Thursday, February 28, 2013

Feb 28, 2013 Brief Update


Note: The next full discussion, including an updated 5-day forecast, will be posted starting on Friday.


Tonight - Weekend: Slowly Cooling Down

There are no major changes to the forecast from yesterday's update. Temperatures will gradually cool down over the next few days, dropping on Friday into the low to mid 40s inland and mid to upper 40s for the rest of the area, and into the low to mid 40s for Saturday through early-mid next week, generally slightly cooler than average. Partly to mostly cloudy skies are expected to continue, with a risk of isolated showers on Friday.


Next Week Update:

The latest model guidance continues to signal for a storm potential around next Wednesday; currently, the model guidance keeps this south of the area, some models well to the south, although this is still at least 6-7 days away and additional changes are expected with the models. While most show this south of the area, it is possible that the models trend north with the storm affecting the region including the area, in which case widespread rain and snow accumulations would take place. More information on this will be posted over the next few days as details become clearer.

Wednesday, February 27, 2013

Feb 27, 2013: Clouds, Showers Persist Through Friday


Note: Updates tonight and tomorrow will be brief. The next full discussion will be posted on Friday.


Tonight - Weekend: Gradually Warming Up

As the upper level low gradually continues to move away from the region, partly to mostly cloudy skies and scattered showers will persist through Thursday and Friday, with highs warmer than average, peaking in the mid 40s to low 50s on Thursday and low-mid 40s inland, mid-upper 40s for the rest of the area on Friday. Highs will gradually trend slightly cooler over the weekend as skies clear and a strong trough moves through the region, with highs on Sunday down into the upper 30s-low 40s inland and low-mid 40s for the rest of the area, generally near to slightly below average.


Next Week Overview:

Similar temperatures to those of the weekend will continue into the early-mid week, possibly slightly cooler with overnight lows generally in the 20s for most of the area. The next potential for a storm is towards next Tuesday-Wednesday; currently, most models keep this storm south of the area aside from the ECMWF, although this is still nearly a week away with additional changes expected with the model guidance, and the potential remains for a storm to affect the region, possibly including the area, in this time frame. More information will be posted as details become clearer.

Tuesday, February 26, 2013

Feb 26, 2013 Evening Update


Note: Tonight's update was delayed due to technical difficulties. The next full discussion will be posted on Friday, with brief updates on Wednesday and Thursday nights.

Evening Storm Update: Precipitation developed across the area this evening; this was mostly in the form of rain in NE  NJ, NYC and Long Island, with snow/sleet/ice in NW NJ, SE NY and parts of southern CT. Most of the area will continue to see rain tonight while interior areas gradually change over to rain, with up to 1-2 inches of snow/sleet expected. Rain is expected to end on Wednesday morning from south to north, with highs in the low to mid 40s in southern CT, mid to upper 40s in SE NY and Long Island, and upper 40s to possibly low 50s in NE NJ and NYC.

Highs will remain warmer than average for the rest of the week, peaking in the mid 40s to low 50s on Thursday and the low-upper 40s on Friday and Saturday with partly to mostly cloudy skies and scattered showers, clearing by the weekend. A full forecast update will be posted tomorrow.

Sunday, February 24, 2013

Feb 24, 2013: Stormy Tuesday Night, Wednesday


Forecast Highlights:

The system that has affected the region over the last two days is currently moving out, with scattered snow showers observed north/east of NYC this evening. Dry conditions will briefly return for Monday with highs in the 40s, followed by another storm on Tuesday night into early Wednesday expected to produce heavy rain, wind, and snow/ice for interior locations. Behind this storm, seasonable to slightly cooler than average temperatures will continue through the weekend.


Click here for the latest 5-day forecast >>

Feb 23, 2013: Tuesday Storm To Produce Rain, Snow, Wind


Forecast Highlights:

A weak storm continues to affect the region today with light rain and some snow for interior locations. Mainly to mostly cloudy skies will continue tonight and tomorrow with light rain showers expected to continue especially in Long Island and CT tomorrow, accompanied by warmer temperatures in the 40s for Sunday and Monday. The next storm will then affect the area on Tuesday night into early Wednesday, producing moderate-heavy rain, strong wind gusts, and potentially snow/sleet for interior areas.


Saturday, February 23, 2013

Feb 23, 2013 Noon Update


12:40 PM: Last night's update noted the storm was expected to be weaker than previously thought, with lower rain totals generally up to 1/4 or 1/2 inch. Based on current observations, however, even this forecast may be a bit too high with hardly any precipitation currently over the region aside from scattered showers over the area. Scattered showers are expected to continue through tonight with a period of steadier light rain in the late afternoon and evening hours, especially in NYC and further east/northeast, otherwise rain totals are generally expected to stay under 1/4 inch west of NYC, with 1/4 to 1/2 inch in Long Island and southern CT. Northernmost parts of the area are expected to see little to no snow accumulations, locally up to 1/2 inch. From NYC and further west, rain is expected to end early tonight aside from scattered overnight showers with clearing skies by Sunday morning, with more cloud cover and scattered showers persisting on Sunday east of NYC.

Friday, February 22, 2013

Feb 22, 2013: Rain For Tomorrow, Tuesday


Forecast Highlights:

Today brought warmer temperatures to the area as the cold air mass that was present over the last few days weakened, with highs peaking in the mid to upper 30s. The next storm will affect the area on Saturday into Saturday night, with light to moderate rain expected along with some snow inland. Warmer temperatures are expected behind the storm, although dry conditions won't last for long as another storm affects the area next Tuesday.


Thursday, February 21, 2013

Feb 21, 2013: Stormy Pattern Continues


Forecast Highlights:

Cold and windy conditions continued today across the area, although the overnight lows ended up warmer than expected with increased cloud cover last night, with temperatures failing to drop much, in some cases not dropping at all. Warmer temperatures are expected to return for Friday into the weekend as the next storm approaches, producing moderate rain across the area and some snow for interior locations. The pattern only becomes more active afterwards, however, with another storm on Tues-Weds followed by a strong trough to start early March.


Wednesday, February 20, 2013

Feb 20, 2013: Rain, Some Snow For Weekend


Forecast Highlights:

Cold and windy conditions returned into the region today behind the cold front that moved through the area yesterday, producing moderate rain, with similar conditions expected to continue into tonight and tomorrow. Temperatures will warm up ahead of the next storm on Saturday, expected to be a moderate rain producer for most of the area and a potential snowstorm inland, followed by another storm towards the middle of next week.


Tuesday, February 19, 2013

Feb 19, 2013: Next Storm Expected This Weekend


Forecast Highlights:

A weak storm affected the area today, producing rain for most with totals generally up to 1/4 inch. Interior western parts of the area, however, started out with a period of moderate snow with minor accumulations, especially in the higher elevations. Temperatures briefly warmed into the upper 30s to mid 40s, although a cold air mass will return for Wednesday and Thursday with windy conditions expected again. The stormier pattern is expected to continue afterwards with a storm for the weekend and another towards February 26-27.

Feb 19, 2013 Storm Updates


A few updates will be posted regarding today's storm. The next forecast discussion will be posted tonight focusing on the Friday night-weekend storm.



12:30 PM: Over the last 1/2 hour, precipitation spread into the western half of the area, with reports of moderate to locally heavy snow over western and parts of central New Jersey. The rain/snow line is not expected to advance much more southeast, with the immediate NYC area, Long Island and southern CT still expected to end up with rain. For interior western locations, a changeover to rain is likely later on, although some locations may receive a coating to locally 1/2 inch of snow until then, especially the higher elevations further west.

11:50 AM: The latest radar loop posted to the left shows a relatively narrow band of moderate precipitation over eastern Pennsylvania into Maryland and Virginia, moving northeast towards the area. Snow has been reported across eastern Pennsylvania into parts of Maryland, although these areas received precipitation earlier in the morning, falling as snow while preventing surface temperatures from significantly warming up.

In the NYC area, however, the onset of precipitation was delayed enough compared to Pennsylvania to allow for surface temperatures to quickly warm up into the upper 30s-low 40s inland and the mid 40s for the rest of the area. With a continued southerly flow and warmer temperatures at the surface compared to locations further west, precipitation is expected to fall as rain across the area, although western-possibly central NJ and interior SE NY are likely to start out with some snow, especially with a small pocket of sub-freezing 925mb temperatures approaching from Pennsylvania. Showers will continue through the afternoon and early evening hours before ending, perhaps ending as snow for interior areas, with at least 1/4 inch of rain expected.

Monday, February 18, 2013

Feb 18, 2013: Rain Tomorrow, Then Cold/Windy


Forecast Highlights:

Cold temperatures were observed this morning, dropping into the 10s for lows with wind chills approaching zero degrees, with temperatures so far today having warmed up into the upper 20s and 30s with continued breezy conditions. A brief warm up is expected with a minor rain event on Tuesday, followed by another round of cold and windy conditions until the next storm affects the region on Friday night into Saturday.


Sunday, February 17, 2013

Feb 17, 2013: Cold And Windy Tonight, This Week


Forecast Highlights:

After a coastal storm intensified off the coast, bringing 1 to 3 inches of snow across eastern parts of Long Island and eastern CT, left the region heading into Atlantic Canada, windy conditions developed today with colder temperatures, generally in the upper 20s to mid 30s. Windy conditions will continue tonight and on Monday as temperatures drop into the 10s, with wind chills near to below zero expected; after a brief warm up on Monday with rain, cold and windy conditions will return for Tuesday and Wednesday, followed by a rain/snow event on Friday.


Feb 16, 2013 Brief Update


Short Term Update: A band of light to moderate snow is currently affecting central-eastern Long Island and Connecticut, with early accumulation reports as of 12 AM generally under an inch. The band of snow will continue to very slowly shift east overnight as a coastal low pressure, currently east of the Virginia coast, continues to quickly intensify while moving northeast away from the region. Accumulations of 1 to 4 inches are expected in central to eastern Long Island and central-eastern CT; localized accumulations over 4 inches, especially further east, cannot be ruled out. The snow is expected to end by the morning hours.

The latest forecast for the rest of the week can be found in today's afternoon update. The next forecast discussion will be posted on Sunday.

Saturday, February 16, 2013

Feb 16, 2013 Noon Update


Due to a busy schedule, I was unable to post an update last night. Another update will be posted tonight regarding the storm, with fully daily discussions to be resumed on Sunday.



Tonight's Storm: Light Snow East of NYC

Last night, a narrow band of heavy snow affected the western half of the area, especially towards western NJ and interior SE NY, where accumulations up to 2 inches have been reported with locally higher totals over 2 inches. As the latest radar shows, a narrow yet long band of light to moderate precipitation stretches along the coastal areas, extending further south into the Southeastern states, and is very slowly shifting to the east with a slow moving cold front just off the coast. This frontal boundary will continue to slowly shift to the east as a stronger coastal low pressure develops off the southeastern US coast, quickly intensifying as it tracks northeast towards Atlantic Canada.

This storm, after several days of uncertainty with a variety of solutions painted on the model guidance, will end up staying east of NYC, with mainly cloudy skies and scattered flurries expected from NYC and further west. To the east of NYC, however, is where more snow is expected to fall. The short range model guidance is split regarding how far west snow from the coastal low spreads; most of the models are further east, scraping the coast with light snow as the heaviest snow develops further offshore, although the GFS remains the westernmost model with more significant accumulations in the eastern half of Long Island and Connecticut and a major snowstorm for southeastern New England. The GFS solution is currently not supported by the main model guidance, but only minor changes in the setup would bring snow from the coastal low slightly further west with more impact in Long Island and Connecticut.

Latest Forecast: The forecast for tonight is for light snow to develop in Long Island and southern CT late this evening, with occasional light to locally moderate snow in the overnight hours, ending early on Sunday morning. Accumulations are expected to end up between 1 and 4 inches, with the highest accumulations further east towards eastern LI and SE CT. The development of this storm will continue to be monitored, however, for the possibility of minor changes in the setup which would slightly change the forecast snow totals.


Forecast Update: Partly sunny skies are expected for Sunday but with strong winds as the coastal low intensifies well east of the area, with NW winds at 25-35 mph and gusts up to or over 40 mph. High temperatures will reach the mid to upper 20s inland and upper 20s for the rest of the area. Cold overnight lows are expected with continued windy conditions, dropping into the low to mid 10s inland and mid to upper 10s for the rest of the area. Highs will return into the 40s on Tuesday with a light rain event, followed by the return of colder temperatures with highs in the low to mid 30s inland and mid to upper 30s elsewhere along with a storm on Friday, which currently appears likely to produce snow but with the forecast still subject to change. More information on the extended forecast will be posted on Sunday.

Friday, February 15, 2013

Feb 15, 2013 Noon Update


Weekend Storm Update: The model guidance continues to show a storm affecting parts of the region, but as of the most recent blog update on Thursday morning, there was some uncertainty regarding how this plays out, whether it's a light to moderate snowstorm for the area with higher totals towards Connecticut, or a minor snow event with totals under 2-3 inches. The model guidance has been split between these solutions, but are converging on an agreement with the latter scenario, in which the area sees light rain/snow changing to snow tonight into Saturday morning, with minor accumulations generally up to 1-2 inches possible.

Uncertainty has been focused on a stronger coastal low pressure that develops off the southeastern US coast on Saturday, tracking northeast parallel to the coast overnight into Sunday while quickly intensifying. Some models earlier showed this close enough to the coast to result in a major snowstorm for the area into New England, but have since backed to the east, with the most impacts from this coastal low likely towards Long Island and New England. This part of the forecast can still slightly change, although at this time the coastal low is mostly expected to stay east of the area, with additional light snow on Saturday night for Long Island and southern Connecticut, especially further east, with additional light to possibly moderate accumulations. At this time, accumulations are expected to remain under 4 inches in Long Island and CT, although should the storm end up slightly further west, accumulations over 4 inches may be possible for eastern Long Island and SE CT. Dry conditions are expected for Sunday as the storm reaches its peak near Atlantic Canada, with much colder temperatures as highs only rise into the mid to upper 20s.

A more detailed forecast will be posted later tonight, along with an update on the potentially stormy pattern coming up for the next 1-2 weeks.

Thursday, February 14, 2013

Feb 14, 2013: Snow Saturday, Then Cold


Forecast Highlights:

Following last night's storm, with some locations barely observing flurries and others picking up over 2 inches of snow, a brief warm up is on the way for today and tomorrow, with highs reaching the 40s to low 50s across the area. A storm is expected to produce snow on Saturday, followed by a short lived yet strong surge of cold air for the weekend into the early week. Click below for new information regarding the Saturday snow potential.


Wednesday, February 13, 2013

Feb 13, 2013: Snow Tonight, Then Mild Friday


11 PM Update: Parts of the post regarding Friday night-Sat have been revised.

Forecast Highlights:

The first snowstorm to affect the region since the blizzard last Friday will produce some snow and rain across the area tonight, with totals generally up to 2 inches, locally higher. Mild temperatures will make a brief return, with highs reaching the low 50s across parts of the area on Friday. A strong surge of cold air will follow for the weekend, but will quickly give way to another storm early next week with rain and possibly snow.



Tuesday, February 12, 2013

Feb 12, 2013: Some Snow Weds Night, Mild Friday


Forecast Highlights:

Temperatures close to average continued across the region today following yesterday morning's rain event, with highs peaking in the low to mid 40s across the area. A storm is expected to affect the area with some snow on Wednesday night, followed by warmer temperatures briefly returning on Friday, reaching the upper 40s to low 50s in NYC. A colder weekend is expected with the potential for a storm to affect the region.


Monday, February 11, 2013

Feb 11, 2013: Two Storms Coming Up


Forecast Highlights:

After moderate rain fell this morning with freezing rain west and north of NYC, the storm moved out faster than expected, with widespread fog and temperatures in the upper 30s to mid 40s currently observed across the area. An active pattern continues for the region going into the medium range; despite just having gone through a blizzard on Friday, two more storms are coming up; a moderate snowstorm for Wednesday night, and the potential for another storm next weekend.


Sunday, February 10, 2013

Feb 10, 2013: Ice/Rain Monday, Thurs Storm Possible


Forecast Highlights:

Mainly sunny skies were observed today aiding in the clean-up after the blizzard in Long Island and Connecticut, with high temperatures in the low to mid 30s. Stormy conditions will make a brief return on Monday, however, with light ice accumulations for interior parts of the area in the morning followed by moderate rain for the rest of the area as temperatures rise into the 40s. Seasonable temperatures will continue for the rest of the week with storm potentials on Wednesday night and a potentially larger storm for the weekend.


Saturday, February 9, 2013

Feb 9, 2013 Forecast Update


Forecast Update:

Following last night's blizzard, which dumped significant to excessive amounts of snow across most of CT and parts of Long Island with lower amounts to the west, skies have cleared with a high pressure moving through tonight and tomorrow. Cold temperatures are expected tonight, dropping into the mid to upper 0s for NW NJ and interior SE NY, upper 0s to mid 10s across northern NJ, southern CT and most of Long Island, with mid to upper 10s closer to NYC. Mainly sunny skies are expected for Sunday with highs in the low to mid 30s.

The next storm to affect the region will be on Monday. A low pressure tracking through the Midwest tonight, where blizzard warnings are in effect, will track towards the Great Lakes and southern Canada on Monday, bringing a warm front through the region on Monday morning. Enough cold will be left over for interior parts of the area to start out with light freezing rain. Ice accumulations are expected to mostly end up under 0.10 inch, although even light freezing rain can cause hazardous conditions. Interior areas will change over to rain by the mid morning hours, with temperatures rising into the low to mid 40s across most of the area for highs, ending up coolest towards interior areas with highs near or a little over 40 degrees. Moderate rain is expected across the entire area through the mid afternoon hours, with drier conditions likely to return by the evening. Rain totals are currently expected to end up between 1/4 and 1/2 inch.

The next storm to affect the region will be on Wednesday into early Thursday; this storm is not expected to be nearly as strong as today's storm, but will still be capable of producing at least a light to moderate snowstorm in parts of the region. The main question at this time is how far north the storm ends up; some models keep the storm well south of the area, while the GFS is currently siding with a northern outcome with a snowstorm in parts of the central Mid Atlantic with the NYC area in the northern end of the storm. At this time, the forecast is for most of, if not all of the snow from this storm staying south of the area; keeping in mind this is still several days away, however, additional changes with the models are expected, and it is still possible that the storm ends up closer to the area with some more impact. Stay tuned for more information on this potential storm over the next few days.

Feb 8-9, 2013 Blizzard Summary


February 8-9, 2013 Blizzard Summary

The first major blizzard since January 2011 affected the area on February 8-9, 2013, as two low pressures, one in the interior and another off the coast, phased over the region. This combination brought heavy snowfall for the area, with the worst of the storm focused over Long Island into southern New England where blizzard conditions were observed with snow totals over 18-24 inches. In the area, 8 to 16 inches of snow fell west of NYC, with 16 to 32 inches, locally as high as 40 inches, in Long Island and southern CT.


Feb 9, 2013 Morning Update - Storm Ends


Note: The Storm Updates page is in the process of being redesigned, and I am attempting to get this done as quickly as possible. In the meantime, this relatively brief summary of today's blizzard has been posted. Once the page's updates are completed, which I hope to get done within this week, more detailed summaries and overviews of Hurricane Sandy, the 11/7 storm, and this blizzard will be posted, with more summaries of other past storms to be posted by the originally planned time frame of completion in March or April.



10:45 AM: Blizzard Ends Across Area

As of early this morning, the storm has ended across most of the area except for parts of Connecticut and Long Island, where light snow continues to fall. For most of the area, this was the most significant storm since either October 29, 2011 or January 26-27, 2011, both of which dumped over a foot of snow in parts of the area. Despite relatively moderate snow totals from NYC and further west, the worst of the storm took place over Connecticut, Rhode Island and Massachusetts, where widespread 20-30 inch totals were reported, with as much as 38 inches in isolated locations.

Regional radar image from 5:18 PM,  from the National Weather Service

Snow initially developed in the early to mid morning hours across the area; this was mostly snow in northern NJ and southern CT, but a wintry mix of rain, snow and sleet in NYC, Long Island, and most of New Jersey south of I-80. As the low pressure continued to intensify and track up the coast, snow intensified across the area, with heavy bands moving onshore into Suffolk county, where very heavy snow rates developed in some areas with sleet in others. The track of the coastal low pressure was a little too far east for most of the area to receive heavy snow, and the precipitation shield shifted far east enough by the afternoon so that aside from far northeastern NJ, almost the entire state of NJ was dry by the evening.

Regional radar image from 11:38 PM,  from the National Weather Service

Since yesterday evening, heavy snow continued to fall across portions of Long Island and Connecticut with a heavy band of snow stalled overhead, especially through central Connecticut into parts of Suffolk county, Long Island, with snow rates up to, or in some cases over, 3 inches per hour. After the dry slot that initially covered most of New Jersey around 7 PM, heavy snow quickly redeveloped across the state, with moderate to heavy snow continuing through the rest of the evening, while heavy snow spread across the rest of Connecticut into Long Island, including parts of coastal Long Island that had seen primarily sleet until that point. Towards 1-3 AM, a narrow but intense band of snow moved southeast across the area, from northwestern NJ towards the immediate NYC area; while this band was quick moving, snow rates up to 3-4 inches per hour were reported, dropping a quick inch of snow within only 15-20 minutes. The snow gradually ended afterwards through the rest of the overnight and morning hours as the storm shifted into New England.


Storm Totals: The worst of the storm took place in Connecticut, where this storm is likely to end up as one of the biggest snowstorms on record. Snow totals over 16-18 inches have been recorded across all of southern and central Connecticut, with up to 30 inches in Bridgeport, CT. The most significant totals were in New Haven county, where widespread 30+ inches have been observed under the stationary snow bands throughout the evening and early overnight hours. The highest report to come out of the area so far is 40 inches in Hamden, CT. Totals were more variable across Long Island; locations in the southern and western parts of the island, which had mixing with sleet lowering snow totals, ended up with at least 8 to 16 inches of snow. Towards NE Nassau and northern Suffolk counties, where the heaviest snow fell last night in the island, totals of at least 16 to 30 inches have been recorded, with a maximum of 30.9 inches in Upton, NY.

From NYC and further west, snow totals were generally on the moderate side, relatively moderate compared to other parts of the region. Snow totals of about 8 to 15 inches have been reported across northern New Jersey, NYC, and interior SE NY (Rockland/Orange counties); Central Park, which has seen little snow since the November snowstorm, reported a total of 11.4 inches. Westchester county, on the edge of the heavy snow bands in Connecticut, recorded snow totals between 10 and 23 inches of snow. A more detailed storm summary will be posted late this week or next weekend, along with summaries for Sandy and the 11/7 nor'easter, which will also include a snow map for total reports.

Northern NJ, interior SE NY, NYC: 8-15 inches
Westchester county, NY: 10-23 inches
Long Island (NE Nassau and north Suffolk counties): 16-30 inches
Long Island (everywhere else): 8-16 inches
Southern Connecticut: 16-38 inches


Forecast Update: From current indications, there are more storm possibilities coming up within the next two weeks. After a warmer storm with some rain on Monday with highs returning into the 40s briefly, which will accelerate the melting of snow across the area, temperatures will return into the 30s for highs next week, with more storm potentials along the way; the first potential is towards Wednesday and Thursday, and is more uncertain at this time as some of the model guidance hints at another storm while others keep it well to the south. There is no high confidence on the storm getting far north enough to affect the area, and if it does so, it will not be nearly as significant as last night's storm, but the possibility is there for some impacts from this storm. Another potential for a storm exists towards February 16-17; both of these potentials will be discussed in more details with the next forecast update tonight or Sunday morning.

Friday, February 8, 2013

Feb 8-9, 2013 Storm Updates


Storm updates will be posted below on the major snow and blizzard event currently affecting the region. Live storm updates will be posted on Twitter, with occasional detailed updates and any revisions to the forecast in the bottom of this post. Last night's forecast discussion for the storm can be found here.



Live storm updates will be posted on Twitter occasionally throughout the day.

Twitter updates from February 8-9, 2013 are archived in the NYC Area Weather twitter page.





Blog Updates:


2:08 AM Update: The band of snow is located over western Bergen into Essex counties, and is moving southeast. Snow rates over 3 inches per hour have been reported with very low visibility; the band will last for less than an hour, which should still add totals of at least 1 or more inch for locations under this band. This band marks the end of the snow; behind it, snow will gradually taper off.



1:35 AM Update: Narrow but heavy snow band is currently located over western Passaic and SE Orange counties, extending down to eastern Morris county and Philadelphia. This band is moving southeast, and will affect NE NJ and NYC within the next 1/2 to 3/4 hour. Very heavy snow rates can be expected over 2 inches per hour along with lowered visibility.


1:15 AM: Over the last 30 minutes, additional developments have taken place. The bands over Connecticut drifted west, now over Bridgeport, CT, and have actually intensified, with a 35+dbz band of heavy snow nearly stalled overhead, connecting into western Suffolk county. The snow will weaken within a few hours, but with the bands stalled over the same locations for the last few hours, widespread totals above 24 inches are expected in this axis.

Another update to make note of is the thin line of heavy snow bands over NW NJ. A heavy snow band is currently located near Orange county, NY and is moving southeast. This band may weaken as it approaches NYC but is likely to result in heavier snow rates over Passaic and western Bergen counties over the next 1/2 to 1 hour. Snow will gradually begin to end behind this line.

Unless unexpected changes occur, this will be the last storm update for tonight. A brief summary update will be posted in the morning, with the next forecast discussion to be posted tomorrow night or on Sunday morning regarding the upcoming pattern through the rest of the month with the possibility for more snow events.



12:40 AM: As of 12 AM, the low pressure was located slightly northeast of the previous 10 PM location, south/SSE of Cape Cod and east of central NJ. The minimum pressure is just under 980 mb with the low slowly moving to the northeast.

Moderate to locally heavy snow continues over northern NJ and SE NY as the back end of the storm approaches northwestern NJ and interior SE NY in the form of heavy snow bands drifting SSE. These bands will result in temporary heavy snow rates, lower visibility and stronger wind gusts. West of NYC, the storm is expected to end towards 4-7 AM, with final snow totals between 9 and 16 inches of snow, locally higher in some spots and lower in others.

The highlight of the storm is over Connecticut into portions of Suffolk county in Long Island, where heavy snow continues to fall with the highest totals in the area expected. A heavy band of snow remains stalled over the New Haven-Bridgeport to Hartford, CT corridor, where totals as high as 24-34 inches are expected. Elsewhere, moderate to heavy snow continues to fall, with snow continuing through the morning hours before ending.


11:25 PM: As of 10 PM, the low pressure was located south of Cape Cod and east of central New Jersey. Minimum pressure has been steady at approximately 982 mb for the last 2 hours. The low continues to track to the northeast, although it has significantly slowed down.

After the extreme heavy snow bands weakened in Long Island and Connecticut, the heavy snow bands extended west through Long Island, and are currently stalled over New York City and western Long Island, clipping portions of northeastern NJ. These bands are producing heavy snow with low visibilities and snow rates of up to 1-2 inches per hour. Moderate to locally heavy snow otherwise continues across northern NJ and SE NY as well as southeastern CT.

The heaviest snow is currently located near the New Haven-Bridgeport to Hartford corridor in Connecticut with a band of 30-35dbz snow stalled. These locations will end up with the highest snow totals in the area when adding the earlier very heavy snow, with totals as high as 24-34 inches in this axis. Otherwise, most of southern Connecticut is expected to end up with 16 to 26 inches of snow, with totals as usual locally higher or lower. Suffolk county in Long Island, affected by heavy snow earlier today, is expected to end up with similar totals to the rest of southern CT, with the rest of Long Island generally from 7 to 16 inches, locally lower/higher. Northern NJ and SE NY are expected to end up with 9 to 16 inches of snow, locally higher, with 6 to 12 inches in NYC.


9:20 PM: As of 8 PM, the low pressure is currently located south of eastern Rhode Island and west of about Cape May. After briefly pausing, the intensification trend has resumed, with the minimum pressure down to approximately 982 mb. The low pressure continues to track to the northeast but appears to be slowing down a bit.

As can be expected of most storms, there are parts of the area that are overperforming compared to the forecast, and others that are underperforming. In northwestern New Jersey, not much snow fell so far, while totals have been higher towards NE NJ; totals generally range from 3 to 8 inches so far. New York City is on the low side of totals, with Central Park reporting 2.5 inches as of 7 PM. Meanwhile, portions of Long Island especially further north in Suffolk county into Westchester county are overperforming, with 6 to 12 inches so far. Portions of southern Long Island continue to mix with sleet, and still have lower totals generally between 1 and 5 inches.

Most of the area is still seeing snow, with the exception of parts of southern Long Island still experiencing sleet. Heavy snow rates continue across northern Long Island and parts of Connecticut, with totals over 10 inches reported in some areas. New Jersey has dried up earlier this afternoon, although a narrow yet heavy band of snow remained stalled over extreme NE NJ, in northeastern portions of Bergen county, which did not enter the dry slot at any point. Snow is currently filling in across western New Jersey, with additional moderate to locally heavy snow spreading in and expected to remain in place through the mid overnight hours. Snow rates up to or locally a bit over 1 inch per hour can be expected west of NYC through the mid overnight hours, with at least another 4 to 8 inches of snow expected from NYC and further west.


5:40 PM: As of 5 PM, the low pressure is currently located south of central Long Island and east of extreme southeastern Maryland. The intensification rate has slowed down for now, with the minimum pressure near approximately 985 mb, as it continues to track to the northeast.

Most of the area has changed over to plain snow, with heavy snow rates up to 2-3 inches per hour in parts of Long Island. The heavy snow will continue over Long Island and Connecticut, with the forecast still for totals above 12-18 inches, up to or locally above 24 inches. Further west, the eastern movement of the west end of the precipitation shield has stopped over eastern NJ, with the shield pivoting towards more of a north-south alignment over eastern and NE NJ. As phasing continues to take place, precipitation from central/western New York and Pennsylvania will connect with the precipitation shield over the area, with moderate to locally heavy snow expected from NYC and further north/west through the rest of the evening into the mid overnight hours. In New Jersey, the highest totals are expected in the northeast part of the state with at least 10 to 15 inches of snow; lower totals are expected in NYC with 8 to 14 inches, with western parts of New Jersey expected to end up with at least 7-12 inches, lower in some spots and higher further east.


2:30 PM: As of the latest SPC Mesoanalysis, the low pressure is currently east of the southern tip of the Delmarva Peninsula and south of western Long Island. The low continues to steadily intensify while moving to the northeast, with minimum pressure currently down to 986 millibars.

Over the last 2-3 hours, rain and sleet continued across Long Island, NYC and parts of northern NJ especially south of I-80, although locations south of I-80 including parts of NYC and the northern half of Long Island are either seeing snow or changing to a mix, with heavier precipitation rates expanding north into the area. Precipitation is still struggling to expand into NW NJ, with relatively minor precipitation totals so far.

The low pressure will begin to tilt more to the north over the next few hours, with heavy precipitation moving into Long Island, Connecticut and the immediate NYC area, especially east of NYC, as the rain/snow line continues to shift south. Heavy snow is expected later this afternoon in the aforementioned areas, with snow rates reaching and exceeding 1 inch per hour. Western and central northern New Jersey, however, will remain west of the heavy bands, where lighter snow rates are expected late this afternoon and this evening. Later this evening or early tonight, moderate to heavy snow will spread into the interior western parts of the area as well. Accumulations are expected to end up in the 7-15 inch range in the western half of northern NJ and SE NY, approaching the higher end of this range further east with 10-15 inches in the immediate NYC area, perhaps locally over 15 inches in the snowier case scenario. Long Island and southern Connecticut are still on target to receive heavy snow tonight over 12-18 inches, up to and over 24 inches in some locations in Connecticut.


11:50 AM: The latest radar observations continue to show heavy rain bands over Delaware and southern NJ; despite earlier observations, however, the precipitation shield is now west of the short range HRRR/RAP models which take the heaviest bands noticeably east of NYC, and the latest observations suggest some, but not all, of the models may be a little too far east with the western extent of these bands through the rest of the day. Taking the western extent of the heavier banding over Delaware and drawing a tangent line along the western extent, hypothetically assuming the storm was to continue due NE, the heaviest bands would extend into most of Long Island and central-eastern Connecticut, which are still expected to receive over 12-16 inches with some areas over 20-24 inches. This will likely not be as far west as the bands get, however, as the storm will continue to tilt more towards the north later today, meaning the western extent is likely to end up west of this line through central-western LI and central CT.

Currently, the immediate NYC area (NYC, far southeastern NY, NE NJ) are in the borderline areas regarding the western extent of the banding, where totals are subject to more revisions. Should the heaviest bands stay east of NYC, totals would end up within the previously mentioned range of 7-15 inches west of NYC, leaning towards the higher end of this range (10-15"). Should these bands make the turn earlier, however, higher totals would be expected, potentially within the 12-18 inch range as well. Westernmost parts of the area are currently forecast to receive the 7-15 inch range as well, but are subject to the lower end of the forecast range, 10-12 inches or lower, depending on exactly how far the heaviest bands extend.


10:50 AM: As of this morning, the coastal low pressure continues to intensify; the latest SPC mesoanalysis as of 9 AM shows a 996mb low pressure near the eastern tip of North Carolina. Phasing will take place today as the low pressure continues to intensify and track to the northeast. Precipitation from the coastal low has spread into the area this morning, with the latest radar observations suggesting snow is falling west, southwest and north of NYC including parts of Long Island, with a mix or rain in NYC and further south.

As of last night, the model guidance was still split between an east and west track; the ECM, NAM and SREF were further west, although the NAM was a complete outlier last night with ridiculously high precipitation amounts over all of New Jersey, and has reasonably backed away, a rather large trend considering all of this occurred within 24-36 hours of the storm. The ECM and SREF, however, also corrected slightly further east, which also is supported by the latest observations, which suggest that the heavier precipitation from the coastal low will go into Long Island and southern Connecticut as last night's forecast expected, not in the immediate NYC area as some of the models suggested.

Forecast Update: Last night's discussion mentioned two areas of uncertainty; the western extent of the heavier precipitation from the low pressure, and the duration of mixing with sleet/rain. As of this morning, the southern half of the area is generally mixing with rain and sleet, with the mixing line showing some signs of advancing north. The rain/snow line is not expected to significantly change throughout the day, with the changeover to snow occurring across the area by the late afternoon to evening hours, generally after 5-8 PM when all of the area should change over to snow. The mixing with rain is expected to take up a part of the heavier precipitation of the storm in locations currently seeing mixing.

The second area of uncertainty was regarding how far west the heavy precipitation from the coastal low extends. As previously mentioned, the heavier precipitation will go into southern CT and Long Island, not NYC, but the question remains on how much precipitation does make it to NYC and further north/west, and at least for NYC how much of that falls as snow. Last night's update gave two scenarios; one in which the gradient is further east, with 6-12 inches of snow for NYC and further west with higher totals east of NYC; the second in which the gradient is further west and heavier snow totals spread across the rest of the area. Currently, the former is more of a concern than the second. The latest expectation is for a tight precipitation gradient roughly near NYC; an example of this is with the 12/26/10 blizzard, which also had a tight precipitation gradient over New Jersey, with eastern parts of the state seeing more snow than expected and western parts seeing less than expected.

While higher snow totals are still expected east of NYC, with at least 10 to 20 inches of snow in Long Island and 16 to 24 inches in southern CT, it is possible that totals in NYC, northern NJ and SE NY may end up lower than expected, with additional moderate snow through this evening but without heavy snow rates as the heaviest precipitation stays further south and east, and continued moderate snow overnight across the entire area. The latest forecast is for at least 7 to 15 inches of snow across northern NJ, SE NY and NYC; according to the latest model guidance, totals would mostly stay closer to the upper end of this range, but the lower end cannot be ruled out for parts of the area west of NYC as well, perhaps slightly lower than 7 inches in western areas. Stay tuned for more information on the storm and any changes in the forecast throughout the day.

Reposting the map from last night below - main revisions for the NYC area at this time are to shift the western end of the 12+ inch zone slightly east.



Thursday, February 7, 2013

Feb 7, 2013: Blizzard Expected Tomorrow Night


Forecast Highlights:

After a relatively inactive winter so far, the first blizzard in over 2 years, since January 2011, will affect the area on Friday night, with heavy snowfall and strong winds. While heavy snow will be spread out across the area, the worst of the storm will be focused towards Long Island, Connecticut and close to NYC, where significant snowfall of over 16 inches is expected along with strong winds to result in blizzard conditions.


Afternoon statement


Thursday, 2/7 - 5:35 PM

As mentioned on Twitter earlier today, instead of two separate updates, I am currently working on a single, detailed discussion to be posted soon, later this evening. Another forecast update will be posted on Friday afternoon, followed by live storm updates throughout the evening and parts of the overnight hours tomorrow.

Feb 7, 2013 Morning Update


Urgent Morning Update - Blizzard Increasing In Probability

Last night's update was complicated by the 0z model guidance, which aside from the 0z ECM noticeably shifted southeast with the coastal low; as of last night, there was enough confidence to mention that there was still a possibility that phasing could take earlier with major snowfall extending into NYC, but not enough confidence to fully forecast this scenario. As of this morning, the model guidance continues to correct towards this solution, and at this time there is enough confidence to raise snow accumulations across the area.

As this is a morning update, this will remain brief, with more information to be posted this afternoon. The main factors that could result in lower totals than expected are more mixing with rain/sleet before the changeover to snow, or a slightly further east coastal low which would keep the heaviest snows further east initially. These areas of uncertainty will be addressed in more details later today. Below is the revised forecast for the area, which will be expanded with more information later today:



Light snow is expected to develop across the area on Friday morning, steadily intensifying up to the early afternoon hours. As temperatures aloft and near the surface warm up, a changeover to rain and/or sleet is likely in NYC, Long Island, and possibly NE NJ and coastal Connecticut for the afternoon and evening hours, while interior areas continue to see moderate snow. Accumulations will remain minor through the evening hours, generally up to 3 inches of snow inland and 1-2 inches closer to NYC.

By the evening hours, the coastal low pressure will approach the area, when the most significant impacts from the storm will begin. As temperatures begin to cool down, the rain/snow line will gradually shift southeast through NYC and Long Island in the late evening to early overnight hours, generally after 7-9 PM, with the entire area seeing snow by the early-mid overnight hours. The main question at this time is exactly how far west the deformation band ends up; Long Island and southern CT are likely to be covered by the heavier snow, which combined with strong winds gusting over 40 mph, will result in the potential for blizzard conditions. Thundersnow cannot be ruled out under the heavier snow bands as well. More moderate snow is likely west of NYC, with the snow gradually weakening later in the overnight hours before ending on Saturday morning. For more localized forecasts, please refer to the latest 5-day forecast.

There is still some uncertainty regarding exact accumulations, depending on the focus of the heaviest snow bands and the location of the low pressure, with the latest forecast totals revised to 6-14 inches towards western NJ, 8-18 inches in the immediate NYC area, and 14-24 inches of snow in CT and most of Long Island. These amounts are still subject to change, with more information to be posted later today.

Stay tuned for a more detailed update during the afternoon; tonight's forecast discussion containing a final storm forecast will be posted earlier than usual, in the late afternoon or evening.

Feb 6, 2013: Friday Storm Forecast Update


Forecast Highlights:

Warmer temperatures were observed today, returning closer to average with highs in the upper 30s to low 40s. The main focus at this time is on a storm expected to affect the region on Friday into Friday night; while there remains uncertainty regarding exact impacts in the NYC area, this storm has the capability of producing a significant snowstorm for the Northeast US region, including the NYC area.



Wednesday, February 6, 2013

Feb 6, 2013 Noon Update


Feb 6 Afternoon Update: Major Snowstorm On Track For Friday

Due to the major storm expected to affect the region on Friday, afternoon updates will be posted each day until the storm with any updates and/or changes in the forecast from the last update. The next full discussion will be posted tonight.

Please note that live storm updates for this storm will be slightly delayed and will start on Friday evening, not during the afternoon.



While uncertainty continues with the forecast for the Friday storm, confidence continues to increase that the region as a whole will experience its most significant winter storm in 2 years, since January 26-27, 2011, with potentially historic impacts from this storm in New England, including easternmost parts of the area in eastern Connecticut. By now, most of the models have settled on a major storm affecting the region, except for the NAM which continues to fluctuate with the exact handling of the storm. The question remains the handling of the phasing, with the 0z ECM last night the most bullish with the northern shortwave digging further south and a 500mb low closing off earlier, south of NYC, resulting in a major snowstorm across most of the area with over 20 inches from NYC and further east. Meanwhile, the rest of the models as well as the 12z ECM closed off the 500mb low later, closer to NYC, with the worst of the storm focusing over New England while the area observes rain changing over to moderate snow in the back end of the storm.

Compared to the latest models, the 0z ECM may have taken the trend a little too far and may be exaggerated with the major snow totals near NYC. However, some of the models have been trending towards a stronger low pressure closer to the coast, and confidence increases that the end result may be much more than just a 3-6 inch snow event for most of the area. My preliminary snow forecast will be posted with tonight's discussion, although especially should the coastal low track closer to the coast, which is a potential increasing in probability that needs to be monitored closely, and a scenario I may side closer to for tonight's outlook, more widespread significant to major accumulations are possible across the area, especially over Connecticut and Long Island which may get into the worst conditions of the blizzard; most of the accumulating snow is expected to affect the area starting from the evening. In the axis of the heaviest snow with this storm, currently expected to be over southeastern New England but which could shift closer to the area, widespread totals over 18-24 inches are likely along with blizzard conditions.

Stay tuned for more information with this evening's forecast discussion, which will include a preliminary forecast for the area. A poll has been opened in the right side of the blog regarding snow accumulations in NYC; vote your thoughts in the poll, which will close on Friday morning.

Feb 5, 2013: Significant Storm Possible Friday


Forecast Highlights:

Mainly cloudy skies continued across the area with occasional snow showers, with highs reaching the upper 20s to low 30s across the area. Snow totals fell in the low end of the forecast range, generally under 1/2 inch. Partly sunny skies will return for Wednesday and Thursday with warmer temperatures, ahead of the next storm to affect the region on Friday, which has the makings of a significant storm for parts of the region. After a brief warm up for early next week along with a rain event, a colder pattern is expected to return.


Tuesday, February 5, 2013

Feb 5, 2013 Noon Update


Significant Friday Storm Becoming Likely

Over the last few days, the ECM model has consistently shown a significant coastal storm affecting the region, while the rest of the models showed a significantly weaker system with barely light rain/snow showers. While the ECM has had cases of incorrectly showing a significant storm in the medium range before, in this case it did not back away from the idea, and as of this morning, the majority of the model guidance is starting to trend in this direction.

A more detailed forecast will be posted with tonight's update; based on latest expectations, the set up generally favors New England for a potentially major snowstorm, with at least moderate impacts for the NYC area but with uncertainty regarding the development of the coastal low pressure. At this time, a primary low is expected to hold into New York state with the coastal low developing a little too late for the area to receive a major snowstorm, instead resulting in a moderate rain event with some back end snow, although there is still some room for error with the latest model guidance, with the possibility that this trends towards more snow for the area.

Stay tuned for more information on these changes in the forecast with a detailed evening forecast discussion.

Monday, February 4, 2013

Feb 4, 2013: Snow Again Tonight, Tomorrow


Parts of the forecast have been changed for Friday; an afternoon update will be posted today (2/5/13).

Forecast Highlights:

Cold temperatures continued across the region today, with highs peaking in the upper 20s to low 30s across the area. An active pattern of weak, fast moving light snow events continues with 1/2 to 1 inch of snow possible tonight, followed by another light snow event with up to 1/2 inch on Tuesday night. A warmer pattern will return by the late week into the medium range after a rain/snow storm expected for Friday, although despite the temporarily warmer pattern, winter is not over yet this year.


Feb 3, 2013: More Light Snow This Week


Forecast Highlights:

A minor snow event affected the region last night and today, although snow ended up even more isolated than originally expected with an inverted trough failing to set up over the area with heavier snow as some models indicated; totals ended up generally between 0.5 and 1.5 inch. There's still no big snowstorm in the foreseeable range, although additional minor snow events are expected on Tuesday and Wednesday, followed by a temporary warm up in the pattern by the late week into early next week.


Sunday, February 3, 2013

Feb 3, 2013 Morning Update


10 AM: Storm Mostly Over For Today

Last night, a steady period of light snow affected the area; widespread light accumulations have been reported, with accumulations generally from 1/4 to a little over 1 inch, but since then the snow quickly ended and skies cleared across the area. By this point, it appears that any inverted trough would do little to enhance snow totals except for perhaps areas east and south of NYC, and from this point, little, if any additional snow is expected today for most. Totals will end up close to where they are at this point, if not slightly higher. Should the inverted trough produce additional snow across the area later today, which would focus especially south and east of NYC, additional minor accumulations would take place.

The next update will be posted tonight with more information on the rest of the minor snow events this week.

Saturday, February 2, 2013

Feb 2, 2013: Light Snow Tonight, Tomorrow


Forecast Highlights:

A weak storm is currently affecting the region with widespread light snow showers, with minor accumulations across the area generally under 2 inches through tonight and tomorrow. The cold pattern will continue through most of next week, with another minor snow event expected on Tuesday and Wednesday, followed by a warm up in the pattern by the late week into early next week with some rain and/or snow expected.



Feb 1, 2013: Light Snow Expected Sunday


Forecast Highlights:

Following the strong cold front 2 days ago, another cold day was observed with continued windy conditions behind a weak low pressure that moved off the Mid Atlantic coast earlier today, resulting in localized totals as high as 4-8 inches in southern NJ and Delaware. A few weak storms are expected to affect the region over the next few days with light snow accumulations for the area, while the cold pattern continues through this week.


Friday, February 1, 2013

Feb 1, 2013 Noon Update


4:35 PM: Scattered lake effect snow showers have reached northern NJ earlier this afternoon, with additional scattered snow showers expected to continue this afternoon and evening. Most locations should generally see a dusting of snow, with the potential for totals locally near or above 1/2 inch towards interior areas. This is separate from the system that affected southern New Jersey and Delaware earlier today with as much as 4-8 inches of snow.

The next update will be posted this evening, with more information on the upcoming light snow events.


Jan 31, 2013 Brief Update


Weekend - Next Week: Colder Again, Light Snow Expected

Behind this morning's heavy rain and wind event, temperatures cooled down significantly across the region, with scattered snow showers observed in some areas. A trough is returning to the northeast US throughout the next week, with colder temperatures returning for the weekend through next week peaking in the upper 20s to low 30s for highs, perhaps a bit colder inland and warmer further east.

Along with the cold, several minor snow events are expected. The first will be on Friday, but will remain to the south and east of the area. The next widespread snow event is expected on Sunday, with a weak, moisture-starved low pressure quickly moving through the region; a coastal low pressure is expected to develop, and while it will intensify too late and too far northeast to have significant impacts in the region, there is still some uncertainty with the specifics, and the forecast is subject to minor revisions; at this time, widespread light snow showers are expected with minor accumulations up to potentially 1-2 inches. More information will be posted on this with Friday night's update.

The colder temperatures will continue into next week, with another system affecting the region between Tuesday and Thursday. The model guidance continues to have differences with this one, although the overall expectation is for another weak and relatively dry low pressure, with the potential for additional light snow accumulations across the area. Towards the end of next week and next weekend, the strong cold will retreat back to Canada with an absence of blocking near Greenland to keep the cold trapped further south, with warmer but not very warm temperatures returning into the eastern and central US. The next storm potentials are towards next Friday and early-mid next week; at this time, given the retreating cold and rising 500mb heights in the East, either or both are likely to be on the warmer side with rain or a mix, although the specifics of this time period are still subject to change. More information will be posted on these as details become clearer.