwestern NJ ended up with significant rainfall today, with a few places reaching 3-5 inches. In fact, the Allentown, PA area had their fourth wettest day on record, with rainfall over 5 inches. For NYC, however, the dry conditions are expected to persist for now, with the next hope of ending the dry conditions coming next week. More details on that potential have been posted below.

Tomorrow's Outlook:

Tomorrow should be drier for those places that got rain today, and fortunately, should also be less humid. With NW winds, high temperatures should rise into the upper 80s for northern NJ with a few lower 90s possible for the immediate NYC area, though Long Island and S CT should stay cooler, with high temperatures in the upper 70s to lower 80s.

The storm will still have lingering showers and thunderstorms across the area tomorrow, however with lower humidity, these storms should not be similar to those of the last 3 days, which were able to produce heavy rainfall. The areas more likely to see isolated showers should be north and east of NYC.

Next Week: Hot, Humid And Stormy

Monday is likely to be the only day of the week with no rain expected for the area. With a south wind and warmer 850 mb temperatures returning into the area, high temperatures should reach the upper 80s to lower 90s for northern NJ. The dew points should start to slowly increase, reaching the mid 60s.

Starting Tuesday, however, the pattern should change. A more humid air mass should enter the area, leading to a warm, humid and stormy pattern. The dew points should increase to the lower to mid 70s, which combined with temperatures in the upper 80s with a few lower 90s away from the coast, would lead to uncomfortable conditions. At the same time, the precipitable water values should be over 2 inches, and with more moisture, this should lead to a threat of scattered showers and thunderstorms each day between Tuesday and Saturday.

As this should be a more prolonged potential of rain than today's storm, most of the area is likely to see rain at least some time next week. These storms will be capable of producing heavy rainfall, however severe thunderstorms are not expected due to the lack of supportive parameters.

The potential stated above is based on the majority of the models at this time. The NAM is different, however, and if it verifies, the rain potential would only be brief, with NYC staying mainly dry again, and dry conditions would already return by Thursday, though its latest run is wetter for NYC. The previous NAM solutions are unlikely at this time considering that they go against the rest of the models, however it is something to keep an eye on. Stay tuned for more details for next week's rain potential.

July 10, 2010 Storm Updates

10:59 AM: There is no longer a heavy rain threat for northern NJ and NYC today. The storm line continues to rapidly weaken, and is now nothing more than light to moderate rain. The National Weather Service has cancelled the flood advisories for the area, expect for eastern Long Island, however that is due to isolated heavy thunderstorm activity related to the humid air mass. These isolated storms should reach SE Connecticut later this morning.

Some rain is still likely for NE NJ, NYC and Long Island today, with rainfall amounts up to 1/4 or 1/2 inch possible with locally higher amounts, as some more rain is possible later this afternoon, however the heavy rain threat that was originally expected for today is very unlikely to happen.


10:22 AM: The storms continue to slowly move east around central NJ and for NW Connecticut, however the line is collapsing around northern New Jersey. Its eastern end has been stationary around far western Bergen County for the past hour, and with the western end slowly moving east, already over northwestern New Jersey, the rain is quickly weakening over northern New Jersey.

This only recently began to happen and it is uncertain if it changes the forecast or not, however should this band of rain continue to weaken, NE New Jersey and NYC may end up with significantly lower rain amounts than what was originally expected. More details will come later this hour.


9:25 AM: The line of storms is currently affecting northwestern NJ and southeastern NY, and for the next 1-2 hours, is approaching northeastern NJ, SW CT, and NYC. These storms are moving to the east very slowly, leading to flooding in some places, with radar estimates showing up to 3 inches in western NJ.

These storms are producing very heavy rain, and are capable of producing up to 1 inch in just 1/2 hour. Rainfall amounts should generally end up between 1 and 2 inches, with amounts locally reaching 3 inches.

Friday, July 9, 2010

July 9: Rain To Fall Tomorrow, Wednesday

Today was another warm and humid day, with a few isolated storms currently active west of NYC. These storms, as with yesterday, are isolated, but are producing heavy rainfall, with radar estimates showing a few rainfall amounts up to 1.5 to 2 inches of rain in western New Jersey. Tomorrow should bring much more widespread rain, however, with the entire area likely to see rain, which could be heavy.

Tomorrow's Outlook:

Tomorrow should bring heavy rainfall to most of the area. As the cold front slowly moves through the area, entering a humid air mass full of moisture, including high precipitable water, slow moving storms will form tomorrow, similar to those currently affecting western and central NY/PA, producing heavy rainfall in parts of the area, with amounts locally reaching 2 to 3 inches. Not everyone will see these rain amounts, as these heavy storms will affect parts of, but not the whole area, with most places likely to end up between 0.5 and 1.5 inch of rain.

As these storms will be slow moving while being able to produce heavy rainfall, they will be able to produce flash flooding, which is the main threat with tomorrow's storms. Due to the lack of supportive severe weather parameters, severe weather is not expected. High temperatures, meanwhile, will be much colder than today, due to the cloud cover and rain, in the upper 70s to lower 80s across the area.

Sunday And Next Week: Warming Up, Some Storms

As soon as the storm exits on Sunday, temperatures will start warming up. A few showers are still possible early, though high temperatures will rise into the upper 80s, with more sunshine and less humidity. Monday will continue warming up, reaching the lower 90s.

By Tuesday and Wednesday, the next storm should approach the area, bringing the risk of thunderstorms. The parameters are not very supportive of severe weather at this time, and while there is time for things to change, widespread severe weather is not very likely around this time frame. This should bring more scattered showers and thunderstorms to the area, which should help bring the monthly rainfall closer to average.

Afterwards, there are signs that temperatures may warm up into the lower to mid 90s once again as warmer 850 mb temperatures return. This is still uncertain as it's in the longer range, however temperatures are likely to warm up beyond the middle of next week, with drier conditions returning. Stay tuned for more updates on the longer range.