May 30, 2013: Heat Wave Begins Today

Forecast Highlights:

A warm front cleared the area yesterday, setting up for a hotter and humid day west of NYC with cooler temperatures persisting east of NYC, while severe thunderstorms stayed to the north of the area. With the warm front having cleared most of the region, a heat wave will begin today, lasting through Saturday with temperatures in the low 90s until a cold front moves through on Sunday night into Monday, producing widespread thunderstorms followed by a return to cooler than average temperatures.

May 29, 2013: Hot, Humid Through Sunday

Forecast Highlights:

A warm front currently over the area will continue to move northeast, marking the beginning of a 5-day stretch of heat and humidity with scattered thunderstorms, possibly strong, likely this evening. The Thursday-Saturday time frame will contain widespread highs in the low 90s, with a cold front on Sunday into Monday producing widespread thunderstorms followed by a return to near-below average temperatures.

May 27, 2013: Rain Tomorrow/Weds, Then Hot

Forecast Highlights:

The storm that has been affecting the region for nearly a week has completely left the region, resulting in a mostly sunny and seasonable Memorial Day. The mild conditions were brief, however, as a minor change in the forecast scenario will bring another chilly and rainy day to the area for Tuesday, followed by a warm front passage on Wednesday morning which will mark the beginning of a 4-day heat surge, with temperatures in the upper 80s and low 90s.

May 26, 2013: Heat Wave Likely Late This Week

Forecast Highlights:

The storm that affected the region with unusually cold weather yesterday has mostly left, with warmer temperatures, more sunshine and highs in the mid to upper 60s across most of the area. In a significant reversal from the weekend cold, temperatures will end up well above average by the late week, with temperatures climbing near/over 90 degrees for the Thursday-Saturday time frame in what may be the first heat wave of the summer.

May 25, 2013: Weekend Cold, Late Week Heat

Forecast Highlights:

A cutoff low pressure is currently affecting the region with conditions more typical of the early spring season, with temperatures only in the 40s to low 50s with snow falling in high elevations of the Northeast. The system will clear the region in time for a sunny and seasonable Memorial Day, with the temperature trend flipping from much colder than average this weekend to warmer than average by the late week with over 90 degrees possible.

May 24, 2013: Cold Weekend, Then Gradual Warmup

Forecast Highlights:

A cold front crossed the area today, resulting in near average temperatures for eastern parts of the area and an unseasonably cold rain north and west of NYC with temperatures stuck in the upper 40s to low 50s. A cutoff low pressure will develop offshore and slowly track northeast, setting up for more rain on Saturday with much colder than average temperatures, eventually giving way to a warming trend with temperatures back above average by late next week.

May 23, 2013 Storm Updates

Below, occasional updates will be posted on the strong thunderstorms expected to affect the area today and tonight.

Links:
This morning's forecast discussion
Live twitter updates
5-Day Forecast

---

Blog Updates: (Regional maps from the National Weather Service)

7:10 PM: Since the last update, heavy thunderstorms continued to affect north central NJ into SE NY, while the rest of the area generally stayed dry. Radar estimates show totals of 1-2 inches of rain from Morris county into northern Bergen, Rockland and Westchester counties. As the latest radar shows, additional thunderstorms are slowly approaching from Pennsylvania; more rain and thunderstorms are expected tonight, especially north and west of NYC, with Long Island and southern CT likely to stay mostly dry through the early-mid overnight hours.

3:40 PM: Over the last hour, the focus in storms shifted east into the immediate NYC area, where radar estimates show 1/4 to locally 1/2 inch of rain. Storms are currently redeveloping over NE NJ and are expected to continue through the late afternoon hours, capable of localized downpours and areas of flash flooding. Additionally, storms in northeast PA are slowly shifting east into Sussex and Warren counties in NJ. These storms are weakening, although they are still capable of moderate to heavy rainfall rates.

2:35 PM: After the late morning round of storms, which produced up to 1/2 to 1 inch of rain in parts of northern NJ and SE NY, scattered storms are developing over Bergen, Hudson, Essex, Union counties in NJ and New York City. These storms are generally non-severe but are capable of producing heavy rainfall rates with low visibility. Scattered heavy storms continue over northern Westchester county into Danbury, CT, where areas of flash flooding are possible with the storms.

12:55 PM: There is an area of heavy thunderstorms currently covering northern NJ, extending into the NJ/NY border. The main line of storms is located on an axis from central Bergen to Rockland and northern Westchester counties. These storms are slowly tracking to the northeast. The storms are generally below severe levels, but are capable of producing heavy rain, locally up to 1/2 to 1 inch.

---

Twitter Updates:

May 23, 2013: Rainy Through Saturday, Dry Memorial Day

Forecast Highlights:

A slow moving cold front is currently approaching the region, with occasional showers and thunderstorms expected for today and Friday. A cutoff low will develop and slowly drift through the region, prolonging the shower activity through Saturday, or Sunday for eastern locations, replacing the warm and humid air mass from the last few days with well below average temperatures, struggling to approach 60 degrees for highs. This strong cool air mass will be relatively short lasting, however, with a warming trend towards the longer range.

May 22, 2013: Stormy Wed-Fri, Cooler Weekend

Forecast Highlights:

The heat and humidity return again today, with widespread highs in the 80s likely but with a risk of scattered thunderstorms, especially north of NYC. A cold front will move through on Thursday and Friday, producing widespread thunderstorms which could be strong, with cooler temperatures returning for Friday and  Memorial Day Weekend but with increasing uncertainty regarding the precipitation outlook.

May 20, 2013: Warmth, Humidity Continue

Forecast Highlights:

Much warmer temperatures were observed today with a warmer and more humid air mass in place, surging well into the 70s away from the coast. The warmth will continue on Tuesday and Wednesday with partly to mostly cloudy skies, a slight risk of thunderstorms, and highs in the 80s away from the coast. A cold front will produce widespread thunderstorms on Thursday into at least early Friday, likely clearing in time for Memorial Day Weekend.

May 19, 2013: Warmth, Humidity, Storms This Week

Forecast Highlights:

Widespread showers were observed across the area today with temperatures remaining below average, peaking in the upper 50s to low 60s across the area. With the area entering the warm sector, much warmer temperatures can be expected for the early-mid week, back into the 70s and possibly low 80s, along with a risk of scattered thunderstorms on most days, likely ending in time for a drier and cooler Memorial Day Weekend.

May 18, 2013: Cloudy, Stormy Week Ahead

Forecast Highlights:

An unexpected area of light-moderate rain affected most of the area this afternoon, with cooler than expected temperatures observed as a result. This is only the beginning of what will be a more active week, with partly to mostly cloudy skies and scattered showers and thunderstorms expected every day from Sunday through Friday, possibly severe towards the mid-late week, followed by potential clearing in time for Memorial Day Weekend.

May 18, 2013 Noon Update

4:00 PM: Rain Currently Affecting Area

Earlier this afternoon, a widespread area of light to moderate rain unexpectedly developed across most of the northern Mid Atlantic and spread into the area, resulting in cooler than expected temperatures for the afternoon hours, currently in the upper 50s to low 60s as opposed to the forecast for upper 60s to low 70s. These showers will continue through at least 6-8 PM, gradually ending from NW to SE, with less than 1/4 inch of rain expected.

The next update will be posted tonight, with more information regarding the upcoming stormy weather this week. The 5-Day Forecast page has been updated, as well as a new redesigned 5-Day Text Forecast page.

May 17, 2013: Warmer Temps, Storms Next Week

Forecast Highlights:

Sunshine and seasonable temperatures will continue on Saturday, but will be short lasting as clouds increase by Sunday with a risk of scattered showers. A brief surge of warmth is expected towards the middle of next week with 80 degrees possible again, but with a risk of thunderstorms expected as well, possibly strong or severe, followed by another cool down late in the week.

May 15, 2013: Warmer Ending To Week

Reminder: The blog will be in a limited updating schedule through Friday, May 17. Until then, updates will be posted every 2 days.

Forecast Highlights:

Scattered showers were observed early today ahead of a warm front currently moving through the region, ending a strong cool spell with morning temperatures in the 30s inland. A brief warmth surge is expected for the late week with highs warming up well into the 70s, but with persistence in the current pattern as the warmth struggles to settle in.

May 13, 2013: Widespread Frost Tonight

Reminder: The blog will be in a limited updating schedule through Friday, May 17. Until then, updates will be posted every 2 days.

Forecast Highlights:

An unseasonably cool air mass will remain in place tonight and tomorrow, with temperatures remaining moderately below average. A warmer air mass will return for the mid-late week, with some showers on Wednesday followed by highs back into the 70s by the late week into Saturday, but with a continued lack of sustained warmth as another storm approaches by early next week.

May 11, 2013: Cooler Temperatures Return

Note: The blog will be in a limited updating schedule through Friday, May 17. Until then, updates will be posted every 2 days.

Forecast Highlights:

A cold front is currently moving through the region after having produced widespread showers earlier this afternoon with a severe thunderstorm cell tracking over northeast NJ into NYC and western Long Island, producing heavy rain, strong wind gusts and small hail. A strong trough will move in behind the front with a short round of cooler than average temperatures, followed by another warm up by the late week.

May 11, 2013 Storm Updates

Note: Updates today will be limited and less frequent due to poor internet connection.

4:15 PM: The severe thunderstorm has cleared Manhattan and Queens, with reports of small hail and strong wind gusts in some of the locations it affected. The cell is currently weakening while over northern Queens, and will continue to move ENE, clipping northern Nassau county within the next 1/2 hour producing heavy rain and gusty winds. Another strong storm is over Brooklyn and is also expected to weaken while moving ENE into Queens and central Nassau county.

Drier conditions are expected behind these storms, with clearing skies behind the line although scattered showers can't be ruled out through the evening.

3:40 PM: A squall line is approaching NYC. A severe thunderstorm is located near Essex/Union counties and is moving ENE, and will affect Hudson, south Bergen in NJ and New York City/south Westchester within the next 15-45 minutes. This storm is capable of producing small hail, strong wind gusts, and heavy rain up to 3/4 inch/hour.

Another severe storm is developing near northern Middlesex county, and will move east into Staten Island and southern NYC, capable of producing heavy rain and gusty winds.

May 10, 2013: Rain Returns For Saturday

Forecast Highlights:

Temperatures surged well into the 70s and low 80s across most of the area today, but this surge of warmth will only be brief as a cold front approaches on Saturday, producing rain and thunderstorms, some of which may be strong. Behind this cold front a brief but strong cool surge is expected, with temperatures dropping into the 30s inland with frost possible followed by a late week warmup.

May 9, 2013: Stormy Saturday, Then Cooler

Forecast Highlights:

After another round of rain earlier today, the upper level low is moving out of the region, with more sunshine and much warmer temperatures expected for Friday. Another storm will move through overnight into Saturday producing additional rain and thunderstorms, followed by drier conditions for Sunday into early next week but with colder temperatures returning as well, falling into the 30s inland.

May 9, 2013 Storm Updates

3:45 PM: Storms Moving Out

Widespread showers and thunderstorms affected Long Island and southern CT over the last few hours, with radar estimates showing most of the LI/CT region aside from central Long Island with up to 1/4", locally higher. Since then, these showers have mostly moved out of the area, and are currently focused over central-northern CT. With the upper level low nearby, mostly cloudy skies are expected for the rest of the day with a risk of isolated showers but no widespread moderate-heavy rain. The next round of rain after today is expected on Saturday night into Sunday with an incoming cold front separate from the current ULL.


11:35 AM: Storms Continue

The batch of rain that was previously located over NE NJ has since moved north into SE NY, producing moderate to locally heavy rain. Radar estimates show a band of 1/2 to 1 inch of rain from Newark to western Bergen county in NJ and Rockland county in NY, with the highest total so far in Newark, NJ with 1.40" of rain so far. A localized strong thunderstorm is located over Queens, producing locally heavy rain with radar estimates also showing a small area of near 1" totals.

Additional thunderstorms are forming and expanding off the coast, tracking north into Long Island. A developing batch of moderate to heavy thunderstorms will move onshore into Nassau and western Suffolk counties shortly, producing at least 1/4" to 1/2" with locally higher amounts. Another strong thunderstorm is currently south of central Long Island and tracking NNE, which should affect the eastern half of Suffolk county within the next 30-60 minutes.


9:45 AM: More Rain Near NJ, NYC

As mentioned last night, an area of showers, locally heavy, developed near eastern NJ and is currently slowly moving NNE, affecting NYC and especially northeast NJ with moderate to heavy rain. The heaviest rain from this batch of rain is between the I-95 and Garden State Parkway corridors with a narrow strip of 1/2" to 1 inch, while other locations have generally recorded up to 1/4 inch so far. This round of rain will continue for at least the next 1-2 hours, tracking north into SE NY while clipping western parts of LI and CT. At least 1/4" to 1/2", locally up to/slightly over 1" in isolated spots, is expected across north central/NE NJ and SE NY, with NYC on the eastern end of this area.

Meanwhile, another batch of rain is located near eastern Long Island and SE CT, also tracking north. This area of rain is weaker than that near NJ, but is still producing light to moderate rain with amounts generally up to 1/4", locally higher. A break in the rain is likely near NYC and NJ later today as the upper level low moves overhead, with scattered showers/storms to continue in LI/CT at least through the early afternoon hours.

May 8, 2013: More Showers Through Saturday

Forecast Highlights:

An upper level low continues to slowly track northeast through the region, having produced heavy rain and thunder in parts of the area this morning with as much as 3 inches in Central Park. The ULL will continue to produce showers on Thursday, with another storm system moving in for Friday and Saturday resulting in a brief surge of warmth and additional showers, followed by a strong cool down early next week with the possibility for interior frost.

May 8, 2013 Storm Updates

2:35 PM: Heavy Rain Moving North

Over the last 2 hours, a line of heavy thunderstorms spreading from LI into northern NJ tracked northwest, spreading into the rest of northern NJ and SE NY, while a narrow line of heavy storms formed in central/eastern Long Island and moved north into Connecticut. As the latest radar shows, most of the storms are currently to the north of the area. The widespread heavy rain is mainly over for today, although additional scattered showers and thunderstorms are still possible later this afternoon and evening.

Central Park has recorded 3.02 inch of rain so far, a little over 1 inch in just an hour. This storm total is about 72% of the average May rainfall (4.19"), and cut this year's precipitation deficit by over a half, which as of yesterday was over 5 inches below average. The highest rain totals came out of NYC into eastern NE NJ with additional reports of 2-3 inches of rain, while the rest of northern NJ and SE NY have observed at least 1/2 to 1.5 inch of rain. LI and CT are on the drier side, with at least 1/4 to 1/2 inch so far, locally higher in some spots. A sharp rain gradient was observed east of NYC; while JFK had 1.54" of rain, Farmingdale, NY (Nassau) only recorded 0.34". Some additional rain totals so far include 2.28" in LaGuardia airport and 2.14" in Teterboro, NJ.


12:50 PM: Heavy T-Storms Near NYC

Since the last update, another line of heavy thunderstorms formed, stretching from Long Island to New Jersey along the I-78 corridor. The NJ segment of the line is training in place through Morris county, expected to produce at least 1/2 to 1 inch over the next 2 hours. The eastern segment of the line stretches from NW Suffolk county to northern Nassau, northern parts of NYC into the Bronx and is tracking NW, towards far NE NJ and SE NY. This line is capable of producing rainfall up to 1/2 inch in an hour, which will further increase already significant rain totals near NYC.

Once this line of rain moves out of NYC, scattered showers and thunderstorms are still expected later in the day but with the focus of the rain shifting north into LI, CT and NY state. Scattered storms are expected again on Thursday with the upper level low overhead but without the heavy rain and flash flooding that was observed today. More information on the outlook for the rest of the week and weekend will be posted tonight, including a brief surge of heat on Friday and possible thunderstorms overnight and on Saturday.


10:45 AM: Showers, Thunderstorms Continue

Since the last update, as the latest regional radar from the NWS shows to the left, the heavy rain gradually ended over northern NJ and NYC, weakening as it shifted north into SE NY and Long Island but still producing locally heavy showers and thunderstorms. The heaviest rain fell between 8-9am, with Central Park recording 1.06" and Teterboro, NJ recording 0.83" in that 1-hour period alone. This brings the storm total so far to 2.39" in Central Park.

Current radar estimates show a narrow band of 1.5"+ in Brooklyn and Manhattan in NYC, and Hudson, south Bergen and Passaic counties in NJ, and isolated areas of 2"+ in Brooklyn and Manhattan. Otherwise, rain totals in northern NJ and SE NY are generally between 1/2 and 1 inch, with most of Long Island and CT below 1/4" so far but expected to increase as showers continue throughout the day.


8:45 AM: Heavy Rain Over NYC

Over the last few hours, a slow moving heavy rain band with some thunder stretched from NYC into NE NJ, producing heavy rain rates with Central Park at 1.28 inch of rain so far, 0.34" in the last hour. Heavy rain will continue over the next few hours, gradually tapering off to a few showers from SE to NW, across NYC, northern NJ and SE NY, with areas of flash flooding possible and totals locally up to 1-1.5 inch. Throughout the day, light to moderate rain, locally heavy, will shift north towards Long Island and Connecticut, with up to 1/2 inch expected, locally higher up to 1 inch.

May 7, 2013: Rain Tomorrow, Weekend Showers

Forecast Highlights:

The stretch of dry conditions will come to an end tonight as an upper level low moves through, producing rain, locally heavy, across the area on Wednesday with scattered showers expected to continue on Thursday, Friday and Saturday. Temperatures will initially remain seasonably mild, leaning on the warm side on Friday, but cooling down early next week with the possibility for inland frost.

May 6, 2013: Rain Returns On Wednesday

Forecast Highlights:

The recent stretch of dry conditions without rain will come to an end as a low pressure tracks up the coast, producing widespread showers across the region especially on Wednesday. Generally seasonable temperatures will continue through the weekend along with scattered showers, with drier conditions returning by Sunday and early-mid next week but along with a strong cool air mass.

May 5, 2013: Rain, Possible Cool Temps To Return

Forecast Highlights:

After a week long stretch of mostly seasonable temperatures and a persistent high pressure in place, the blocking is gradually breaking down, which will allow for rain and clouds to return and persist for the second half of the week into next weekend, before a possible late season cool down early next week.

May 3, 2013: Mild Weekend; Rain Uncertainty Next Week

Forecast Highlights:

After a weak back door cold front moved through the area last night, temperatures today were slightly cooler than those of yesterday, especially inland. Temperatures will remain mostly seasonable with mostly sunny skies through the weekend into early next week, but with uncertainty regarding the next storm towards mid-late next week and how much rain it produces.

May 2, 2013: Brief Cool Down Friday, Then Warmer

Forecast Highlights:

After a relatively mild day, with northern parts of the area reaching the mid to upper 70s, a back door cold front is currently moving through the region, resulting in a brief increase in cloud cover overnight followed by slightly cooler temperatures for Friday. Warmer temperatures are expected for the weekend into early next week with mostly sunny skies continuing, with a storm expected to track nearby towards the middle of next week but with uncertainty regarding how much, if any rain falls.

May 1, 2013: Mild, Sunny Weekend Ahead

Forecast Highlights:

With a high pressure staying in place, generally seasonable conditions are expected to continue through the rest of the week into the weekend and early next week, with a sunny and mild weekend expected across the area. A storm will approach the region by mid next week but with uncertainty regarding how much rain will fall, especially given the recent increasingly dry conditions.