bluewave

Yeah, it still has the +PNA spike. But the SPV is a little stronger this run. So the Atlantic blocking later in November is extending north from east of New England. The last run with the weaker SPV had more Greenland blocking. But these SPV forecast beyond 10 days often change from run to run. So it may very well have another solution next week.

I think the models are going for a ridge over Western North America mid-November due to the MJO 5 La Niña standing wave. November is one of those months that convection near the Maritime Continent can force a ridge in that area. But it’s really uncertain how strong or long such a pattern would last. For later November into December, the blocking will probably determined by the strength of the SPV. And we know how uncertain these model SPV forecasts can be beyond the 6-10 day period. Our weather patterns from last November through the winter were very SPV driven. The very strong SPV in November lead to the record warmth. Then the SPV weakening was associated with the mid-December snowstorm. This was followed by record warmth on Christmas with the SPV rebound. Our best stretch of winter was in February following the major SSW.

What happens with the SPV next few weeks will probably determine how much blocking we get from later November into December.

Continuation of the colder departures further to the south theme. The departures yesterday were colder near DC than New England. We have seen this temperature departure pattern frequently this year. 11-3 departures CAR.…-2 BOS….-3 ISP…….-5 NYC…..-6 DCA……-8 Next several days more of the same Year to date temperature departures

That’s the kind of week 2 cold signal that could lead to a cold departure November if the late month blocking pattern comes to fruition.

That’s what it took to finally erase the persistent warm blob south of Alaska.

That’s one of the ways last winter was more like an El Niño. Snowy season following one of the warmest Novembers on record like 2009. We just had to wait until January for our record El Niño snows in 2015-2016. Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1975 52.7 0 2 2015 52.5 0 3 2009 51.0 0 - 2001 51.0 0 4 2020 50.9 0 - 1994 50.9 0 5 2011 50.8 0 - 2006 50.8 0 6 1948 50.7 0 7 2016 50.6 0 8 1982 50.4 0 9 1985 50.1 0

The latest first freeze at JFK was in 1983. Frost/Freeze Summary for JFK INTERNATIONAL AIRPORT, 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 Season Length 1983 03-30 (1983) 31 12-17 (1983) 31 261 1998 03-25 (1998) 31 12-14 (1998) 31 263 2016 04-10 (2016) 31 12-09 (2016) 31 242 2009 03-25 (2009) 31 12-07 (2009) 31 256 2006 04-05 (2006) 32 12-04 (2006) 31 242 1985 04-10 (1985) 29 12-02 (1985) 30 235 1975 04-07 (1975) 30 12-02 (1975) 32 238

Record lake effect snows with the warmest lake temperatures for so late in the season. RECORD EVENT REPORT NATIONAL WEATHER SERVICE 0234 AM EDT WED NOV 03 2021 ...RECORD DAILY NOVEMBER MAXIMUM SNOWFALL SET AT THE GAYLORD WEATHER FORECAST OFFICE... 11.7 INCHES BREAKS THE ALL TIME NOVEMBER DAILY SNOWFALL RECORD OF 10.7 INCHES SET BACK ON NOVEMBER 18TH, 2014. THIS IS ALSO THE 6TH HIGHEST ONE DAY TOTAL SNOWFALL FOR THE GAYLORD WEATHER FORECAST OFFICE SINCE RECORDS BEGAN BACK IN 1998.

2015-2016 was even more extreme at LGA. It was their only first freeze of the season to occur in January. Then it was followed by their biggest snowstorm on record. Frost/Freeze Summary for LAGUARDIA AIRPORT, 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 Season Length 2015 03-29 (2015) 27 01-04 (2016) 15 280 2001 03-28 (2001) 31 12-23 (2001) 32 269 1998 03-22 (1998) 31 12-22 (1998) 24 274 2011 03-29 (2011) 32 12-11 (2011) 31 256 1948 04-10 (1948) 32 12-11 (1948) 32 244 Maximum 3-Day Total Snowfall for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days Period of record: 1940-01-01 to 2021-11-02 1 28.2 2016-01-25 0 - 28.2 2016-01-24 0 27.9 2016-01-23 0 2 25.4 2006-02-13 0 - 25.4 2006-02-12 0 3 24.2 1996-01-09 0 23.8 1996-01-08 0 23.3 2006-02-14 0 4 22.8 1947-12-28 0 - 22.8 1947-12-27 0

Gorgeous photos of the sea smoke on the Long Island Sound with the SSTs still in the low 60s.

Places that miss their first freeze this week will get another chance mid-November as the trough returns to the East.

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