donsutherland1

I had wanted to run the 500 mb composites for NYC's 6" or greater snowstorms during AO-/NAO+ patterns to create clusters. There were 9 such storms. Seven also brought 6" or more to Boston while four also brought 6" or more to Philadelphia (and also Boston). After the 10th, there may be opportunity for a 6"+ snowstorm, but there is no guarantee. New England has a higher probability. The pattern clusters could provide some insight regarding the New York City area. Synoptic details will be crucial, but that information won't become reliable until the closer range when model skill increases. Unfortunately, at present, the site is down.

Yes.

2008-09 reached 10" seasonal snowfall on its 8th day with measurable snowfall. 2006-07 took 12 days to get to 10".

Winds. It also takes time to cool waters that had been abnormally warm coming into the winter.

Today is the 7th day with measurable snowfall. Winter 1937-1938 had 14 days with measurable snowfall with less than 10" of snow. The 15th day reached and exceeded 10".

Maybe at Central Park for a little longer.

Light snow has transitioned to sleet in Larchmont.

For an update on the situation at the NOAA: https://abcnews.go.com/US/doge-now-access-noaas-systems-reviewing-dei-program/story

Colder air has returned to the region just in time for the arrival of another storm. A period of snow, sleet, and freezing rain is likely tonight into tomorrow. New York City and nearby suburbs will likely see 0.5"-1.5" of snow and sleet before a brief transition to freezing rain and then rain. 1"-3" is likely in the distant northern and western suburbs before the precipitation changes over to freezing rain and rain. Northwest New Jersey into adjacent southeast New York could experience an extended period of freezing rain. Another system could bring snow changing to rain on Sunday. No exceptional warmth or cold is likely through at least February 14th. There remains uncertainty about the second half of the month with regard to temperature anomalies. Precipitation will likely be near or somewhat above normal. The AO is now positive and is expected to remain predominantly positive through the first week of February before falling sharply. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. In addition, the NAO is likely to remain at +1.000 or above through the first 10-14 days of February. Since 1950, just 1 of 18 (6%) of storms with an NAO of +0.900 or above saw 6" or more snow in New York City. That storm occurred with an AO of -1.769. As a result, prospects for a 6" or above snowstorm in the New York City area will likely be limited through at least the first 10 days of February. The low probability of a 6" or above snowstorm does not mean that there cannot be snowfall or that there won't be snowfall. Smaller events are possible, as occurred on February 2. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.8°C for the week centered around January 29. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.13°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +24.50 today. The preliminary Arctic Oscillation (AO) was +1.439 today.

There's a lot more than just the models being at risk. NWS forecasting jobs, research, digital content, etc., could all be at risk. There's also the possibility that a lot of what is public could be privatized. Already, the Musk team has made a move in that direction by eliminating the IRS's free e-file platform.

FYI: https://www.theguardian.com/us-news/2025/feb/04/doge-noaa-headquarters

Another brief cold shot is likely tomorrow before temperatures moderate yet again. No exceptional warmth or cold is likely through at least February 10th. A period of snow, sleet, and freezing rain is likely tomorrow night and Thursday. Currently, this appears to be the kind of event that could bring a coating to 1" of snow and sleet to New York City and nearby suburbs and 1"-3" in its distant northern and western suburbs before the precipitation changes over to freezing rain (mainly outside the City) and rain. Northwest New Jersey into adjacent southeast New York could experience an extended period of freezing rain. There remains uncertainty about the second half of the month. Precipitation will likely be near or somewhat above normal. The AO is now positive and is expected to remain predominantly positive through the first week of February before falling sharply. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. In addition, the NAO is likely to remain at +1.000 or above through the first 10-14 days of February. Since 1950, just 1 of 18 (6%) of storms with an NAO of +0.900 or above saw 6" or more snow in New York City. That storm occurred with an AO of -1.769. As a result, prospects for a 6" or above snowstorm in the New York City area will likely be limited through at least the first 10 days of February. The low probability of a 6" or above snowstorm does not mean that there cannot be snowfall or that there won't be snowfall. Smaller events are possible, as occurred on February 2. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.8°C for the week centered around January 29. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.13°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +18.35 today. The preliminary Arctic Oscillation (AO) was +1.701 today.

After the 10th things should be a lot more promising should the AO go negative. An AO-/NAO below +0.8 is viable.

Following last night's light snowfall, the temperature soared well into the 40s across the New York City area. The Philadelphia area saw some lower 50s. Tomorrow will be another mild day, but another brief cold shot is likely Wednesday before temperatures moderate yet again. Some snow, sleet, and freezing rain is also possible later Wednesday into Thursday. There remains some uncertainty about the second half of the month. The ECMWF weeklies are holding with below normal temperatures after having moved to a warmer than normal outlook a few days ago. The AO is now forecast to go strongly negative. These recent developments increase prospects for a colder pattern. Precipitation will likely be near or somewhat above normal. The AO is now positive and is expected to remain predominantly positive through the first week of February before falling sharply. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. In addition, the NAO is likely to remain at +1.000 or above through the first 10-14 days of February. Since 1950, just 1 of 18 (6%) of storms with an NAO of +0.900 or above saw 6" or more snow in New York City. That storm occurred with an AO of -1.769. As a result, prospects for a 6" or above snowstorm in the New York City area will likely be limited through at least the first 10 days of February. The low probability of a 6" or above snowstorm does not mean that there cannot be snowfall or that there won't be snowfall. Smaller events are possible. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.8°C for the week centered around January 29. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.13°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +20.65 today. The preliminary Arctic Oscillation (AO) was +1.329 today.

The final numbers:

Photo from this morning.

Mamaroneck, NY: 0.5"

A photo from a short time ago:

The ground is whitened in Larchmont.

This morning, temperatures were mainly in the teens in and around New York City. Moderation will follow tomorrow, but another brief cold shot is likely around mid-week before temperatures moderate yet again. In addition, a period of light snow or flurries is possible tonight as warmer air moves northward. A coating to an inch is possible, mainly outside New York City. Some of the distant suburbs could pick up 1"-3" of snow. There remains uncertainty about the second half of the month. The ECMWF weeklies have now shifted to below normal temperatures after moving to a warmer than normal outlook. The AO is now forecast to go strongly negative. These recent developments increase prospects for a colder pattern. Precipitation will likely be near or somewhat above normal. The AO is now positive and is expected to remain predominantly positive through the first week of February before falling sharply. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. In addition, the NAO is likely to remain at +1.000 or above through the first 10-14 days of February. Since 1950, just 1 of 18 (6%) of storms with an NAO of +0.900 or above saw 6" or more snow in New York City. That storm occurred with an AO of -1.769. As a result, prospects for a 6" or above snowstorm in the New York City area will likely be limited through at least the first 10 days of February. The low probability of a 6" or above snowstorm does not mean that there cannot be snowfall or there won't be snowfall. Smaller events are possible. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +20.51 today. The preliminary Arctic Oscillation (AO) was +0.913 today.

Nice shift to colder on the ECMWF weeklies.

If the WxBell (and also WxModels) GEFS idea is to verify, it would have to exceed the largest 14-day error over the last three months by easily the largest margin. I am increasingly beginning to question whether it makes sense to continue to subscribe to paid plans with what appears to be a growing amount of questionable or incorrect data. I suspect the same programming flaw that produces the GEFS maps is also responsible for the low NAO values on the EPS and ECMWF. A negative NAO is plausible by mid-month (not assured), but a -2.000 or below value seems very unlikely.

I only have vendor information. The ECMWF does not post teleconnection charts, so I can't verify whether a similar issue exists. The AI number is all but certain to be wrong. The record low value for the NAO is -3.254.

The NAO chart is suspect. Here's the GEFS forecast from NCEP: On the official site, not a single member of the GEFS forecasts an NAO value near -2.000 by February 15. Also, for February 2010, the NAO was at or below -1.000 on 14/28 (50%) days and < 0 on all 28 days. That is not going to be the case this February. The NAO's preliminary values for February 1 and 2 are +1.269 and +1.535. A February 2010 NAO scenario is not on the table.