bluewave

Just updating for the newer data on 12-17 vs 12-10. The EPS is around a 0 to +1 the rest of the month. So that would yield a 7 station average of around -3 to -4 from the current -7.7. Long Island is running a little warmer and is only -5.5 at ISP through the 16th.

This is going to be one of the strongest -WPO blocks that we have seen for the month of December. But it’s a different configuration of other factors that we have previously seen with December -WPOs in the past. This one has a much more amplified Pacific Jet into the PACNW and BC than we have seen before with the historic flooding in those areas. Plus we have an out of phase +EPO and very strong ridge onto the Western US. Unique December 2025 500 mb and Pacific Jet stream pattern compared to previous very strong -WPO patterns

All we can say is that the first 16 days of December have been one of our coldest 16 day periods relative to the means of the 2020s so far. The clipper was a nice contribution to this period feeling very wintry around the area. This was actually the coldest first half of December in 20 years. The new Newark records for December now go back to 1850. So this was ranked 26th coldest which is very respectable in our warmer 2020s climate. The current 7 station departure across the area is -7.7. With the moderation coming up next few weeks, the final number this month may finish in the -3 to -4 range. Models have been fluctuating from run to so we won’t know the exact number for a weeks. EWR…..-8.1 NYC……-8.7 LGA……-8.7 JFK…….-7.8 HPN……-7.6 BDR…...-7.9 ISP……..-5.4 AVG…….-7.7 Time Series Summary for NEWARK LIBERTY INTL AP, NJ Coldest 12-01 to 12-16 periods Click column heading to sort ascending, click again to sort descending. 1 1867-12-16 24.1 5 2 1904-12-16 24.6 0 3 1910-12-16 25.5 0 4 1917-12-16 25.7 4 5 1876-12-16 27.0 5 6 1868-12-16 27.3 3 7 1958-12-16 27.9 0 - 1871-12-16 27.9 1 8 1902-12-16 28.6 0 9 1989-12-16 28.8 0 - 1869-12-16 28.8 4 10 1860-12-16 28.9 2 11 1880-12-16 29.0 3 12 1895-12-16 29.1 2 13 1859-12-16 29.4 4 14 1886-12-16 29.5 4 15 1882-12-16 29.7 2 16 1915-12-16 29.8 1 17 1903-12-16 30.0 0 - 1872-12-16 30.0 2 18 2005-12-16 30.4 0 19 1976-12-16 30.6 0 20 1854-12-16 30.8 3 21 1898-12-16 31.0 0 22 1937-12-16 31.1 0 23 1942-12-16 31.2 0 24 1875-12-16 31.4 0 25 1851-12-16 31.7 4 26 2025-12-16 31.8 0 - 1945-12-16 31.8 0

Interesting new study confirming other recent studies that the cold pool in the North Atlantic is more a sign of the atmospheric patterns rather than an AMOC decline. Anthony Masiello ‪@antmasiello.bsky.social‬ Follow Natural variability, in low frequency states of atmospheric circulation, is becoming increasingly likely as the main explanation for the North Atlantic warming hole. ‪Sang-Ki Lee‬ ‪@sklee621.bsky.social‬ · 1mo The Atlantic's warming hole is not a sign of the AMOC weakening, a new study suggests ocean2climate.org/2025/11/12/t... The Atlantic’s ‘Warming Hole’ Isn’t What You Think: 5 Surprising Truths From New Climate Research This blog post and the “Deep Drive” podcast on a new paper “Atmosphere-driven processes in shaping long-term climate variability in Greenland and the broader subpolar North Atlant… ocean2climate.org 11:10 AM · Nov 12,

You have a great eye for photography and video like Don. I used to be much more active in photography years ago. Enjoyed walking around and taking photos in Manhattan. I would shoot rolls of Kodachrome 64 color snd Tri-x 400 black film. There was an old place that rented darkrooms by the hour at 20W 20th street to develop the black and white. It’s much more convent these days with mobile photography and software.

Most of us on here describe lows which track to our west as a cutter. Sometimes they ride north of the Great Lakes traveling from west to east. Other times they start out near the Gulf or Southeastern States and lift up through the Eastern Lakes anywhere from Cleveland to Eastern PA into Canada. Either way parts of the region at least make into at least the 50s with mostly rain that can be heavy with a SE to SW flow. The strongest cutter that I experienced since the 1990s was 11-11-95. A deep low rode north near the APPS into Canada and a secondary developed just to our west. This delivered 70-75 mph gusts in Long Beach which the western half of town losing power for nearly 24hrs. The worst flood cutter I remember here was later in January 1996 with a deep snowpack. All the roads were like rivers in Long Beach as the giant snow piles on the side of the road blocked the storm drains. The most recent damaging flood cutter upstate was 12-25-20. The 40” +record snow pack rapidly melted and lead to serious flash flooding with 1.50” of rain and landslides damaging the ski resorts.

Still looks like the classic cutter track. I shoveled out around my storm drains yesterday. These rain events which follow snow within a few days tend to at least cause street flooding if the storm drains still have snow over them.

It was just nice to finally see a widespread 4-8” clipper which used to be very common in the old days. I wonder if we can find a way to sneak in a KU that rapidly deepens near the benchmark with some portion of the area going 12” before the end of the season? My guess is that we will probably need at least one of these events for most spots from Newark out across Long Island to make it to closer to the long term average in the mid 20s for snowfall. It would be nice to finally see a bounce back year after the repeated lower totals last 7 years and lack of KU events. I have been looking at the La Niña December snowfall in more detail last few days to try to find where a cutoff may be for average to above average snowfall. Previously used a 4” snowfall total for a rough approximation of a cutoff. Correcting for the Central Park under measurement they should be right at 4” and Newark is 4.2”. But all of the average to above snowfall seasons had 7.7”+in December like 2020, 2017, 2010, 2008, 2005, 2000, and 1995. The one exception was 2016. So it’s possible that the actual cutoff could be in the 4-7”range. It will be interesting to see how things work out the rest of the season. I am posting the Newark data below instead of NYC since they have a paid contract observer there. Even adding a bit to the NYC totals getting them closer to Newark shows the same relationship. 15 most recent La Niña Decembers using RONI and Total Seasonal Snowfall at Newark 24-25….3.5”…..13.6” 22-23….0.1”……2.7” 21-22….0.1”……17.9” 20-21…..11.9”…45.7” 17-18…….7.7”….39.4” 16-17……3.4”….30.0”…..The one year the relationship didn’t work out 11-12……0.0…..8.8” 10-11…..24.5”…68.2” 08-09….8.3”….27.1” 07-08….3.9”….14.6” 05-06….11.0”….37.9” 00-01….14.9”….39.3” 99-00……T…….18.4” 98-99….1.2”…..12.8” 95-96….12.8”….78.4”

It was just nice to finally see a widespread 4-8” clipper which used to be very common in the old days. I wonder if we can find a way to sneak in a KU that rapidly deepens near the benchmark with some portion of the area going 12” before the end of the season? My guess is that we will probably need at least one of these events for most spots from Newark out across Long Island to make it to closer to the long term average in the mid 20s for snowfall. It would be nice to finally see a bounce back year after the repeated lower totals last 7 years and lack of KU events. I have been looking at the La Niña December snowfall in more detail last few days to try to find where a cutoff may be for average to above average snowfall. Previously used a 4” snowfall total for a rough approximation of a cutoff. Correcting for the Central Park under measurement they should be right at 4” and Newark is 4.2”. But all of the average to above snowfall seasons had 7.7”+in December like 2020, 2017, 2010, 2008, 2005, 2000, and 1995. The one exception was 2016. So it’s possible that the actual cutoff could be in the 4-7”range. It will be interesting to see how things work out the rest of the season. I am posting the Newark data below instead of NYC since they have a paid contract observer there. Even adding a bit to the NYC totals getting them closer to Newark shows the same relationship. 15 most recent La Niña Decembers using RONI and Total Seasonal Snowfall at Newark 24-25….3.5”…..13.6” 22-23….0.1”……2.7” 21-22….0.1”……17.9” 20-21…..11.9”…45.7” 17-18…….7.7”….39.4” 16-17……3.4”….30.0”…..The one year the relationship didn’t work out 11-12……0.0…..8.8” 10-11…..24.5”…68.2” 08-09….8.3”….27.1” 07-08….3.9”….14.6” 05-06….11.0”….37.9” 00-01….14.9”….39.3” 99-00……T…….18.4” 98-99….1.2”…..12.8” 95-96….12.8”….78.4”

Mid-December has been prime time for snow across the region since 2011. Time Series Summary for NEWARK LIBERTY INTL AP, NJ 12-01 to 12-10 snowfall Click column heading to sort ascending, click again to sort descending. 2025-12-10 0.1 0 2024-12-10 T 0 2023-12-10 T 0 2022-12-10 T 0 2021-12-10 T 0 2020-12-10 0.5 0 2019-12-10 2.5 0 2018-12-10 T 0 2017-12-10 4.3 0 2016-12-10 T 0 2015-12-10 0.0 0 2014-12-10 0.1 0 2013-12-10 3.1 0 2012-12-10 0.0 0 2011-12-10 0.0 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY 12-01 to 12-10 snowfall Click column heading to sort ascending, click again to sort descending. 2025-12-10 T 0 2024-12-10 T 0 2023-12-10 T 0 2022-12-10 0.0 0 2021-12-10 T 0 2020-12-10 T 0 2019-12-10 1.9 0 2018-12-10 T 0 2017-12-10 1.3 0 2016-12-10 0.0 0 2015-12-10 0.0 0 2014-12-10 0.1 0 2013-12-10 1.6 0 2012-12-10 0.0 0 2011-12-10 T 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ 12-11 to 12-20 snowfall Click column heading to sort ascending, click again to sort descending. 2025-12-20 4.1 6 2024-12-20 0.3 0 2023-12-20 0.0 0 2022-12-20 0.1 0 2021-12-20 0.0 0 2020-12-20 11.4 0 2019-12-20 1.7 0 2018-12-20 T 0 2017-12-20 2.8 0 2016-12-20 3.4 0 2015-12-20 0.0 0 2014-12-20 0.2 0 2013-12-20 6.3 0 2012-12-20 0.0 0 2011-12-20 0.0 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY 12-11 to 12-20 snowfall Click column heading to sort ascending, click again to sort descending. 2025-12-20 5.8 6 2024-12-20 T 0 2023-12-20 0.0 0 2022-12-20 0.4 0 2021-12-20 0.0 0 2020-12-20 7.5 0 2019-12-20 2.3 0 2018-12-20 T 0 2017-12-20 3.4 0 2016-12-20 3.2 0 2015-12-20 0.0 0 2014-12-20 0.3 0 2013-12-20 4.8 0 2012-12-20 0.0 0 2011-12-20 0.0 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ 12-21 to 12-31 snowfall Click column heading to sort ascending, click again to sort descending. 2024-12-31 3.2 0 2023-12-31 0.0 0 2022-12-31 T 0 2021-12-31 0.1 0 2020-12-31 0.0 0 2019-12-31 0.0 0 2018-12-31 T 0 2017-12-31 0.6 0 2016-12-31 T 0 2015-12-31 0.3 0 2014-12-31 T 0 2013-12-31 T 0 2012-12-31 1.9 0 2011-12-31 0.0 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY 12-21 to 12-31 snowfall Click column heading to sort ascending, click again to sort descending. 2024-12-31 2.1 0 2023-12-31 0.0 0 2022-12-31 0.0 0 2021-12-31 0.3 0 2020-12-31 0.0 0 2019-12-31 0.0 0 2018-12-31 T 0 2017-12-31 1.3 0 2016-12-31 0.0 0 2015-12-31 T 0 2014-12-31 0.0 0 2013-12-31 1.7 0 2012-12-31 0.6 0 2011-12-31 0.0 0

It wouldn’t be the first low snowfall measurement there. I have pointed this out in the past with multiple other posters here. The actual measurement was probably closer to the 4.0” at Newark. Thanks for posting the video. It may have been Sam Champion last year showing closer to 1” too low in one of the events where he used his own measurement.

Maybe an XMACIS glitch since it’s now back down to 2.9”. Very similar to LGA. Climatological Data for NY CITY CENTRAL PARK, NY - December 2025 Click column heading to sort ascending, click again to sort descending. Sum 552 379 - - 442 0 1.41 2.9 2025-12-01 43 34 38.5 -4.7 26 0 0.00 0.0 0 2025-12-02 40 34 37.0 -5.9 28 0 0.78 0.0 0 2025-12-03 41 31 36.0 -6.6 29 0 0.00 0.0 0 2025-12-04 41 24 32.5 -9.8 32 0 0.00 0.0 0 2025-12-05 32 20 26.0 -16.0 39 0 0.00 0.0 0 2025-12-06 42 30 36.0 -5.7 29 0 0.02 T 0 2025-12-07 43 34 38.5 -2.9 26 0 0.00 0.0 0 2025-12-08 38 22 30.0 -11.1 35 0 0.00 0.0 0 2025-12-09 35 19 27.0 -13.9 38 0 0.00 0.0 0 2025-12-10 47 32 39.5 -1.1 25 0 0.07 0.0 0 2025-12-11 41 28 34.5 -5.8 30 0 0.00 0.0 0 2025-12-12 35 25 30.0 -10.0 35 0 0.00 0.0 0 2025-12-13 41 27 34.0 -5.7 31 0 0.03 T 0 2025-12-14 33 19 26.0 -13.5 39 0 0.51 2.9 1 2025-12-15 M M M M M M M M M 2025-12-16 M M M M M M M M M 2025-12-17 M M M M M M M M M 2025-12-18 M M M M M M M M M 2025-12-19 M M M M M M M M M 2025-12-20 M M M M M M M M M 2025-12-21 M M M M M M M M M 2025-12-22 M M M M M M M M M 2025-12-23 M M M M M M M M M 2025-12-24 M M M M M M M M M 2025-12-25 M M M M M M M M M 2025-12-26 M M M M M M M M M 2025-12-27 M M M M M M M M M 2025-12-28 M M M M M M M M M 2025-12-29 M M M M M M M M M 2025-12-30 M M M M M M M M M 2025-12-31 M M M M M M M M M Climatological Data for LAGUARDIA AIRPORT, NY - December 2025 Click column heading to sort ascending, click again to sort descending. Sum 562 395 - - 428 0 1.49 2.6 - Average 40.1 28.2 34.2 -8.1 - - - - 2025-12-01 43 35 39.0 -5.2 26 0 0.00 0.0 0 2025-12-02 42 34 38.0 -5.9 27 0 0.82 0.0 0 2025-12-03 42 33 37.5 -6.1 27 0 0.00 0.0 0 2025-12-04 43 25 34.0 -9.3 31 0 0.00 0.0 0 2025-12-05 32 20 26.0 -17.0 39 0 0.00 0.0 0 2025-12-06 43 32 37.5 -5.2 27 0 0.02 T T 2025-12-07 43 36 39.5 -2.9 25 0 0.00 0.0 0 2025-12-08 40 23 31.5 -10.7 33 0 0.00 0.0 0 2025-12-09 35 20 27.5 -14.4 37 0 0.00 0.0 0 2025-12-10 47 33 40.0 -1.6 25 0 0.09 0.0 0 2025-12-11 41 29 35.0 -6.3 30 0 0.00 0.0 0 2025-12-12 36 26 31.0 -10.0 34 0 0.00 0.0 0 2025-12-13 41 28 34.5 -6.3 30 0 0.03 T 0 2025-12-14 34 21 27.5 -13.0 37 0 0.53 2.6 2 2025-12-15 M M M M M M M M M 2025-12-16 M M M M M M M M M 2025-12-17 M M M M M M M M M 2025-12-18 M M M M M M M M M 2025-12-19 M M M M M M M M M 2025-12-20 M M M M M M M M M 2025-12-21 M M M M M M M M M 2025-12-22 M M M M M M M M M 2025-12-23 M M M M M M M M M 2025-12-24 M M M M M M M M M 2025-12-25 M M M M M M M M M 2025-12-26 M M M M M M M M M 2025-12-27 M M M M M M M M M 2025-12-28 M M M M M M M M M 2025-12-29 M M M M M M M M M 2025-12-30 M M M M M M M M M 2025-12-31 M M M M M M M M M

Walt, you always do a fantastic job. You are a living legend in this business and I hope you enjoy taking more time for home and family. Anything you can find time to post on here will be much appreciated. But I can understand you needing to focus on other things in life. I got my first internet connection and computer in January 1997. I quickly found that your AFDs were the best weather discussions going at the time. I didn’t know much about teleconnections or weather patterns in general. But I slowly learned by reading you rich and in depth discussions. When you first joined this forum, I almost couldn’t believe it. Just very grateful for you to have chosen our forum to share all your valuable knowledge. So wish you all the best of luck in your future endeavors.

Anyone know why two different snowfall amounts are showing up for NYC? CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 159 AM EST MON DEC 15 2025 ................................... ...THE CENTRAL PARK NY CLIMATE SUMMARY FOR DECEMBER 14 2025... CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1869 TO 2025 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) YESTERDAY MAXIMUM 33 630 AM 67 1881 45 -12 34 2015 MINIMUM 19 1159 PM 12 1976 34 -15 26 AVERAGE 26 40 -14 30 PRECIPITATION (IN) YESTERDAY 0.51 2.22 1897 0.15 0.36 0.00 MONTH TO DATE 1.41 2.07 -0.66 1.39 SINCE DEC 1 1.41 2.07 -0.66 1.39 SINCE JAN 1 37.60 47.21 -9.61 43.23 SNOWFALL (IN) YESTERDAY 2.9 5.8 2003 0.2 2.7 0.0 MONTH TO DATE 2.9 1.7 1.2 T SINCE DEC 1 2.9 1.7 1.2 T SINCE JUL 1 2.9 2.3 0.6 T SNOW DEPTH 1 Climatological Data for NY CITY CENTRAL PARK, NY - December 2025 Click column heading to sort ascending, click again to sort descending. Sum 552 379 - - 442 0 1.41 4.4 2025-12-01 43 34 38.5 -4.7 26 0 0.00 0.0 0 2025-12-02 40 34 37.0 -5.9 28 0 0.78 0.0 0 2025-12-03 41 31 36.0 -6.6 29 0 0.00 0.0 0 2025-12-04 41 24 32.5 -9.8 32 0 0.00 0.0 0 2025-12-05 32 20 26.0 -16.0 39 0 0.00 0.0 0 2025-12-06 42 30 36.0 -5.7 29 0 0.02 T 0 2025-12-07 43 34 38.5 -2.9 26 0 0.00 0.0 0 2025-12-08 38 22 30.0 -11.1 35 0 0.00 0.0 0 2025-12-09 35 19 27.0 -13.9 38 0 0.00 0.0 0 2025-12-10 47 32 39.5 -1.1 25 0 0.07 0.0 0 2025-12-11 41 28 34.5 -5.8 30 0 0.00 0.0 0 2025-12-12 35 25 30.0 -10.0 35 0 0.00 0.0 0 2025-12-13 41 27 34.0 -5.7 31 0 0.03 T 0 2025-12-14 33 19 26.0 -13.5 39 0 0.51 4.4 3 2025-12-15 M M M M M M M M M 2025-12-16 M M M M M M M M M 2025-12-17 M M M M M M M M M 2025-12-18 M M M M M M M M M 2025-12-19 M M M M M M M M M 2025-12-20 M M M M M M M M M 2025-12-21 M M M M M M M M M 2025-12-22 M M M M M M M M M 2025-12-23 M M M M M M M M M 2025-12-24 M M M M M M M M M 2025-12-25 M M M M M M M M M 2025-12-26 M M M M M M M M M 2025-12-27 M M M M M M M M M 2025-12-28 M M M M M M M M M 2025-12-29 M M M M M M M M M 2025-12-30 M M M M M M M M M 2025-12-31 M M M M M M M M M

1.7” so far at LGA.

Yeah, this system has been getting stronger on the recent model runs. New run Old run

It’s nice to see North America doing better than Eurasia on snow extent for a change. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_monitor.html

A 3.8” report from Northern Nassau and 2.9” in Plainfield, NJ.

At least a step in the right direction but the KU track still remains elusive.

The H300 PDO finished November at -2.0 due to how extensive the subsurface warmth is. https://www.cpc.ncep.noaa.gov/products/GODAS/ocean_briefing_gif/global_ocean_monitoring_current.pdf

One more Arctic outbreak before the pattern moderates.

The comparison is valid since the Saranac Lake area has warmed +5.2° since 1991 in late December between 17th and 31st. NYC is up +4.6° over the same period. Many areas have experienced a steep rise in late December temperatures. Its another one of the repeating patterns which have become a regular occurrence as the climate has warmed.

Yeah, the 100-200 year blocking event that winter as per some of the historical reconstructions was just too strong for the 75”+seasonal totals to our south to make it up to the NYC Metro era. A little weaker on the blocking and NYC could have approached the 1995-1996 all-time record. Same went for 2010-2011 which could have challenged the 75” mark around NYC had the snowy pattern persisted into February and March.

2015-2016 was a super El Niño like 1982-1983 and both years had blockbuster snowstorms during the 2nd half of winter. This was the case since El Niños usually start out slow snd have their snowiest periods later. So we often can’t use December El Niños as a marker for the rest of the season. But sometimes in the cases like 2002-2003 and 2009-2010 El Niños, December is so snowy that we get epic follow up snows during the February El Niño prime time. So in those cases a December forecast for a very snowy season would have worked out.