donsutherland1

Morning thoughts... Light to moderate snow was still falling over parts of central and southern New Jersey and into southeastern Pennsylvania this morning. Philadelphia had picked up 3.1” snow. In Nassau County, Elmont (1 WNW) had received 4.2”. There will likely be some breaks in the clouds and sunshine for a time, especially from New York City northward. Temperatures will likely top out in the lower and middle 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 35° Newark: 34° Philadelphia: 35° Tomorrow will be partly cloudy. Another system could bring some light snow to parts of the region on Sunday.

A light snowfall is possible late tonight into tomorrow. Accumulations should generally reach 1" or less in New York City's nearby northern and western suburbs, 1"-3" in New York City, and 2"-4" across parts of central New Jersey and southeastern Pennsylvania, including Philadelphia. A blend of the guidance suggests the following snowfall amounts: New York City: 1.8"; Newark: 2.1"; and, Philadelphia: 3.4" As a result, New York City's Central Park will record its first month with 20" or more snow since 27.9" fell in January 2016 and its first February with 20" or more snow since 2014 when 29.0" was measured. Philadelphia will likely see its first month with 10" or more snow since March 2018 when 15.2" was recorded and its first February with 10" or more snow since 2014 when 22.4" fell. Another weak system will pass even farther south on Friday. Today saw more near record and record cold in parts of western Canada and also Montana. Select low temperatures: Cut Bank, MT: -38° (old record: -33°, 1939) ***Coldest day since February 8, 1994*** Dease Lake, BC: -40° (old record: -35°, 2017) Havre, MT: -33° Medicine Hat, AB: -27° (-17°, 2014) Prince George, BC: -35° (old record: -32°, 1948) Thompson, MB: -44° That frigid air mass will slowly advance eastward and possibly reach the Middle Atlantic and southern New England regions around mid-month. There is some uncertainty as to whether this air mass will move directly into the region sending temperatures into the single digits even in New York City or merely pass nearby delivering a glancing blow with single-digit cold avoiding New York City but affecting areas outside of New York City and Newark. The probability of the latter outcome has continued to increase. It is more likely than not that the latter scenario will play out. The Arctic Oscillation (AO) is now severely negative and at its lowest levels in nearly eight years. It is forecast to rise sharply toward mid-month. A dramatic increase in the AO has sometimes coincided with storminess. Therefore, the February 14-24 period might offer a window of opportunity for a meaningful storm. Details about possible storm tracks or precipitation types are premature at this point. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +20.03 today. Today, the preliminary Arctic Oscillation (AO) figure was -5.152 today. That is the lowest AO figure since the AO was -5.240 on March 22, 2013. The last time the AO was at -5.000 or below in February was February 14, 2010 when the AO was -5.132. On February 9 the MJO was in Phase 7 at an amplitude of 2.246 (RMM). The February 8-adjusted amplitude was 2.143. Based on the latest guidance, no significant stratospheric warming event is likely through the middle of the third week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 22.0" snow. Based on sensitivity analysis applied to the latest guidance, there is an implied 82% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.3° (3.0° below normal).

There was no LGA or JFK at that time. However, Flushing reported a low of -14 degrees.

Probably 2” or maybe 3”.

The HREF bumped up. 1”-2” amounts are possible in NYC with the higher figure more likely in parts of Queens, Brooklyn and Staten Island than Central Park.

Morning thoughts... Today will be partly to mostly cloudy and somewhat colder than normal. Temperatures will likely top out in the lower and middle 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 32° Newark: 34° Philadelphia: 35° A weak system will pass eastward across the Middle Atlantic region. It could bring a small accumulation of snow to New York City and its nearby northern suburbs. The northward extent of 1”-3” snows will likely be across central New Jersey.

A weak system tracked somewhat farther to the north than had been modeled. As a result, accumulating snow was confined to the north and west of New York City and its nearby suburbs. The 0z HREF did well to catch the shift in snowfall. Following the departure of this weak system, tomorrow should be partly sunny. Temperatures will run several degrees below normal. Afterward, another light snowfall is possible on Thursday and/or Friday particularly from central Pennsylvania to central New Jersey and southward. Meanwhile, parts of western Canada experienced near record cold and record cold temperatures. Minimum temperatures included: Burwash Landing, YT: -49°;Carmacks, YT: -56° (old record: -54°, 2008); Dease Lake, BC: -43° (old record: -28°, 2017); Faro, YT: -50° (old record: -48°, 1979); Norman Wells, NT: -48° Whitehorse, YT: -44° That frigid air mass will slowly advance eastward and possibly reach the Middle Atlantic and southern New England regions around mid-month. There is some uncertainty as to whether this air mass will move directly into the region sending temperatures into the single digits even in New York City or merely pass nearby delivering a glancing blow with single-digit cold avoiding New York City but affecting areas outside of New York City and Newark. The probability of the latter outcome has increased in recent days. The Arctic Oscillation (AO) is now severely negative and at its lowest levels in more than five years. It is forecast to rise sharply toward mid-month. A dramatic increase in the AO has sometimes coincided with storminess. Therefore, the February 14-24 period might offer a window of opportunity for a meaningful storm. Details about possible storm tracks or precipitation types are premature at this point. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +30.93 today. Today, the preliminary Arctic Oscillation (AO) figure was -4.618 today. That is the lowest AO figure since the AO was -4.898 on January 16, 2016. On February 8 the MJO was in Phase 7 at an amplitude of 2.142 (RMM). The February 7-adjusted amplitude was 2.121. Based on the latest guidance, no significant stratospheric warming event is likely through the middle of the third week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 22.0" snow. Based on sensitivity analysis applied to the latest guidance, there is an implied 84% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.3°.

30” is still the on the table. A lot will depend on the second half of the month.

Some drizzle in Larchmont with occasional pellets of sleet. The temperature is just above freezing.

A few flurries fell in Larchmont where schools were closed. It was snowing lightly in Armonk at 8 am with 1” on the ground.

Morning thoughts... At 6:55 am, light snow was falling north and west of New York City. The areas of light snow were somewhat north of where they had been modeled. The light snow will continue to fall in parts of the region,mainly north of New York City little or no snow accumulation (0.5” or less). There will be 1"-3" snow approximately 25-50 miles north and west of New York City. Some embedded pockets of 4" or greater amounts are possible in that area. Temperatures will likely top out in the middle and upper 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 35° Newark: 36° Philadelphia: 40° Tomorrow will be a dry day.

Through today, February 2021 has seen 19.9" snow in New York City. February has accounted for 16 of the 35 (46%) of monthly cases with 20.0" or more snow. Four of those cases have occurred since 2000. The most recent February with 20.0" or more snow occurred in 2014 when 29.0" was recorded. The last month in which 20.0" or more snow fell was January 2016 when monthly snowfall came to 27.9". February 2021 will very likely reach and then exceed 20.0" monthly snowfall this week. There is some possibility that February's total snowfall could reach 30.0", especially if ongoing blocking persists. Since recordkeeping began in 1869, there are only three cases where monthly snowfall reached 30.0" or more in New York City and two of those cases have occurred since 2000. A light snow event could affect parts of the region tomorrow. New York City will likely see 1"-2" snow. There will be 2"-4" snow approximately 25-50 miles north and west of New York City. Some embedded pockets of 6" amounts are possible in that area. Some of the areas that largely missed out on Sunday's snowfall should be the beneficiaries of these heavier amounts this time around. Wednesday should be dry. Afterward, another light snowfall is possible on Thursday and/or Friday. A frigid air mass will slowly advance eastward and possibly reach the Middle Atlantic and southern New England regions around mid-month. There is some uncertainty as to whether this air mass will move directly into the region sending temperatures into the single digits even in New York City or merely pass nearby delivering a glancing blow with single-digit cold avoiding New York City but affecting areas outside of New York City and Newark. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +28.44 today. Today, the preliminary Arctic Oscillation (AO) figure was -4.290 today. That is the lowest AO figure since the AO was -4.426 on March 2, 2018. On February 7 the MJO was in Phase 7 at an amplitude of 2.121 (RMM). The February 6-adjusted amplitude was 2.145. Based on the latest guidance, no significant stratospheric warming event is likely through the second week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 22.0" snow. Based on sensitivity analysis applied to the latest guidance, there is an implied 79% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.5°.

There’s a lot more variability now. It’s a different climate regime than it was even 30 years ago.

32.5” for winter 2020-21.

Morning thoughts... Today will be partly sunny and unseasonably cold. Temperatures will likely top out in the upper 20s and lower 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 29° Newark: 30° Philadelphia: 32° A system will likely bring a swath of 1”-3” snow to parts of the region with local amounts of up to 4”, especially north and west of Newark and New York City. Central Park could even pick up an inch or two of snow, but there is uncertainty about the southern extent of the snow.

Final at JFK: 6.9”. It was a nice storm.

Today's storm brought a large swath of 4"-8" snows with some locally higher amounts to the New York City region. Even heavier amounts were reported in parts of New England. Select accumulations included: Bridgeport: 7.4" East Killingly, CT: 9.6" Islip: 5.1" New York City: 4.5" Newark: 5.6" Norfolk, MA: 12.0" Sharon, MA: 12.0" Syosset (1 N), NY: 8.4" Westwood (1 NNE), NJ: 9.1" Another light snow event could affect parts of the region on Tuesday. Up in Canada's Nunavut Province, temperatures will reach record high levels tomorrow through at least Monday. That push of exceptional warmth will dislodge a frigid Arctic air mass currently located over northwestern Canada. That cold air mass will likely enter the Northern Plains States early next week. Afterward, it could slowly advance eastward and possibly reach the Middle Atlantic and southern New England regions just before mid-month. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.7°C for the week centered around January 27. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.71°C and the ENSO Region 3.4 anomaly has averaged -1.03°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +13.26 today. Today, the preliminary Arctic Oscillation (AO) figure was -3.730 today. On February 6 the MJO was in Phase 7 at an amplitude of 2.145 (RMM). The February 5-adjusted amplitude was 2.115. Based on the latest guidance, no significant stratospheric warming event is likely through the second week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 22.0" snow. Based on sensitivity analysis applied to the latest guidance, there is an implied 80% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.5°.

Five photos from today’s snowstorm:

Around 8” in Rye. Light snow continues to fall.

A quick video clip:

4” in Mamaroneck, NY.

Snow has just moved into Larchmont, NY in southern Westchester County. After a short period of flurries, it is now snowing moderately.

Morning thoughts... On this date in 1967, a major snowstorm was burying the region. This time around, a fast-moving system will provide parts of the region with a period of heavy snow, but smaller accumulations are likely. New York City, Newark, and Philadelphia will likely pick up 3”-6” snow while Islip sees 4”-8”. Locations such as Newburgh and Poughkeepsie should pick up 2”-4” snow. The HREF ensemble system shows a large area of 4”-6” snows with 6”-8” (and even an area of 8”-10” on eastern Long Island) across northeast New Jersey and eastward. This data provides some confidence that total snowfall will likely exceed the lowest amounts shown on some of the global models. At 8:40 am, the first snow was falling in parts of New York City, including Brooklyn and flurries extended into southern Westchester County. Snow will fall moderately to occasionally heavily at times, especially from late morning into the afternoon. Where banding develops, snow could fall at a rate of 1” per hour. Temperatures will likely top out in the lower and middle 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 35° Newark: 35° Philadelphia: 36° Tomorrow will be fair and cold, but another system could bring a period of light snow on Tuesday. Areas to the north and west of Newark and New York City have the best chance of seeing accumulating snow from that system.

A developing fast-moving storm will bring a swath of snow across parts of the region tomorrow with the highest amounts occurring along the coastline from central New Jersey to southern New England, including Long Island. There is some uncertainty as to how far north the heaviest bands will make it. The 12z HREF and 18z NAM and HRRR favor their being located farther north consistent with the modeled lift. At present, on account of some of the major global guidance and the 3 km NAM favoring a further south positioning of the bands, a compromise idea is adopted. Snowfall estimates for select cities: Boston: 4"-8" Bridgeport: 3"-6" Islip: 4"-8" New York City: 3"-6" Newark: 3"-6" Philadelphia: 3"-6" Poughkeepsie: 2"-4" Providence: 4"-8" Another light snow event could affect parts of the region on Tuesday. Up in Canada's Nunavut Province, temperatures will reach record high levels tomorrow through at least Monday. That push of exceptional warmth will dislodge a frigid Arctic air mass currently located over northwestern Canada. That cold air mass will likely enter the Northern Plains States early next week. Afterward, it could slowly advance eastward and possibly reach the Middle Atlantic and southern New England regions just before mid-month. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.7°C for the week centered around January 27. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.71°C and the ENSO Region 3.4 anomaly has averaged -1.03°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +0.62 today. Today, the preliminary Arctic Oscillation (AO) figure was -3.224 today. On February 5 the MJO was in Phase 7 at an amplitude of 2.111 (RMM). The February 4-adjusted amplitude was 2.001. Based on the latest guidance, no significant stratospheric warming event is likely through the second week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 17.5" snow.

From the discussion, details about the dynamics the NWS was relying on more than just the modeled QPF: THE GFS SHOWS EXCELLENT LIFT IN THE DENDRITIC GROWTH ZONE (-12C TO -18C) EVEN AS FAR NORTH AS THE LOWER HUDSON VALLEY WHERE CURRENT FORECAST LIQUID AMOUNTS ARE LOWER. FRONTOGENESIS ON THE NW SIDE OR COLDER SIDE OF THE MIDDLE LEVEL LOW IS IMPRESSIVE FOR ABOUT A 3-6 HOUR PERIOD FROM LATE MORNING INTO THE AFTERNOON ACROSS MUCH OF THE REGION.