Saturday, June 30, 2012

June 29, 2012: Heat Continues Tomorrow


Forecast Highlights:


- Another day of 95+ degree heat tomorrow
- Storms to mostly stay south of NYC, some perhaps reaching NYC
- 4th of July warmer than average; possible storms?
- Another heat surge possible late next week


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Records tied/set today:


LaGuardia, NY
98 degrees (tied record: 98 degrees - 1959)

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Today's Observations:


As a blast of heat moved into the region, hot temperatures returned to the area today, matching those of last week in some places. The day started out with heavy thunderstorms to the north of a stronger line of storms that moved through Philadelphia, with cloud cover quickly clearing by the late morning with temperatures rapidly rising into the 80s and 90s.

Throughout the afternoon and evening, a large complex of severe thunderstorms moved through the Ohio Valley and into Virginia and Maryland, causing widespread severe wind damage. These storms will remain to the south of the area tonight, but will keep mostly cloudy skies in place. The pattern consisting of MCS moving through the region will continue on Saturday and Sunday, with most of the severe storms again staying to the south of NYC. Temperatures will slightly cool down on Monday and Tuesday, although are likely to slightly warm up again for mid-late next week with the potential for additional thunderstorms.


Weekend Outlook:


Hot temperatures will continue for the weekend, making this the 2nd heat wave of the month. Mostly sunny skies are expected for Saturday with temperatures reaching the mid 90s inland, mid to upper 90s in the immediate NYC area, and the upper 80s to lower 90s in Long Island/S CT, approaching the mid 90s closer to NYC and the mid 80s closer to the coast, especially further east. Slightly cooler temperatures are expected for Sunday with lower to mid 90s from NYC and further north/west, with mid 80s to lower 90s in Long Island/S CT.

With the pattern currently in place, the potential is also there for 1 or more MCS to move through the region on Saturday and Sunday. Given recent trends, the central Mid Atlantic is the most favored area to see additional severe storm activity during the weekend, although some storm activity cannot be ruled out in the area, especially towards the evening and overnight hours and further south/SW of NYC.


Next Week: Slightly Cooler, Still Warm For July 4th


With the core of the heat retreating back south/west, cooler temperatures are expected for Monday and Tuesday, although no significant cool down is anywhere in sight through the foreseeable future for the US. Temperatures will cool back down into the mid to upper 80s for most of the area, possibly a bit cooler further east closer to the coast, with mostly to partly sunny skies expected.

By Wednesday, the 4th of July, the models are showing the potential for a brief heat surge ahead of another cold front as the ridge remains stuck over the central US. With a warm front likely to move through earlier in the day as well, a warmer air mass will move in, although additional cloud cover may keep temperatures in the mid to upper 80s range. It is not out of the question that temperatures end up a bit higher than currently expected. There's still some uncertainty with the exact scenario and the precipitation outlook for Wednesday isn't high at this time, although the set up does support potential thunderstorm activity across parts of the region on Wednesday, possibly including the area. By late next week, temperatures are likely to stay in the 80s, generally above the 85 degree mark, although there is the potential for another surge of heat by next Friday or the weekend, which according to latest indications may bring another round of 90+ degree heat. Stay tuned for more information on the 4th of July outlook.

Friday, June 29, 2012

June 29, 2012 Morning Update


5:50 AM: Morning Storms, Afternoon Heat


When last night's update was made, a small severe thunderstorm popped up near western PA. Throughout the overnight hours, this storm intensified and became more widespread, moving into SE Pennsylvania while producing strong to severe thunderstorms. While this area of storms was approaching SE PA and southern NJ, a small area of heavy thunderstorms popped up to its northeast, near SE NY/NE NJ, and moved SE through New York City. These storms are below severe levels, although they are still capable of producing frequent lightning and heavy rain.

The morning storm development doesn't change the heat outlook for this afternoon; if anything, it could be a bit hotter than previously thought, with cloudy skies becoming mainly sunny later this morning and highs peaking in the mid to upper 90s inland, upper 90s in the immediate NYC area with low 100s in some areas west/SW of NYC and mid 90s closer to the coast, and upper 80s to lower 90s for most of Long Island/S CT, slightly cooler closer to the coast and hotter closer to NYC. Additional storms, possibly strong/severe, are possible in parts of the region for Saturday and Sunday in the evening/night hours, especially on Saturday night when some models indicate the potential for an MCS to move through, before temperatures cool back down into the 80s for highs by Monday.

Thursday, June 28, 2012

June 28, 2012: Peak of Heat Wave Friday, Saturday


Forecast Highlights:

- Heat to peak tomorrow, Saturday; upper 90s west of NYC
- Slow cool down into next week but no major cool down expected
- Storm potential becoming less likely

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Today's Observations:

As the heat blast in the central US continued to spread east, warmer temperatures reached the NYC area as well, with highs reaching the upper 80s inland, upper 80s to lower 90s in the immediate NYC area, and the lower to mid 80s in Long Island/S CT. The forecast verified for the western half of the area but was a bit too warm for Long Island/S CT.

With NE NJ and LaGuardia reaching 90-92 degrees, today marked the first day of the heat wave in these areas, as even hotter temperatures are expected for tomorrow and Saturday, getting as high as the upper 90s west and SW of NYC. The weekend storm potential, however, is becoming less likely, with dry conditions likely for most of, if not the entire time period from Friday through Monday. The heat will gradually weaken going into next week, with temperatures dropping back into the mid-upper 80s range, but no significant cool spell is on the way.


Tomorrow's Outlook:


The warmest 850mb temperatures will move through the region tomorrow, getting up to 21-23C, with partly cloudy skies becoming mostly sunny along with west/WNW winds for most of the area except for eastern parts of Long Island/SE CT. With these conditions in place, tomorrow will challenge June 21 for the hottest day of the year so far. Temperatures will quickly rise in the morning and early afternoon hours, reaching the mid 90s inland, mid to upper 90s in the immediate NYC area, and the upper 80s to lower 90s for most of Long Island/S CT, getting into the mid 90s closer to NYC and the mid 80s further east.

Yesterday it had appeared that there could be thunderstorms tonight, although this became less likely throughout the day, as severe storm development failed to take place further west as modeled 2-3 days ago.There is still the potential for an isolated thunderstorm late tonight into Friday morning, but widespread storm activity is not expected.


Saturday - Next Week: Slow Cool Down, But Still Very Warm


Although the core of the heat will continue to move SE towards the southeastern US, there is no strong cool air mass approaching the region, preventing the heat from quickly collapsing, with a gradual cool down expected instead. Saturday will still be hot, with temperatures in the mid to locally upper 90s from NYC and further west/SW and the upper 80s to lower 90s across the rest of the area, with coastal locations ending up a bit cooler. The latest NAM runs are showing a strong MCS moving through overnight with heavy rain and strong thunderstorms; although the potential is there for storms on Saturday and Sunday in the afternoon/evening hours, it is questionable if any widespread strong thunderstorm development can take place. Temperatures will continue to slightly cool down on Sunday, reaching the lower to mid 90s from NYC and further west, possibly a bit above 95 west/SW of NYC, and the mid 80s to lower 90s in Long Island/S CT.

There is some uncertainty regarding how much cool air comes in by next week. The GFS model is more bullish, showing highs in the 80s, while the ECM still keeps the area close to the northern edge of the heat, with temperatures in the upper 80s to lower 90s away from coastal areas lasting into the middle of next week. At this time, I am siding closer to the ECM but not as warm, with temperatures dropping into the mid to upper 80s range for the immediate NYC area on Monday/Tuesday, possibly warming up a bit across the area around the 4th of July. The models continue to differ with precipitation potential for next week; even though next week does not appear to be very wet, the possibility of some storms cannot be ruled out, although there is not enough confidence at this time to determine exactly which day(s) have a risk of storms. Stay tuned for more information on the outlook for next week, including the 4th of July outlook.

June 27, 2012: Heat Wave Starts Tomorrow


Forecast Highlights:


- Major heat wave covering large parts of US to extend into NYC
- 90+ degrees return Thursday-Sunday
- Storms possible Friday morning


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Today's Observations:


With the upper level low drifting away from the region, mostly sunny skies were observed today with temperatures warming back up closer to average, with highs reaching the lower 80s across most of the area with mid 80s in the immediate NYC area. Not surprisingly, Central Park had the lowest temperature in NYC with a high of 81, with Newark the hot spot with a high of 86.

A massive heat surge which has produced widespread 100 degree heat, even reaching the 110s in Kansas, will spread east to cover almost the entire central and southern US, with the area near the northern edge of the heat. As a result, 3 or 4 days of 90+ degrees are expected especially away from the coast, with temperatures possibly reaching the upper 90s again away from the coast.


Friday - Monday: Heat Wave Expected; Some Storms Possible


The warm up will continue through Thursday as well, with most of the area reaching the upper 80s to lower 90s for highs, getting close to 95 degrees in parts of the immediate NYC area. Mostly sunny skies are expected again with lighter WSW winds.

By Friday, the warmest 850mb temperatures will move through, reaching the 20-22C range. The models have been consistent with a shortwave moving through on Friday morning, although how much convection forms is still uncertain. For now, I am mentioning a risk of scattered thunderstorms for late Thursday night into Friday morning. The rest of Friday is likely to be dry with partly sunny skies and hot temperatures. There is still some slight uncertainty with how hot temperatures get, although I am siding with a NAM/ECM blend, leaning a bit below the NAM, with highs in the mid 90s inland, mid to upper 90s in the immediate NYC area, and the upper 80s to mid 90s in Long Island/S CT away from the immediate coast.

Saturday and Sunday are expected to be hot as well especially west and southwest of NYC, but likely not as hot as Friday as the warmest temperatures aloft slowly shift further south. Mid 90s are still expected further west, with mid 80s to lower 90s in Long Island and southern CT. There is a slight potential for isolated storms, although it is increasingly likely that most of, if not the entire weekend may end up dry. Temperatures will gradually cool back down into the 80s next week, although no significant cool spell appears to be on the way.

Wednesday, June 27, 2012

June 26, 2012: Blast of Heat Coming Up


Forecast Highlights:


- Temperatures to gradually warm up this week
- Heat surge moves in Thursday to Monday; heat wave possible
- Storm potential for parts of area this weekend


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Today's Observations:


With an upper level low in place over the region, widespread cloud cover was observed with partly to mostly cloudy skies. The ULL in place also brought temperatures colder than average across the area, only peaking in the lower to mid 70s across the area when average temperatures during this time of the year are in the lower to mid 80s. Central Park observed a high of 72 degrees, which once again makes it the coldest temperature in NYC, a trend that has been observed since the previous heat wave.

The upper level won't last for long, however. A strong ridge with 110 degree heat in the central United States will extend east to cover most of the central and southern US, with the northern Mid Atlantic region including NYC in the northern boundary of this massive blast of heat. With the area near the boundary, the Friday through Monday time frame has the makings of a potentially active pattern, with heat and humidity away from coastal areas with a risk of thunderstorms.


Tomorrow's Outlook:


The ULL will begin to move out with temperatures moderating closer to average. Mostly sunny skies are expected across the area tomorrow with highs reaching the upper 70s to lower 80s for most of the area. Parts of the immediate NYC area will reach 85 degrees. Breezy NW winds are expected again.


Thursday - Early Next Week: Blast Of Heat; Storm Potential


As previously mentioned, a massive blast of heat will move into the central and southern US, resulting in widespread 100+ degree heat, getting as far north as the Ohio Valley and the southern Mid Atlantic. The northern Mid Atlantic will be near the northern gradient of the heat, which makes for an interesting pattern with both heat and thunderstorm potential. Despite 850mb temperatures near 20C supporting heat, the question of the wind direction, especially further east, and the amount of storms/cloud cover comes up, which limits just how hot temperatures will get.

Thursday will still have mostly sunny skies with temperatures reaching the upper 80s to lower 90s across most of the area, approaching 95 degrees in parts of the immediate NYC area but likely staying below the 95 degree mark. Southern CT and coastal parts of Long Island will be slightly cooler, with highs in the mid to upper 80s, possibly reaching and/or slightly passing 90 degrees. By Friday, the heat gradient sets up near the area, sticking around through Sunday. If there is enough sunshine especially through the afternoon hours, temperatures away from the coast are capable of warming up well into the 90s, with cooler temperatures near the coastal areas, likely in the 80s and possibly the 90s if winds end up more from the west than the south. The thunderstorm potential is uncertain, although there is a risk of thunderstorms each day between Friday and Sunday, with the potential for severe thunderstorms also present. This risk, however, does not mean that it will rain across most of the area each day, but rather that a potential exists for rain each day. By early-mid next week, a weak trough will likely move into the region, with highs cooling back down into the 80s. Stay tuned for more information on the heat and storm outlook for the weekend.

Monday, June 25, 2012

June 25, 2012: Chilly Temperatures Briefly Return


Forecast Highlights:


- Chilly Tuesday; gradual warm up through Friday
- Brief surge of heat possible on Friday and/or weekend
- Additional storm chances for the weekend


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Today's Observations:


A cold front moved through the region today, following the last cold front on Friday which resulted in severe thunderstorms in parts of the area. Today's cold front didn't result in widespread severe weather similar to that of Friday, but widespread storms were still observed with two rounds; in the late overnight to early morning hours, heavy rain/thunderstorms with some hail and gusty wind reports moved through the area, focusing over SE NY, NYC and Long Island, where amounts locally up to 2 inches were observed. Several hours of dry weather were observed afterwards, followed by the cold front moving through in the afternoon, resulting in a line of strong thunderstorms moving through SE NY, parts of NE NJ, NYC, and parts of Long Island/SW CT in the afternoon hours, once again bringing heavy rain and some hail. The afternoon line was followed by additional scattered storm activity. Temperatures were noticeably cooler than those of yesterday, only reaching the mid to upper 70s from NYC and further north/west and the lower to mid 70s in Long Island/S CT.


Tomorrow's Outlook:


A chilly air mass has moved into the region behind the cold front, and will stay in place through tomorrow while a coastal low pressure develops off the New England coast and retrogrades into Maine. Partly cloudy skies are expected with a risk of isolated showers in the afternoon, especially north/NE of the city, with highs reaching the lower to mid 70s inland and the mid 70s across the rest of the area, getting close to the upper 70s in the immediate NYC area.


Wednesday - Next Weekend: Warming Up; Storms Return


Temperatures will gradually warm up late this week as the upper level low gradually weakens and exits the region. Mostly sunny skies are expected for Wednesday with temperatures reaching the upper 70s to lower 80s across the area, approaching 85 degrees in the immediate NYC area. Warmer temperatures are expected for Thursday, with highs reaching the mid to upper 80s for most places, reaching 90 degrees in parts of the immediate NYC area.

By the late week into next weekend, a massive surge of heat will move into the central and southern US, with widespread 100-110+ degree temperatures spreading across the southern US and into parts of the Ohio Valley and the southern Mid Atlantic regions. The area will be near the northern edge of this very warm air mass, with 850mb temperatures close to 20C. With the area near the gradient, however, there is also going to be a risk of thunderstorms during this time frame, which is likely between at least Friday through Monday. Temperatures are generally expected to be in the mid to upper 80s across the area with the drier/sunnier days reaching the 90s in parts of the area, especially west/SW of NYC, with a risk of thunderstorms each day. Not every day is expected to have rain, although the potential is there for at least some days to bring thunderstorms. Stay tuned for more information on the outlook for next weekend.

June 25, 2012 Morning Update


NOTE: Regular daily discussions, along with updated 5-day forecasts for the entire area, will resume starting tonight.

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10:35 AM: A line of heavy rain and thunderstorms, containing frequent lightning and hail in some areas, moved through NYC earlier this morning and is now over Long Island and southern CT. Based on radar estimates, northern NJ mostly missed the storms, with most areas seeing less than 1/4 inch except for NE NJ, with up to 1/2 inch in SE NY and 1/2 to as much as 2 inches in NYC, Long Island, and southern CT.

This line of storms will continue to move out, although the cold front itself is still to the west, slowly approaching. The front will move through NYC around the early afternoon hours, with additional scattered thunderstorms possible especially from NYC and further east. Some of the afternoon storms could be strong and/or severe, although the afternoon storms should be less widespread than the storms observed this morning. Temperatures will reach the lower to mid 70s inland and the mid to upper 70s across the rest of the area.

The next full discussion will be posted tonight, with more information about the thunderstorm and brief heat potential for next weekend.

Sunday, June 24, 2012

June 24, 2012: Rain, Storms Return Tomorrow



Forecast Highlights:



- Rain, strong storms return tonight through Monday noon
- Chilly temperatures briefly return for Tuesday
- Brief heat surge likely in the late week/weekend
TROPICS: Debby defies forecast, now targets Florida


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June 23 and 24 Observations:


Following Friday's storm activity, Saturday (June 23) had mostly sunny skies across the area as a high pressure moved through the region. A cooler air mass moved in, although temperatures failed to significantly cool down, with high temperatures reaching the lower to mid 80s inland and the mid to upper 80s across most of the immediate NYC area and Long Island. The warmest temperature was 88 degrees in Newark.


With a high pressure still in place across the region on Sunday, along with a similar set up and little variation in the 850mb temperatures, highs were similar to those of Saturday but ending up slightly cooler, reaching the lower to mid 80s across most of the area with upper 80s in parts of the immediate NYC area, especially near NE NJ. Newark had the warmest temperature again with a high of 88 degrees.




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Tonight / Tomorrow Outlook:


As of this evening, rain has already moved into the area earlier than expected, although the rain will remain light for the main part. As the cold front approaches from the west, additional rain and thunderstorms will form late tonight into Monday morning, with the rain expected to be heavy at times with high precipitable water values. Windy conditions are also possible along with the rain. As the cold front moves through in the afternoon and evening, scattered strong thunderstorms are expected, especially over Long Island and southern CT. High temperatures will reach the lower to mid 70s inland and the mid to upper 70s across the rest of the area. An update regarding the rain will be posted on Monday morning.


Tuesday - Next Week: Chilly, Then Warming Up


Behind the trough, an upper level low will move into the region, with a chilly air mass in the region resulting in widespread below average temperatures. Partly cloudy skies are expected on Tuesday with a risk of an isolated afternoon shower and high temperatures only reaching the upper 60s to lower 70s inland and the lower to mid 70s across the rest of the area. With the ULL slowly moving out, temperatures will gradually warm up, reaching the mid to upper 70s inland and in Long Island/S CT and the upper 70s to lower 80s in the immediate NYC area on Wednesday. Mostly sunny skies will return for Thursday with highs in the lower to mid 80s across the area.

A brief yet strong surge of heat will move into the region on Friday and parts of the weekend, with temperatures reaching and/or passing 100 degrees in parts of the southern Mid Atlantic. The area will be in the northern edge of the warm air mass and will have less of an impact, although at least one hot day is possible, which appears to be either Friday or Saturday, when temperatures may have the potential of passing 90 degrees in parts of the area. There is the potential for scattered thunderstorms at some point during the weekend associated with the next cold front, although there is still uncertainty with the timing of the cold front. Stay tuned for tomorrow's update for more information on next weekend's outlook.


Tropics: Debby Defies Forecast, Goes Towards Florida




While models sometimes have trouble handling tropical cyclone tracks, the model performance for Debby could not have been much worse than it was; the spread for Debby's track went all the way from a due west track to a due east track. As of yesterday, some took it west towards Texas, others took it due north into Louisiana, and others had a northeast track taking the storm into Florida and then offshore. Yesterday, the majority of the model guidance was leaning with the west track; the GFS was the only major model to take the storm northeast into Florida, but half of its ensemble members were also supporting the western track. Despite the official outlook for a western track, however, Debby continued to slowly drift to the northeast, with the models adjusting from a west to a north track throughout the day while the GFS remained steady with a Florida landfall. The models are still not in an agreement regarding the track, with some taking it due north into western Florida and others taking it northeast, but at least the latest forecasts are much closer to an agreement than yesterday's mess. With Debby still drifting NE and the models shifting east, it is apparent that yesterday's expectation for a west track will end up incorrect, with my new forecast now supporting a Florida landfall within the next 48 hours. Debby will likely remain a moderate to strong tropical storm when it makes landfall in Florida, with a continued slow NE/NNE track likely. With Debby's slow motion, additional flooding will continue to take place in northern/central parts of Florida.

Saturday, June 23, 2012

6/23/12 Tropics: Tropical Storm Debby Forms


5:00 PM Tropics Update: Debby Forms

Invest 96L in the Gulf of Mexico continued to become somewhat better organized, and as of 5 PM is now listed as Tropical Storm Debby, the 4th named storm of the year's Atlantic hurricane season. The remarkably odd season continues once again as according to the National Hurricane Center, Debby sets the record for the earliest Atlantic 4th named storm in recorded history, surpassing Hurricane Dennis of 2005 by nearly 2 weeks. General Atlantic conditions, including a developing El Nino, are pointing to more of an average season, and an early start to a hurricane season does not guarantee that the rest of the season will be active as well, although the possibility is there that the season may end up somewhat more active than currently expected. More information on this will be posted with the updated hurricane season outlook, which if current trends continue may be completed earlier than August 1st, the date I am currently planning on posting the outlook.

More information on the tropics can be found in the Tropics page, which will be updated this evening with more information about Debby. The 5-Day Forecast is currently in the process of being updated.

June 23, 2012: After Storms, Dry Weekend


Forecast Highlights:


- Seasonable, dry weekend coming up
- Cold front results in rain, storms on Monday
- Cooler temperatures for first half of next week
- TROPICS: Tropical storm about to form in Gulf of Mexico


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Yesterday's Storm Overview:


During the day yesterday and into the evening, the NYC area observed its most widespread strong to severe weather outbreak of the year so far, ahead of a cold front that ended NYC's first official heat wave of the year. Following temperatures surging into the upper 80s to mid 90s in the morning hours with humid conditions, strong to severe thunderstorms rapidly developed over New York City around 1-2 PM, with the storms resulting in very heavy rain, strong winds which resulted in wind damage in parts of the city and western Long Island, and some hail. The first round of thunderstorms focused specifically on New York City, Nassau county, and parts of Suffolk county.

While the first round was ongoing, clearing in the cloud cover took place west of the city as scattered storms approached from Pennsylvania. As these storms ran into an outflow boundary drifting west through New Jersey, rapid storm development took place over interior northern NJ around 4-5 PM, resulting in a line of strong thunderstorms that moved through the rest of SE New York/NE New Jersey and into New York City. The strong thunderstorm event concluded after the line moved into NYC and fell below severe levels, although occasional rain lasted until close to midnight in some areas. Wind and tree damage was reported in parts of northern NJ, NYC and western Long Island, where the worst of the storm activity in the area took place. Storm activity was also notable to the south of the area, where storms frequently moved over parts of southern New Jersey from the afternoon through the overnight hours, resulting in rain locally over 3-4 inches.

Following the cold front, a high pressure will move through for the weekend, resulting in mostly sunny skies and seasonable temperatures, in the lower to mid 80s. By early next week, a cold front will move through with rain and some thunderstorms. Cooler temperatures are expected again for the first half of the week, although a gradual warming trend will take place leading up to next weekend.


Weekend Outlook:


With a weak high pressure moving in, mostly sunny skies are expected for this weekend along with seasonable temperatures. Highs will reach the lower to mid 80s inland, mid to upper 80s in the immediate NYC area, and the lower to mid 80s in Long Island/S CT.


Next Week: Rainy, Then Chilly


The heat wave observed late in the week was only an interruption in the pattern; as ridging returns into Greenland and parts of Canada, a trough will once again lock into the region, with a strong upper level low dropping into the region, resulting in another round of colder than average temperatures that resemble spring more than summer. Areas of rain and thunderstorms, heavy at times, will move through between Sunday night, after at least 1-2 AM, into Monday afternoon. The early timing of the cold front will limit severe thunderstorm potential, although some of the storms could be strong. Temperatures will then reach the mid to upper 70s for highs across most of the area on Monday.

A much cooler air mass will move in behind the front as the upper level low moves into the Northeast region. Temperatures on Monday night will be unusually chilly for this time of the year, dropping into the lower to mid 50s inland and the mid 50s to lower 60s across the rest of the area. Tuesday will be chilly compared to average as well, with partly cloudy skies and highs in the lower to mid 70s inland and the mid to upper 70s for the rest of the area.

Following the departure of the upper level low, a strong ridge accompanied by a very warm air mass will spread further east. While the strongest heat will stay to the south of the region, there will be a gradual moderation in temperatures throughout the rest of next week, with temperatures gradually rising into the 80s in the second half of next week with dry conditions likely. Stay tuned for more information on next week's outlook.


Tropics: 4th Named Storm About To Form


The Gulf of Mexico, mentioned in my June 12th update as being at risk for tropical cyclone development in the June 19-25 time frame, is seeing activity picking up with Invest 96L slowly moving through the central Gulf of Mexico. 96L is expected to soon develop into a tropical depression or storm; should it be named, which is the expectation, it will be named Debby, the 4th named storm of this year's hurricane season. This year's Atlantic hurricane season is already off to an unusual start, with Alberto forming unusually early, Beryl marking the first time in over a century that 2 named storms formed in May, and Chris becoming a hurricane at an unusually northern latitude considering the time of the year and the cool sea surface temperatures. The expected formation of a tropical storm will make this one of the earliest 4th named storms on record in the Atlantic Ocean. There is still some uncertainty with exactly where the invest, soon to be a tropical storm, will end up, although at this time it is likely to take a track further west, with the Gulf coast from western Florida to Texas at risk of a tropical storm or hurricane landfall.

**6/23/12 Morning Update**


The update originally planned for last night has been delayed due to other work. As of now the update, including a summary of yesterday's storm activity, should be completed by later this afternoon, with another forecast to be posted tomorrow at some point during the day. Regular daily updates should be resumed by Monday, June 25.

Friday, June 22, 2012

June 22, 2012 Storm Updates


Updates will be posted here on the strong to severe storms expected to affect the area later today. Updates will be posted both here and on twitter (blog updates can also be found below; more short updates can be found on tweeter archive).




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Blog Storm Updates:




6:50 PM: The line of strong thunderstorms that affected northern NJ, SE NY, NYC and southwestern CT over the last hour is now weakening as it enters Long Island, but is still capable of producing heavy rain and thunder. All storms in the area are now below severe levels and will continue to weaken as they move into the rest of southern CT and Long Island.

This is the last storm update for today. The next full update will be posted tonight, with an updated 5-day forecast, as well as an update on the upcoming heavy rain and thunderstorm event for late Sunday night into Monday and the chilly temperatures that will follow for the rest of next week.


5:05 PM: Widespread storm development is now taking place north/west of the city, especially focusing over interior parts of the area. Strong to low-end severe cells are currently affecting Rockland county, NY, and will move into northern Bergen and Westchester county. Another area of strong storms is near Sussex/Warren counties and will move east into Morris county. These storms will continue to move ESE through the evening hours, eventually approaching eastern NJ and NYC.



3:40 PM: With the original area of strong/borderline severe storms moving into Suffolk county, additional storm development is starting to take place further inland associated with the second round of storms. A strong storm popped up over Sussex county ahead of storm development in interior SE NY and NW Connecticut, with additional strong storm development likely to expand shortly into interior northern NJ and SE New York. Any storm that forms with the second round, which will mostly focus north/west of the city, will be capable of producing strong wind gusts, heavy rain and small hail.



3:15 PM: Severe storms continued to develop over NYC over the last hour with very heavy rain, strong wind gusts and some hail, and are now moving into Nassau and Suffolk counties in Long Island. Meanwhile, clearing in the cloud cover is taking place west of the city ahead of the next round of storms, currently in central/eastern Pennsylvania. This round of storms will continue to move east, affecting some areas west of NYC later this afternoon and evening.



2:20 PM: Over the last 20 minutes, widespread storm development began to take place near NYC. A strong storm is located near Nassau county, and will continue to move SE through the rest of Nassau county, spreading heavy rain and gusty winds. Another strong storm is near Jersey City, NJ, and will move NE over the next half hour into Manhattan and Queens in NYC. This area of storms will continue to spread and affect the rest of NYC and parts of Long Island.

The storm development near NYC is only one part of the outbreak for today. Additional storms will continue to fire up towards central/eastern Pennsylvania, with additional storms expected later today for the western half of the area.


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12:25 PM: Storms, Some Severe, To End Heat Today

As of late this morning, most of the area is experiencing mostly cloudy to cloudy skies, although with a very warm air mass still in place, temperatures are quickly heating up, and are already in the 91-94 degree range in NYC except for Central Park. The approaching cold front, however, will limit the temperature rise, with widespread thunderstorms expected.

Other than isolated showers, there is not much activity currently taking place across the region. Later this afternoon towards 2-4 PM, however, widespread thunderstorm development is expected to take place over New Jersey and eastern Pennsylvania, gradually shifting east throughout the late afternoon and evening hours. These storms will be capable of producing heavy downpours and strong wind gusts. Stay tuned for storm updates to be posted later this afternoon.

Thursday, June 21, 2012

June 21, 2012: Severe Storms Possible Tomorrow


Forecast Highlights:


- Storms, possibly severe, to end heat tomorrow
- Mostly sunny, dry weekend expected; temperatures in 80s
- Colder pattern returns by early next week with some rain
- After today, no additional big heat in sight


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Due to a busy schedule, the 5-Day Forecast page was not updated tonight. A full discussion will be posted tomorrow morning with more information on severe weather for tomorrow.

If necessary, storm updates will be posted on Friday afternoon/evening, both in the blog and in the new NYC Area Weather page in tweeter.

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Today's Observations:


Another day of heat and humidity was observed with 850mb temperatures up to 20-21C along with mostly sunny skies. Temperatures were very similar to those of Wednesday, ending up slightly warmer in some areas, reaching the mid 90s inland, lower to mid 90s in Long Island/S CT, and the mid to upper 90s in the immediate NYC area. Newark came very close to 100 degrees, reaching a peak temperature of 99 degrees. Record highs were broken in LaGuardia, JFK, Islip and Bridgeport; Newark came within 1 degree of its record of 100 degrees set in 1953.


LaGuardia, NY
98 degrees (previous record: 97 degrees - 1953)
JFK Airport, NY
97 degrees (previous record: 95 degrees - 1988)
Islip, NY
95 degrees (previous record: 93 degrees - 1988)
Bridgeport, CT
96 degrees (previous record: 95 degrees - 1953)



Tomorrow's Outlook: Severe Storms Possible


With a cold front approaching, temperatures will warm up again tomorrow morning, peaking early in the upper 80s to lower 90s inland and in Long Island/S CT, with lower to mid 90s in the immediate NYC area and parts of Long Island closer to NYC. With the cold front, occasional thunderstorms, some of them strong/severe, are expected to affect the area especially after 1 PM. These storms may be capable of producing heavy rain, strong wind gusts and potentially hail. The storms are expected to end in the evening hours with clearing skies and dropping temperatures overnight.


Forecast Overview:


With the cold front moving offshore, mostly to partly sunny skies and temperatures in the lower to mid 80s will return for the weekend. By Monday, however, a strong upper level low will drop into the region as another ridge builds into Canada, once again locking a trough into the region while keeping the heat well to the west. Occasional rain and possibly thunderstorms are expected on Sunday night into Monday, followed by drier conditions for Tuesday and Wednesday with occasional sunshine, a risk of scattered showers, and below average temperatures, only reaching the lower to mid 70s for highs across most of the area. While no significant heat will build into the region, a gradual moderation in temperatures is likely for the second half of next week. Stay tuned for more information on the longer range with tomorrow's update.

June 20, 2012: Heat, Storms, Then Colder


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Forecast Highlights:

- One more day of heat; 95-100 degree heat returns Thursday
- Scattered storms, some heavy, to end heat on Friday
- Return to cooler pattern starting early next week

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Today's Observations:

As a very warm air mass moved into the region, with 850mb temperatures surging up to 20 degrees Celsius, mostly sunny skies, and winds generally coming from the west, the hottest day of the year so far was observed, with temperatures surging into the mid 90s inland, mid to upper 90s in the immediate NYC area, and the lower to mid 90s in most of Long Island and southern Connecticut, although parts of Long Island reached the mid-upper 90s range. New London in SE Connecticut barely missed the 90 degree mark, peaking at 89 degrees. Below are the record highs broken today:


LaGuardia, NY
98 degrees (previous record: 96 degrees - 1953)
JFK Airport, NY
94 degrees (previous record: 93 degrees - 1995)
Newark, NJ
98 degrees (previous record: 97 degrees - 1953)

Hotter temperatures are possible for tomorrow, with highs reaching the mid 90s to nearly 100 degrees from NYC and further north/west, although a cold front on Friday will end the heat along with bringing a risk of scattered thunderstorms, possibly heavy, during the afternoon hours. Temperatures won't immediately cool down, staying in the lower to mid 80s during the weekend with dry conditions, although with a trough returning into the region, a colder pattern will develop for next week.


Tomorrow's Outlook:


Tomorrow will be the last very hot and humid day of this heat surge, with temperatures again surging into the mid to upper 90s from NYC and further north/west, and the lower to mid 90s in most of Long Island/S CT, reaching the upper 90s closer to NYC. Temperatures in parts of the immediate NYC area may reach 100 degrees, although most places will be closer to the upper 90s for highs. Heat index values are again expected to reach the 100-105 degree range in the immediate NYC area while approaching 100 degrees inland.


Friday - Weekend: Storms, Then Seasonable


With the cold front approaching, temperatures will quickly warm up again on Friday morning, with temperatures peaking earlier than usual in the upper 80s to lower 90s inland, in Long Island/S CT, and the lower to mid 90s in the immediate NYC area. Scattered thunderstorms, some of them heavy, are expected with the cold front especially during the afternoon and evening hours. More information will be posted on Friday's storm potential with Thursday's update.

Behind the cold front, a cooler air mass will move in, although temperatures will remain close to average, reaching the lower to mid 80s across the area with mostly to partly sunny skies expected. No rain is expected during the weekend, although some rain is possible into Sunday night.


Next Week: Trough Brings Colder Than Average Temperatures


With an upper level low dropping into the region, another round of below average temperatures accompanied by some rain and clouds is expected for most of, if not all of next week. The most extreme model solution today came from the 6z/12z GFS runs which took a strong low pressure up the coast with a strong trough covering the entire region. The GFS solution is likely exaggerated, although there is increasing confidence in a low pressure moving through the region on Monday with periods on rain and possibly thunderstorms between Sunday night and Monday night. For now, I went with a 65% chance of rain for Monday in the 5-Day Forecast page, although as long as there's no significant changes this probability will likely be increased with Thursday's update. Temperatures are expected to be below average as well, likely ending up in the mid 70s range, possibly a bit cooler or warmer depending on the exact amount of cloud cover and rain.

Following Monday's rain event, a strong trough to the magnitude of what some of the earlier model runs showed is not very likely, although colder than average temperatures will still continue, with highs through mid-late next week staying in the 70s, possibly in the lower end of the 70s depending on cloud cover and rain chances. Beyond the middle of next week, no significant heat is expected for the region for the medium range, although some moderation in the cool air mass is possible. Stay tuned for more information on the longer range.

Wednesday, June 20, 2012

June 20, 2012 Noon Update


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3:55 PM: Record Broken In Newark


As of this afternoon, Newark, NJ broke its daily record temperature, reaching a high of 98 degrees so far. Temperatures may still climb a degree or two before starting to drop later this afternoon. The rest of the area is also seeing hot temperatures, with widespread mid 90s inland, mid to upper 90s in the immediate NYC area, and upper 80s to mid 90s across most of Long Island and southern Connecticut. With the humidity, heat index values above 100 degrees have already been observed in parts of the area, exceeding 105 degrees in some places. Similar conditions are expected tomorrow with slightly hotter temperatures, potentially reaching and/or slightly passing 100 degrees in parts of the immediate NYC area.

The next update will be posted tonight, with more information about the heat for tomorrow and Friday, the thunderstorm potential for Friday afternoon with the cold front moving through, and additional wet weather for the start of next week.

June 19, 2012: Hot, Humid Ending To Week


Today's Observations:


The last of the seasonable to colder than average days was observed on this day, with temperatures reaching the lower to mid 70s in Long Island/S CT and the mid 70s to lower 80s from NYC and further north/west. Partly to mostly cloudy skies were observed again, with occasional breaks in the cloud cover throughout the day.


Wednesday - Thursday Outlook:


A surge of heat currently located over the Great Lakes and Midwest regions is moving east towards the area, bringing a 3 day heat wave containing some of the hottest temperatures of the entire summer, which is shaping up to be a chilly one. The main difference with the expected set up is a developing low pressure in the north central US; some models, especially the NAM/GFS, noticeably mishandled the development of this low pressure even as late as this morning, which is resulting in a trend towards a storm slower to develop, and thus a slight delay in the warm air mass. This may point to very slightly cooler temperatures for tomorrow, although the heat is still expected away from the immediate coast, with temperatures rising into the lower to mid 90s inland, upper 80s to mid 90s in Long Island/S CT, and mid to upper 90s in the immediate NYC area, locally reaching 100 degrees just west of the city. Heat index values in the immediate NYC area are expected to reach the 100-105 degree range and are expected to approach 100 degrees further inland.

Thursday will still be the hottest day, with temperatures approaching or reaching 100 degrees near NYC. Temperatures will be quick to rise, already reaching the mid-upper 80s near NYC by 8 AM and the mid 90s by 11 AM. Highs are expected to reach the mid 90s inland, upper 90s in the immediate NYC area except for the coastal areas, and lower to mid 90s in Long Island/S CT with areas closer to NYC reaching the upper 90s. Temperatures in parts of NE NJ may reach and/or slightly pass 100 degrees. As with Wednesday, heat index values will reach 100-105 degrees in the immediate NYC area while approaching 100 degrees further inland.

The change in the expected set up mentioned earlier results in a delayed cold front, which is now likely to move through during the day on Friday. As a result, the first part of Friday may once again start out hot and humid, with temperatures quickly rising again in the morning; depending on cloud cover and rain, temperatures may reach 90 degrees in the immediate NYC area as early as 11 AM. Afterwards, scattered showers and thunderstorms are expected during the afternoon, and depending on the exact timing, which could still be a bit slower than currently expected, temperatures are likely to reach the lower to mid 90s in the immediate NYC area, with upper 80s to lower 90s inland and further east.


Longer Range: Chilly Pattern Returns


As yesterday's discussion mentioned, the current heat surge is only an interruption in the chilly pattern observed since the start of the month, with blocking and Greenland/Canada ridging once again expected to set up in the medium to long range. With the blocking pattern returning, a strong upper level low for this time of the year will drop into the region, bringing below average temperatures and the potential for rain during early-mid next week. The models are in disagreement with the development of any low pressure and the intensity of the trough, with the CMC model the weakest and the ECM model the most extreme. The ECM solution is likely exaggerated, although cooler temperatures, returning into the 70s for highs, with more cloud cover and the potential for some rain is expected for early-mid next week.

Tuesday, June 19, 2012

June 18, 2012: 100 Degrees Possible This Week


Forecast Highlights:


- Very Hot Wednesday/Thursday; 95-100 Degrees Expected
- Heat Index up to 105 Degrees Possible
- Chilly Pattern to Return Afterwards
- First cooler than average month in over a year possible


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Today's Observations:


Another mostly cloudy day was observed today with an area of dissipating showers and thunderstorms approaching from the west. Temperatures were similar to those of yesterday, peaking in the upper 60s to low 70s in Long Island/S CT and the lower to mid 70s from NYC and further north/west, which was slightly cooler than expected. A brief yet strong surge of heat will move through the region on Wednesday and Thursday, with temperatures approaching 100 degrees in the immediate NYC area, although the heat will quickly move out, with a chilly pattern returning by next weekend.


Tomorrow's Outlook:


The last of the chilly days prior to a brief interruption in the colder than average pattern will take place tomorrow, with partly cloudy skies expected and temperatures reaching the mid to upper 70s in Long Island/S CT and the lower to mid 80s from NYC and further north/west. South/SSW winds are expected.


Wednesday - Friday: Hot, Humid; 100 Degrees Possible


The surge of heat currently in the central US will move into the region, resulting in the hottest temperatures of the year until this point. Depending on the pattern for the rest of the summer, it is also possible that this may be the hottest heat surge of the entire year. 850mb temperatures up to 20-22C are expected to move east from the Great Lakes into the Northeast region, with the warmest air mass overhead during Wednesday and Thursday. Both days are expected to bring west winds with mostly sunny skies and dew points close to 70 degrees, which all support the heat and humidity expected for these two days.

Wednesday will start out with temperatures in the 70s in the morning hours, quickly surging into the lower to mid 90s in most of Long Island/S CT and the mid to upper 90s from NYC and further north/west, possibly reaching 100 degrees in some areas just west of NYC. The hottest temperatures are expected in the immediate NYC area. With dew points close to 70 degrees, the heat index is expected to reach the 100-105 degree range across most of the immediate NYC area while getting close to 100 degrees further inland. Temperatures will be slow to decline, and are still likely to be near 90 degrees at 8 PM.

Thursday will be the hottest day, ending up slightly hotter than Wednesday. After mild overnight lows, with temperatures barely dropping below 80 degrees in NYC, temperatures will be quick to rise, already reaching the mid 90s in the immediate NYC area by noon. Temperatures are expected to reach the lower to mid 90s across most of Long Island/S CT, slightly cooler near the coast and hotter closer to NYC, with upper 90s in the immediate NYC area excluding coastal areas and mid to upper 90s further inland. Temperatures may reach 100 degrees again in parts of the immediate NYC area, with the heat index ending up in the 100-105 degree range, possibly a bit higher in some areas. The 18z NAM model posted to the left from the Pennsylvania State University E-Wall (direct link to 18z NAM) shows a set up supportive of temperatures getting close to 100 degrees, with west winds and 850mb temperatures near 20C; the frame posted above for Thursday afternoon shows a small area of 100 degrees in NE NJ.

As with Wednesday, temperatures will be slow to drop in the evening, with 90s still likely in the immediate NYC area by 8 PM. Later overnight, however, a cold front will move through the region, bringing a cooler air mass further southeast, although little shower/thunderstorm activity is expected with this cold front. Overnight lows are expected to end up in the low to mid 70s for most of the area, with temperatures on Friday reaching the mid to upper 80s for most places, possibly getting into the lower 90s in the immediate NYC area.


Longer Range: Cooler Pattern Returns


**First colder than average month since early 2011 possible**


The most recent winter season was accompanied by persistently above average temperatures, well above average in some cases, peaking in March when a record surge of warmth affected a large part of the United States. Since the winter, however, the pattern has flipped, and blocking is gradually becoming more frequent over the northern latitudes, especially near Greenland; during the December-February time frame, there was almost no ridging to be found anywhere near Greenland, yet over the last month positive 500mb height anomalies have been observed along with a strong 576 dm block that remained stationary over Greenland earlier in the month. Blocking patterns in favorable locations, especially over Greenland, tend to result in cold/snowy patterns during the winter while suppressing the heat in some cases during the summer. With the blocking pattern observed this month, along with frequent rain and cloud cover and the lack of sustained ridging as most of the heat was forced to the west and north, staying in the central US and Canada, the entire East Coast is at least slightly cooler than average, with Central Park averaging out 0.5 degree below normal in the June 1-18 time period.

A surge of strong heat is expected for 2-3 days with temperatures as much as 15-20 degrees above average, although with ridging again expected to build into Greenland and Canada, the surge of heat is only an interruption in the pattern as opposed to a pattern change, with the pattern through early July and likely beyond expected to feature more troughs than ridges. There does not appear to be much strong cold air around, meaning that most days for the last 9 days of June will likely end up with temperatures generally close to average, possibly a bit above/below at times, but especially during rainy and cloudy days, as possible with next Monday, larger negative departures are possible. With the heat balancing out the cool days observed so far, June will end up close to average, ending up either slightly warmer or cooler than average, both of which are reasonably possible. Should June end up on the cooler side, it would make this month the first time since early 2011 that a colder than average month has been observed in New Jersey. Stay tuned for more information on the longer range.

Monday, June 18, 2012

June 17, 2012: Heat For Wednesday, Thursday



Forecast Highlights:



- Clouds, Chilly Temperatures Continue Tomorrow
- Heat Briefly Moves In Wed/Thurs; 95-100 Degrees Expected
- Chilly Pattern Potentially To Return


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Today's Observations:


More clouds than originally expected were observed today, with mostly cloudy to cloudy skies observed across most of the area resulting in slightly cooler temperatures than expected. Highs ended up in the lower to mid 70s inland, lower 70s in the immediate NYC area, and the mid to upper 60s across most of Long Island/S CT.

Partly to occasionally mostly cloudy skies will continue through Monday as well, with temperatures similar to those of today, if not slightly warmer. The stretch of slightly cooler than normal temperatures will not last for much longer, however, as a brief yet intense surge of heat moves into the region, producing 95-100 degree heat for parts of the area on Wednesday and Thursday. The heat won't last for long as well, with signs of another chilly pattern developing for the longer range.


Monday - Tuesday Outlook: Starting To Warm Up


With clouds and scattered showers/storms approaching from the west, partly to occasionally mostly cloudy skies will continue on Monday, with highs reaching the lower to mid 70s from NYC and further north/west and the mid 60s to lower 70s in Long Island/S CT. Isolated showers are possible in the westernmost parts of the area, although the approaching rain in Pennsylvania will collapse before reaching the NYC area. Partly cloudy skies are expected for Tuesday with temperatures warming up into the mid 70s across most of Long Island/S CT and the upper 70s to lower 80s from NYC and further north/west.


Wednesday - Beyond: Hot, Then Cooler


A very warm air mass containing 850mb temperatures up to 20-22C will move into the region, providing the area with the biggest heat of the year so far. WSW/SW winds will develop for both days with mostly sunny skies, easily supporting the heat modeled for this time period. Wednesday and Thursday will be the hottest days, with temperatures surging into the mid to upper 90s from NYC and further north/west, with upper 80s to mid 90s in most of Long Island/S CT. It is not out of the question that parts of the immediate NYC area reach or get very close to 100 degrees. This time period isn't expected to be very humid, although the heat index is likely to reach the lower 100s in parts of the immediate NYC area.

It now appears that the cold front will move through around Friday, meaning that this surge of heat falls short of reaching the criteria for an official heat wave, as only 2 consecutive days will end up with 90+ degrees. The cold front, however, appears to be more dry than wet, with only a risk of scattered thunderstorms on Friday. Following the cold front, the development of strong ridging over Canada and Greenland as well as an incoming trough will result in another chilly pattern, with temperatures likely near or below average for a while starting on Friday/Saturday while the core of the heat shifts into the Southeast.

Saturday, June 16, 2012

June 16, 2012: 95+ Degrees Later This Week


Forecast Highlights:


- Slightly Cooler Than Normal Temps Through Tuesday
- Heat Surge, 95+ Degrees For Wednesday/Thursday
- Colder Temperatures Return Next Weekend


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Today's Observations:


Mostly sunny skies were observed again across most of the area as a high pressure continues to remain spread out across the region, with temperatures ending up similar to those of yesterday, in the upper 70s to lower 80s from NYC and further north/west and the mid to upper 70s across most of Long Island/S CT, although Montauk in far eastern Long Island reported a high of 69 degrees.

Temperatures will slightly cool down tomorrow and on Monday with increased cloud cover and the potential for an isolated shower in the far western parts of the area, although with a surge of heat moving into the region, the hottest temperatures of the year so far will be observed on Wednesday and Thursday, with widespread 90+ degrees covering the area, getting as high as the 96-100 degree range along the Washington DC-NYC corridor.


Sunday - Tuesday: Slightly Cooler, A Bit Cloudier


With a SE flow developing for Sunday and Monday, slightly cooler temperatures are expected. Highs will reach the mid to possibly upper 70s from NYC and further north/west, although the biggest impact will be felt in Long Island/S CT, where most places will reach the upper 60s to lower 70s for highs. Areas closer to the coast may see highs in the mid 60s. Partly cloudy skies are likely on both days, especially further east on Sunday, and further west on Monday ahead of a weakening cold front that will produce some clouds but very little, if any rain. Temperatures on Monday will be similar to those of Sunday, possibly a little warmer. Temperatures will begin to warm up on Tuesday as a warm air mass approaches, with high temperatures in the mid 70s to lower 80s across the area.


Wednesday - Beyond: Big Heat, Then Cooling Down


As mentioned over the last few days, the first potential heat wave of the season will take place on Wednesday and Thursday, possibly extending into Friday. With 850mb temperatures up to 20-22C moving into the region with a west wind developing, temperatures will easily surge above 90 degrees for both days across most of the area, excluding the immediate coast, with temperatures from NYC and further north/west reaching the mid to upper 90s. In the warmer case scenario, parts of the immediate NYC area may even get very close to 100 degrees. Mostly to partly sunny skies are expected for both days with no rain.

The next cold front will move through the region on Friday, ending the heat. The exact timing is uncertain, as the ECM has the frontal passage closer to Thursday while the GFS brings the front through on Friday. At this time, I am leaning with the slower timing for the passage, with highs again reaching the 80s, although the timing will determine whether highs reach 90 degrees in NYC or not, thus determining whether the heat surge meets the requirement for a heat wave, which is 3+ consecutive days of 90+ degrees. There is the potential for thunderstorms with the cold front on Friday, possibly extending into early Saturday should the front end up slower although at this time Friday is more favored for the storm potential. Afterwards, there are increasing signals for another trough to build into the region, bringing the area back to the same chilly, occasionally cloudy and wet pattern observed during the first half of the month.

Friday, June 15, 2012

June 15, 2012: Heat Builds In During Mid Week


Forecast Highlights:


- Seasonable through Tuesday; coastal clouds/fog on Sunday/Monday
- Heat builds in for mid-late week


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Today's Observations:


With a high pressure still in place, today ended up as another mostly sunny day with mild temperatures observed across the entire area, peaking in the mid to upper 70s for most, with lower 80s in parts of northern NJ/SE NY and lower-mid 70s in parts of Long Island, which verified today's expectation from the 5-Day Forecast page.

Similar conditions will continue through at least Tuesday, with  Sunday/Monday the main exception due to slightly increased cloud cover, cooler temperatures and possible fog especially closer to the coast, although a heat surge will build into the region between Wednesday and Friday, bringing 90+ degree heat for parts of, if not most of the area.


Saturday - Tuesday: Slightly Cooler, Then Warmer


Similar conditions are expected for tomorrow compared to those of today, with mostly sunny skies and highs generally in the mid 70s to lower 80s range. On Sunday and Monday, however, a SE wind is expected, with cooler temperatures, partly cloudy skies, and possible fog closer to the coast. Temperatures from NYC and further north/west will remain close to average, peaking in the mid to possibly upper 70s, although Long Island and southern Connecticut will end up colder, with highs in the upper 60s to mid 70s, possibly slightly cooler closer to the immediate coast. Temperatures will warm up slightly on Tuesday as the wind transitions to more of a south/SSW than a SE direction.


Wednesday - Friday: First Heat Wave Potential


A very warm air mass will move into the central US early in the week, resulting in widespread 90-100 degree heat. With the ridge and the high pressure shifting east, with winds aloft switching to more of a west direction, the heat in the central US will move into the region as opposed to Canada, resulting in the first potential heat wave of the summer for the region. There is still the possibility that a back door cold front on Thursday/Friday may limit the heat for New England, although at least from NYC and further west/south, 90+ degree heat is expected during the Wednesday-Friday time frame; should the hotter case scenario verify, which is a reasonable possibility, temperatures may even reach the upper 90s to 100 degrees for highs. The next cold front is then likely to approach on Friday or the weekend, resulting in a risk of thunderstorms. Stay tuned for more information on the heat potential.

June 14, 2012: Heat Possible Late Next Week


Forecast Highlights:


- Seasonable Weather Through Tuesday
- Heat Potential Late Next Week; 95-100 degrees possible


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Today's Observations:


With yesterday's storm having moved out of the region, a high pressure moved in, bringing dry conditions again. More cloud cover was observed than originally expected, although temperatures were close to the forecast, reaching the lower to mid 70s in Long Island/S CT and the mid 70s to 80 degrees from NYC and further north/west.

This high pressure will stay in place through next week, providing the area with mostly to partly sunny skies and seasonable temperatures. By Wednesday, however, a large ridge in the central US will begin to spread east, resulting in the potential of the first heat wave of the year for the region.


Friday - Tuesday: Seasonable, Dry, Mostly Sunny


As mentioned with yesterday's discussion, with the high pressure in place, little variation is expected in the outlook. The main highlight will be an onshore flow during the weekend, with more cloud cover and lower temperatures near the coast, where highs will likely reach the upper 60s to lower 70s for most of Long Island/S CT while interior areas reach at least the mid 70s. Otherwise, mostly sunny skies will continue with highs in the lower to mid 70s in Long Island/S CT and the mid 70s to lower 80s from NYC and further north/west, with low 80s likely especially on Friday.


Wednesday - Next Weekend: Heat Wave Potential


Up until this point, there have been few heat spells in the region due to lasting influence from back door cold fronts in part due to a blocking pattern near Greenland, and an unfavorable ridge axis for heat, which sends the heat from the central US into Canada. By the middle of next week, another surge of heat will move into the central US, but with the high pressure shifting east without anything to completely push the heat into Canada, the heat is likely to move into the region for the first time since late May.

At this time, most of the models support the heat potential, with the ECM and the GFS bringing 850mb temperatures to 20C, which in typical summer heat waves would result in highs in the upper 90s to low 100s and is supported by this type of air mass that is modeled for the late week. The CMC keeps the heat mostly to the west, but has an offshore upper level low closer to the coast than the rest of the guidance. The 12z ECM also shows a back door cold front moving through on Thursday; while the possibility is there that a back door cold front comes through, with this set up it is unlikely to advance much south of New England, and even if one does come through at least a brief period of heat would still affect the region.

Although due to the time range, the specifics are still uncertain, there is an increasing probability of temperatures passing 90-95 degrees in parts of the region, including the area, on Wednesday, Thursday and possibly Friday. Should the warmest case scenario verify, with no back door cold front and 850mb temps near 20-22C, which is a reasonable possibility, temperatures may get as high as the upper 90s to even 100 degrees, although this part is still only a possibility and depends on the amount of sunshine, wind direction and where any back door cold front ends up. Stay tuned for more information on the heat spell.

Thursday, June 14, 2012

June 13, 2012: Dry, Seasonable Week Ahead


Forecast Highlights:


- Seasonable temperatures, no rain through mid next week
- Heat surge possibility late next week
- Tropics to possibly pick up in Gulf of Mexico


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Today's Observations:


The main part of the rain event moved out of western areas early in the morning and the rest of the area later in the day, with mostly cloudy skies and scattered showers. Rain totals ended up generally in the 0.75 to 1.25 inch range in northern NJ, 1/2 to 1.5 inch in southern CT; the heaviest totals were over Long Island where totals reached 1 to as much as 3 inches of rain. Highs reached the mid 60s to lower 70s in Long Island/S CT, which was close to the forecast, but the western parts of the area were warmer than expected, reaching the mid 70s to 80 degrees.

A large high pressure will stall over the region from tomorrow through most of next week, providing a long stretch of dry and mostly sunny weather. Temperatures will start out seasonable, although there is a possibility of a brief surge of heat by the end of next week.


Thursday - Tuesday: Sunny, Dry, Seasonable


After a pattern of clouds, rain and chilly temperatures that started following a large rain event in the end of April, a break from the pattern is taking place with a large high pressure moving into the East Coast and stalling in place. The current pattern favors the core of the heat staying towards the central US, with influence from back door cold fronts or upper level lows sending the central US heat into Canada, which has already seen more 85-90+ degree days than parts of the region, while the Mid Atlantic and Northeast continue to see temperatures generally near to below average. From June 1st through yesterday, monthly temperatures were slightly cooler than average; while it is likely that the month will once again end up warmer than average, it may have the smallest positive departure since the consecutive stretch of warmer than average months began following the cold winter of 2010-2011.

In this case, the high pressure will again stay to the west of the area, with a large heat wave building into the central US. With an upper level low offshore, seasonable temperatures will continue. A NE wind is expected for most of the time period during the day, with temperatures generally in the mid 70s in Long Island/S CT and the mid to upper 70s, occasionally lower 80s, from NYC and further north/west. Mostly sunny skies will continue through Tuesday with no rain expected.


Wednesday - Late Week: Heat Surge Potential


By the late week, especially on Thursday, there is a strong signal on the models for the strong central US heat to briefly spread east as the ridge weakens and shifts further east, with the high pressure aligned in a position more supportive of SW winds, which would bring the heat into the region. Should this scenario verify, this type of air mass and ridge would easily be capable of bringing temperatures into the 90s away from the coast. Up until this point, however, the models typically have exaggerated long range heat potentials, and any potential that showed up ended up being replaced by a back door cold front or a ULL keeping temperatures close to average, while the heat remained in the central US. In this case, however, with the axis of the heat temporarily shifting east with a further east high pressure, there is more support for the heat scenario than the previous warmth potentials and a larger probability of the heat verifying, although the heat potential is still not 100% certain yet. Stay tuned for more information on the late week outlook.

Other than the heat, the tropics may become active once again as mentioned with the previous update. This time period is still far enough away that the smaller details are uncertain, but especially with the large ridge over the US, there are signals pointing to possible tropical development in the Gulf of Mexico region, especially around the June 19-25 time frame. More information will be posted on that in the Tropics page as the time period approaches.

Wednesday, June 13, 2012

June 12, 2012: Seasonable Temperatures Continue


Forecast Highlights:


- Seasonable temperatures through next week
- After tomorrow, dry until next week


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Short Range Outlook:


As mentioned with this afternoon's update, rain moved into the area much earlier than originally expected, starting around 11 AM-12 PM as opposed to the mid to late afternoon hours. The rain is already clearing the western parts of the area, and will continue to move east, clearing most of the immediate NYC area by 3-4 AM, although the rain will remain stuck over Long Island and southern Connecticut for a longer period of time tomorrow.

Behind this system, a high pressure will build into the region with another heat surge moving into the central US and Canada, but influence from an onshore flow due to a further west high pressure as well as an offshore upper level low will keep dry conditions, fair skies and seasonable temperatures through the weekend and into parts of next week as well.


Forecast Overview:


With the pattern becoming quiet following the departure of the current storm, there is not much to talk about in tonight's discussion other than a long lasting stretch of seasonable temperatures and dry conditions. The rain will clear places west of NYC tomorrow morning and places east of NYC in the afternoon hours, with highs reaching the upper 60s to lower 70s in Long Island/S CT and the lower to mid 70s in the rest of the area, which is once again colder than average.


The high pressure will build in on Thursday and stick around into next week, providing mostly to partly sunny skies for this time period. With the high pressure not in the ideal location for heat, NE winds are expected with a cooler air mass, keeping temperatures close to average while the Great Lakes region experiences the worst of the heat. Temperatures will reach the lower to mid 70s in Long Island/S CT and the mid to upper 70s elsewhere on Thursday. With little changes expected in the weather pattern, similar conditions will continue through at least Tuesday or Wednesday next week with temperatures slowly warming up towards the end of the time period. As the ridge begins to shift east and break down, there is a possibility that a short lasting surge of heat moves through late in the week. Little, if any, rain is expected to fall through at least Wednesday.

Precipitation and severe weather across the region going into next week appear to be relatively quiet as well. The tropics are also quiet at this time in the Atlantic basin, although there is the potential for tropical development in the Gulf of Mexico/SE US region around the June 19-25 time frame.

Tuesday, June 12, 2012

June 12, 2012 Storm Updates



5:40 PM: Rain Started Much Earlier Than Expected



Contrary to the model guidance which for the main part suggested that the rain would start towards the afternoon and evening hours, rain moved into the western half of the area as early as 11-12 AM, with a steady light to moderate rain now falling across most of the area except for SE Connecticut. Radar estimates show that so far, at least 1/4 to 1/2 inch of rain has been observed west of NYC.

The rain is expected to continue falling into tonight with some occasional breaks, and may be heavy at times later tonight. The strong thunderstorms in western Pennsylvania are not expected to reach the area maintaining their current intensity, although rain should continue into at least the first part of the overnight hours. With a low pressure developing off the coast, mostly cloudy skies and scattered showers east of NYC will continue into tomorrow, with the rain clearing most of the area late tonight.

Stay tuned for more updates later tonight.

**No Update Posted 6/11/12**


Unfortunately, due to a busy schedule, I was unable to post an update tonight again. With a less busy schedule coming up, I should be able to resume daily updates starting on Tuesday.

Monday, June 11, 2012

June 10, 2012: Heavy Rain For Tuesday Night


Forecast Highlights:


- Cooler temperatures stick through next week
- Heavy rain risk for Tuesday night
- Still no true summer-like heat in sight


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The observations of the last few days will be added on Monday.


Tomorrow's Outlook:


Mostly sunny skies are expected across the area tomorrow with SE winds due to the back door cold front moving through, resulting in cooler temperatures near the surface. Highs will reach the lower to mid 70s in Long Island/S CT, mid to upper 70s in the immediate NYC area, and upper 70s to lower 80s inland.


Tuesday - Beyond: Heavy Rain, Then Dry And Seasonable


A cold front will approach the region on Tuesday, resulting in an area of heavy rain moving through the NYC area on Tuesday evening into early Wednesday. There is not much of a severe weather risk with this set up, as heavy rain will be the main risk, with amounts ending up in the 1-2 inch range for parts of the area with isolated amounts above 2 inches possible. Temperatures will slightly cool down on Tuesday, reaching the 70s across the area, slightly warming into the mid 70s to lower 80s on Wednesday with the warmest temperatures closer to NYC.

Beyond the mid week storm, another ridge will build into the central US, with an offshore cutoff low keeping cooler temperatures closer to the coast while the heat stays well to the west and north, as observed during most of the heat spells with the current pattern. While no widespread rain is expected, temperatures will generally remain seasonable, likely reaching the mid 70s to lower 80s range through the end of the week and likely into the weekend, which at this time does not appear to end up rainy.

Sunday, June 10, 2012

June 10, 2012 Updates


6:30 PM: Scattered Storms Developing


After temperatures peaked in the 80s for parts of the area today, isolated thunderstorms formed over NW NJ and interior SE NY. Most storms are below severe levels, producing heavy rain, although there is a severe thunderstorm that tracked from NW NJ to Morris county, where it produced strong winds and likely hail, and is currently tracking south headed into central NJ. The three other heavy thunderstorms are near central Sussex and north Passaic counties, and will move SSE into Morris and eastern Passaic counties over the next 1/2 hour. Otherwise, no widespread storm development is expected.



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8:50 AM: Isolated Storms Today


Despite the instability in place, storms failed to form yesterday afternoon, with cloudy skies and isolated showers taking place instead. Since then, the approaching cold front has stalled not too far to the north of NYC, and will continue to gradually move southwest throughout the day, passing NYC in the afternoon. As a result, Long Island and southern CT will see partly sunny skies today with highs peaking in the mid 70s to lower 80s. Ahead of the cold front, temperatures will quickly warm up from NYC and further west/south, reaching the lower to mid 80s in NYC and the mid to upper 80s in northern NJ, possibly reaching 90 degrees towards central NJ.

With the cold front moving through this afternoon, isolated storm development is possible especially west of NYC after 3 PM today. Any storm that does form will likely stay below severe levels but may contain heavy rain. Temperatures will cool down tonight with the cold front to the southwest, with highs staying in the 70s to lower 80s from Monday through Wednesday, with a locally heavy rain and thunderstorm event expected between Tuesday night and Wednesday. More information will be posted on the mid week storm with tonight's discussion.