bluewave

Low of 37° here in SW Suffolk with the first frost of the season on the cars and rooftops.

POU finally ends its longest above freezing streak at 210 days. Number of Consecutive Days Min Temperature > 32 for Poughkeepsie Area, NY (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Run Length Dates Last value also occurred in one or more previous years. Period of record: 1931-01-01 to 2021-11-02 1 210 2021-04-07 through 2021-11-02 2 197 1942-04-15 through 1942-10-28 3 194 1971-04-25 through 1971-11-04 4 190 2007-04-22 through 2007-10-28 - 190 1975-04-23 through 1975-10-29 5 183 1990-04-20 through 1990-10-19 6 178 2016-04-16 through 2016-10-10 - 178 1946-04-19 through 1946-10-13 - 178 1944-04-20 through 1944-10-14 7 177 2018-04-24 through 2018-10-17

This is the 2nd latest first 30s at Islip. First/Last Summary for ISLIP-LI MACARTHUR AP, NY Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year Last Value First Value Difference 1971 05-05 (1971) 39 11-04 (1971) 39 182 2017 05-04 (2017) 39 11-01 (2017) 36 180 2011 05-06 (2011) 38 10-28 (2011) 37 174 1967 05-09 (1967) 38 10-26 (1967) 38 169

The EPS has a back and forth pattern also. Cool down this week followed by warm up next week. Another potential cool down showing up for the third week of November. 12z Nov 17th

The number of snow cover days held steady as temperatures and snowfall increased.

The last cold winter with memorable snowstorms was 10-11. While 13-14 and 14-15 were snowy, no one snowstorm really stood out. The lasting storm memory in 14-15 was the January snowstorm shifting east at the last minute. While 15-16 was one of our warmest winters on record, it also produced the heaviest snowstorm around NYC near 30”. The next year was almost as warm with 60s the day before the February blizzard. Although the 950 mb benchmark blizzard in January 2018 came at the end of a cold streak, the warmth in February was more impressive with our first 80°. March was the snowiest on record for Long Island. So while the last 6 winters have featured above normal to record temperatures, there has been no shortage of memorable snowstorms.

The sample size during the 1991-2020 climate normals period for measurable snow before December is small. But we have done better in seasonal snowfall when the early season measurable snow was in late November. The snowy November 2012 provides an interesting case. While we had the record early November snow, there was a smaller measurable event later that month. So the 12-13 winter did very well on snowfall further east on Long Island with Nemo record snow in February. Late October to mid November measurable snows at Newark and seasonal snowfall Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Snowfall Oct 25 to Nov 20 Seasonal Snowfall 1 2018-11-20 6.4 22.0 2 2012-11-20 6.2 29.5 Islip 46.9 3 2011-11-20 5.2 8.8 4 2007-11-20 0.4 14.6 5 1997-11-20 0.2 6.9 Late November measurable snow at Newark and seasonal snowfall Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Snowfall Nov 21 to Nov 30 Seasonal Snowfall 1 1995-11-30 3.0 78.4 2 2014-11-30 1.4 46.4 3 2002-11-30 0.6 53.1 4 2012-11-30 0.4 29.5 Islip 46.9

It will be interesting to see how long this over the top warm departure pattern lasts in the monthly means. The pattern has been locked in since last winter. Some months like October were ridiculously warmer than average in the Great Lakes and Northeast. The cooler months like last February still had a mirroring of the pattern with the record cold to the south in Texas. Temperature departures since last winter

The extended EPS and GEFS have a blocky look around Thanksgiving and possibly some early season flakes.

Not much of a change on the extended EPS from last week. Cool down for the first week of November with coldest departures remaining to our SW. Then we see a rebound in temperatures for the second week of the month. Nov 1-8 Nov 8-15

Looks like this will be the second latest freeze at POU after 1995 and 1971. They came close last week but only made it down to 34°. Posters wouldn’t mind if even a fraction of that 1995 analog worked out going forward. Frost/Freeze Summary for Poughkeepsie Area, NY (ThreadEx) Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year Last Value First Value Season Length 1995 - - 11-05 (1995) 32 - 1971 04-24 (1971) 30 11-05 (1971) 30 194 1975 04-22 (1975) 25 10-30 (1975) 31 190 2007 04-21 (2007) 32 10-29 (2007) 27 190 1942 04-14 (1942) 27 10-29 (1942) 32 197 2011 04-22 (2011) 27 10-28 (2011) 28 188 2013 05-14 (2013) 30 10-24 (2013) 31 162 2005 05-13 (2005) 32 10-24 (2005) 31 163

Interior areas could see first freeze this week with the first 30s possible closer to the coast.

Updated for October 2021 10..2021….EWR…..1…..NYC…..6…..LGA….3……..JFK……3….BDR…..3…..ISP….2

Any coastal storm next weekend will come at the time of the highest November tides with the new moon.

The 18z GFS corrected to the 12z EPS mean. 18z GFS 12z GFS

It had numerous big snows too far south like the day before the January 2016 blizzard. Also It had to come NW in the short term with the early February 2021 follow up storm.

Only the 2nd time that Newark made it to 60°every day in October. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Oct Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Max Temperature >= 60 Missing Count 1971 31 0 2021 31 0 - 2017 30 0 - 1994 30 0 - 1984 30 0 - 1947 30 0

The Euro, CMC, and GFS were similar with the track SE of MTP last Saturday and Sunday. But the Euro had the 0z run on Monday which tucked 80 miles too far west. It quickly came back to the consensus on the 12z run Monday. So one over amped run in a series of good runs isn’t that big of a deal. The main problem with its coastal storm tracks in recent years has been suppression at times. Maybe an occasional over amped run in a series of good runs means that the issue was corrected.

The GFS still is having those skill drop outs at day 5 and beyond which puts it in last place. The Euro scores increased with upgrade. So the Euro hasn’t missed any storms to suppression since the upgrade. Hopefully, this continues through the winter.

The September and October composite looks much different than 2011 and 1999. Notice how much more of a south based -NAO -AO pattern we had this year. The Northeast Pacific low was displaced south from Alaska closer to the PAC NW with the recent record storms.

One of the warmest Octobers and falls so far from the mid-Atlantic to New England. October Fall so far

Seasonal NAO and AO forecasts from the fall are notoriously difficult or the models to get right. It’s usually the weekly models that pick up on the blocking potential first. We saw this last year with the weeklies showing more and more blocking the further into November that we got. Last year was literally a one of a kind type event. We never had and El Niño 500 mb pattern with such a strong La Niña before. So the near record SPV and +NAO last November was something that we see in an El Niño year like 2015-2016. But the SPV made a dramatic reversal just as we moved into December. This November the SPV is much weaker with the near record low recently. So a much different state of the SPV. That’s probably why the weekly models continue the -NAO -AO pattern and indicate the potential for another weakening later in November. But as always, it’s a wait and see since these forecasts can change at a later time. https://ozonewatch.gsfc.nasa.gov/meteorology/wind_2021_MERRA2_NH.html Much weaker SPV November 2021 than 2020

The bouy south of the Rockaways is gusting to 50 mph. So the Shore Shore of NYC and Long Island could gust 50-60 mph next several hours. The wind gusts along the Jersey Shore are confirming the higher gusts that the 18z hi res NAM was showing.

Coastal Delaware gusting to 55 mph.