November 2020 General Discussions & Observations Thread

[bluewave]

Just now, snowman19 said:

Very flat Aleutian ridge, +EPO, +NAO, not good signs going into early December 

Very tough to get any extended cold with such a fast Pacific flow. Notice how we get cold for a few days following the Great Lakes lows. But the +EPO, +NAO, and SSTs allow a quick warm up and the SE Ridge flexes again. 

 

 

[donsutherland1]

Morning thoughts...

Today will be mostly sunny but cool. High temperatures in the region will likely reach mainly the lower and middle 50s. Likely high temperatures around the region include:

New York City (Central Park): 52°

Newark: 54°

Philadelphia: 55°

A cold front will move across the region during the latter part of tomorrow afternoon or during the evening. The frontal passage could be marked by a squall line with thunder, a brief period of heavy rain and wind gusts in excess of 40 mph. Tuesday through Thursday will be unseasonably cold. 

[MJO812]

12 hours ago, JoshSnow said:

Gfs showing some blocking by the end of November and potentially getting a bit colder with some snow chances finally.

0z gfs has a snowstorm for the area but it's gone in the 6z GFS. The euro has a nice cold dump at 240. 

Maybe we can get lucky at the end of the month  

[MJO812]

1 hour ago, bluewave said:

The late November pattern looks similar to recent winters. Very fast Pacific flow and +EPO. The -AO blocking doesn’t look  strong enough to eliminate the SE Ridge as the +NAO vortex holds on. So the primary storm track will remain through the Great Lakes. Ridges persist over the warm Atlantic and Pacific SST band along 40N.

 

 

 

This isnt bad at all.  Just need the ridge in the east to relax a bit. 

[bluewave]

30 minutes ago, MJO812 said:

This isnt bad at all.  Just need the ridge in the east to relax a bit. 

The SE Ridge has only relaxed for 3 out of the last 15 DJF met winter months. The 3 winter  months it hasn’t been a factor since the 15-16 winter were Dec 17, Feb 16, and Jan 16. We should probably develop a SE Ridge or WAR index like the other teleconnections since it has become such a dominant feature of our recent climate.

[snowman19]

1 hour ago, MJO812 said:

This isnt bad at all.  Just need the ridge in the east to relax a bit. 

How is that a good look?  The EPO floodgates are wide open. All you are getting is Pacific maritime air, the NAO is positive to boot, even if it wasn’t and went negative with that PAC look, all it would do is bring down garbage Pacific air

[Brian5671]

2 hours ago, MJO812 said:

This isnt bad at all.  Just need the ridge in the east to relax a bit. 

No cold air anywhere though

[jm1220]

3 hours ago, MJO812 said:

This isnt bad at all.  Just need the ridge in the east to relax a bit. 

The trough over Alaska floods the US with Pacific air. Maybe it’ll be a little less of a torch? But certainly not below normal 

[jm1220]

5 hours ago, bluewave said:

The late November pattern looks similar to recent winters. Very fast Pacific flow and +EPO. The -AO blocking doesn’t look  strong enough to eliminate the SE Ridge as the +NAO vortex holds on. So the primary storm track will remain through the Great Lakes. Ridges persist over the warm Atlantic and Pacific SST band along 40N.

 

 

 

So much for -AO typically meaning -NAO. The last few winters have done away with that correlation. 

[LongBeachSurfFreak]

48 minutes ago, jm1220 said:

So much for -AO typically meaning -NAO. The last few winters have done away with that correlation. 

Throw out the analogs. There are enough differences from the last two winters to offer some hope that we at least break the streak of no 6” or greater storms for the coast. The last two winters were epic fails south of the southern state.

[bluewave]

1 hour ago, jm1220 said:

So much for -AO typically meaning -NAO. The last few winters have done away with that correlation. 

Yeah, we have seen several -AO/+NAO splits in recent years. This wasn’t the case for the 09-10 and 10-11 winters. Notice how much different the DJF winter SSTs have been since 13-14. Much warmer SSTs off the East Coast and a cold pool south of Greenland. 
 

 

[snowman19]

1 hour ago, bluewave said:

Yeah, we have seen several -AO/+NAO splits in recent years. This wasn’t the case for the 09-10 and 10-11 winters. Notice how much different the DJF winter SSTs have been since 13-14. Much warmer SSTs off the East Coast and a cold pool south of Greenland. 
 

 

An AO/NAO disconnect isn’t going to help us with a PAC that looks like what the models are depicting in the long range now. You need both a very deeply negative AO and west-based -NAO to compensate for that disaster 

[LibertyBell]

7 hours ago, bluewave said:

The SE Ridge has only relaxed for 3 out of the last 15 DJF met winter months. The 3 winter  months it hasn’t been a factor since the 15-16 winter were Dec 17, Feb 16, and Jan 16. We should probably develop a SE Ridge or WAR index like the other teleconnections since it has become such a dominant feature of our recent climate.

In the 15-16 winter we didn't have a SE Ridge in either Jan 16 or Feb 16?  Should've done better with snowfall than just the one HECS we got.

 

[LibertyBell]

9 hours ago, bluewave said:

Very tough to get any extended cold with such a fast Pacific flow. Notice how we get cold for a few days following the Great Lakes lows. But the +EPO, +NAO, and SSTs allow a quick warm up and the SE Ridge flexes again. 

 

 

This is the very familiar late 80s early 90s type pattern we've been getting the last few winters.

[LibertyBell]

7 hours ago, bluewave said:

The SE Ridge has only relaxed for 3 out of the last 15 DJF met winter months. The 3 winter  months it hasn’t been a factor since the 15-16 winter were Dec 17, Feb 16, and Jan 16. We should probably develop a SE Ridge or WAR index like the other teleconnections since it has become such a dominant feature of our recent climate.

This is a very stable pattern and I would go so far as to say this is the dominant weather pattern for our area (the one that lasts the longest).  In all my years on the east coast that I can remember, going back to the early 80s.....this is the pattern that recurs more often than any other.

 

[LibertyBell]

3 hours ago, LongBeachSurfFreak said:

Throw out the analogs. There are enough differences from the last two winters to offer some hope that we at least break the streak of no 6” or greater storms for the coast. The last two winters were epic fails south of the southern state.

Well in my experience not getting 6"+ snowstorms have happened in the majority of winters.

If you want to be optimistic, the best we can hope for is one big snowstorm for the winter and that's it.

[LibertyBell]

1 hour ago, snowman19 said:

An AO/NAO disconnect isn’t going to help us with a PAC that looks like what the models are depicting in the long range now. You need both a very deeply negative AO and west-based -NAO to compensate for that disaster 

The funny thing about the PAC is with the string of bad winters we've had, you'd expect a city in the NW like Seattle to be cashing in, but they've been in a long term snow drought (much longer than ours.)

 

[the_other_guy]

3 hours ago, LongBeachSurfFreak said:

Throw out the analogs. There are enough differences from the last two winters to offer some hope that we at least break the streak of no 6” or greater storms for the coast. The last two winters were epic fails south of the southern state.

It’s not just southern Long Island.

My parents are in Queens and I’m their  snow shovel guy.

I haven’t lifted a snow shovel for them in 2 years.

Everything was either too small or melted in quick order

[the_other_guy]

16 minutes ago, LibertyBell said:

This is a very stable pattern and I would go so far as to say this is the dominant weather pattern for our area (the one that lasts the longest).  In all my years on the east coast that I can remember, going back to the early 80s.....this is the pattern that recurs more often than any other.

 

Good point. It is just happening with a much warmer regime now.

For a city that was always on a rain/snow line and never locked in wall to wall cold like a midwestern city, that is the death blow

The relentless big storm phenomenon was a recent addition, and now subtraction

[LibertyBell]

4 minutes ago, jfklganyc said:

Good point. It is just happening with a much warmer regime now.

For a city that was always on a rain/snow line and never locked in wall to wall cold like a midwestern city, that is the death blow

The relentless big storm phenomenon was a recent addition, and now subtraction

6" snowfall might be a good dividing line.

I read in the Weather Almanac that NYC gets a 6" snowstorm in 50% of its winters and a 8" snowstorm in 33% of them.

 

[bluewave]

32 minutes ago, LibertyBell said:

This is the very familiar late 80s early 90s type pattern we've been getting the last few winters.

The last 2 met winters were the first consecutive under 5” DJFs for NYC. After 09-10 to 17-18, I don’t think anyone would have made that bet. Just goes to show how extreme our climate has become.

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Rank	Season	Total Snowfall	Missing Count
1	1997-1998	0.5	0
2	1918-1919	1.1	0
3	1972-1973	2.6	0
4	1931-1932	2.7	0
5	1991-1992	3.2	0
6	2001-2002	3.5	0
7	2018-2019	3.7	0
8	2011-2012	4.5	0
9	2019-2020	4.8	0
10	1989-1990	5.0	0

[LibertyBell]

12 minutes ago, bluewave said:

The last 2 met winters were the first consecutive under 5” DJFs for NYC. After 09-10 to 17-18, I don’t think anyone would have made that bet. Just goes to show how extreme our climate has become.

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Rank	Season	Total Snowfall	Missing Count
1	1997-1998	0.5	0
2	1918-1919	1.1	0
3	1972-1973	2.6	0
4	1931-1932	2.7	0
5	1991-1992	3.2	0
6	2001-2002	3.5	0
7	2018-2019	3.7	0
8	2011-2012	4.5	0
9	2019-2020	4.8	0
10	1989-1990	5.0	0

Wasnt the period between 83-84 to about 91-92 much less snowy though?

Also what about 96-97 to about 99-00?

edit- in that list I see that 89-90 to 91-92 had 2/3 that were 5.0 or below.  I put that in the HOF of least snowiest because of how snowless the 70s and 80s generally were.

Also look at 97-98 to 01-02 which had 2 that were 3.5 or lower (that streak was broken up by 00-01 though which was a decent winter with the Millenium storm).

 

[bluewave]

10 minutes ago, LibertyBell said:

Wasnt the period between 83-84 to about 91-92 much less snowy though?

Also what about 96-97 to about 99-00?

 

Only 79-80, 88-89, and 89-90 finished DJF with single digits. During the 90s it was 91-92, 96-97 , 97-98, and 98-99.

 

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1979-1980	8.2	0
1980-1981	10.8	0
1981-1982	14.3	0
1982-1983	26.4	0
1983-1984	13.5	0
1984-1985	23.9	0
1985-1986	13.0	1
1986-1987	21.2	0
1987-1988	18.0	0
1988-1989	5.6	0
1989-1990	5.0	0

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1990-1991	24.7	0
1991-1992	3.2	0
1992-1993	12.6	0
1993-1994	45.3	0
1994-1995	11.8	0
1995-1996	58.8	0
1996-1997	8.2	0
1997-1998	0.5	0
1998-1999	8.2	0
1999-2000	14.7	0

 

[LibertyBell]

1 minute ago, bluewave said:

Only 79-80, 88-89, and 89-90 finished DJF with single digits.

 

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1979-1980	8.2	0
1980-1981	10.8	0
1981-1982	14.3	0
1982-1983	26.4	0
1983-1984	13.5	0
1984-1985	23.9	0
1985-1986	13.0	1
1986-1987	21.2	0
1987-1988	18.0	0
1988-1989	5.6	0
1989-1990	5.0	0

Chris, what about 91-92?  It was in your list (and pretty high up!) in the previous post.

 

[bluewave]

Just now, LibertyBell said:

Chris, what about 91-92?  It was in your list (and pretty high up!) in the previous post.

 

I added it.

[LibertyBell]

2 minutes ago, bluewave said:

Only 79-80, 88-89, and 89-90 finished DJF with single digits.

 

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1979-1980	8.2	0
1980-1981	10.8	0
1981-1982	14.3	0
1982-1983	26.4	0
1983-1984	13.5	0
1984-1985	23.9	0
1985-1986	13.0	1
1986-1987	21.2	0
1987-1988	18.0	0
1988-1989	5.6	0
1989-1990	5.0	0

so wow I do have the right to brag that when I was in HS I experienced the least snowy period in NYC history..... 88-89, 89-90 and 91-92 all had 5.6 or less inches of snow!  I wonder what happened to 90-91, how much in that season Chris?

 

[bluewave]

6 minutes ago, LibertyBell said:

so wow I do have the right to brag that when I was in HS I experienced the least snowy period in NYC history..... 88-89, 89-90 and 91-92 all had 5.6 or less inches of snow!  I wonder what happened to 90-91, how much in that season Chris?

 

The big low snowfall record left for NYC is a DJF or full snowfall season T.  On the high side, NYC still hasn’t seen a 50” single storm in the modern era. A 10” in one hour would be another snowfall extreme we are yet to see. We should take bets on which of those 3 happens first.

[LibertyBell]

7 minutes ago, bluewave said:

Only 79-80, 88-89, and 89-90 finished DJF with single digits. During the 90s it was 91-92, 96-97 , 97-98, and 98-99.

 

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1979-1980	8.2	0
1980-1981	10.8	0
1981-1982	14.3	0
1982-1983	26.4	0
1983-1984	13.5	0
1984-1985	23.9	0
1985-1986	13.0	1
1986-1987	21.2	0
1987-1988	18.0	0
1988-1989	5.6	0
1989-1990	5.0	0

Time Series Summary for NY CITY CENTRAL PARK, NY - Dec through Feb
Click column heading to sort ascending, click again to sort descending.

Season	Total Snowfall	Missing Count
1990-1991	24.7	0
1991-1992	3.2	0
1992-1993	12.6	0
1993-1994	45.3	0
1994-1995	11.8	0
1995-1996	58.8	0
1996-1997	8.2	0
1997-1998	0.5	0
1998-1999	8.2	0
1999-2000	14.7	0

 

This is a GREAT snapshot of the 80s and 90s, Chris- the first time I've seen someone do something like this.

So in a nutshell there were two periods devoid of meaningful snowfall.

One was 88-89 to 91-92 (with the exception of 90-91) 3 out of 4 winters with 5.6 inches or less of snow.

Then we have the sequel:

96-97 to 01-02 (with the exceptions of 99-00 and 00-01) with 3 in a row with 8.2 inches or less of snow and 4 out of 6 with 8.2 or less inches of snow because I'm going to include 01-02 since it was the warmest winter I've ever experienced and just as historic as 95-96 was in the other direction.  To have 97-98 and 01-02 in the same stretch was truly horrendous. On the other hand we can't complain since we also had 93-94 and 95-96 in (50"+ winters) 2 out of 3 winters or 02-03 to 05-06 (40"+ winters) 4 straight or 09-10 or 10-11 (50"+ winters) back to back or 13-14 and 14-15 (50"+ winters) back to back and 3 straight (40"+ winters) if you also include the JFK total in 15-16.  By the way please double check my numbers since I'm doing this off the top of my head.  And can you do a list for the 2010s decade also please (I want to see how feast or famine we've been over the last 10 years.)

 

[LibertyBell]

28 minutes ago, bluewave said:

The big low snowfall record left for NYC is a DJF or full snowfall season T.  On the high side, NYC still hasn’t seen a 50” single storm in the modern era. A 10” in one hour would be another snowfall extreme we are yet to see. We should take bets on which of those 3 happens first.

number 1 most likely T for DJF (almost did it in 97-98) hands down.

Um I've having a tough time trying to decide between 50" single storm and 10" in one hour, they both seem highly unlikely but I guess it can happen since Nemo Feb 2013 came close to both of those numbers in parts of CT and LI?  At any rate at least I've seen 30" in one storm (Jonas Jan 2016.)

I'll add another couple, what about 100" total snowfall for the year and 60" in one month (averaging 2" per day over a 30 day month). 100" total snowfall for a 12 month period I think we either did it or came close if you go from Dec 09 to Dec 10 and maybe also Dec 02 to Dec 03?  60" over a 30 day period we might have come close (parts of LI definitely did it) between Dec 10 and Jan 11?  That was the snowiest stretch as well as the longest duration snowcover I've ever experienced on the south shore (from the day after Christmas to Valentine's Day!)  That winter truly turned on a dime, before Boxing Day we were talking about a paltry winter because of the La Nina which was moderate to strong and by the end of that period we were using analogs from the 1910s which was the last time NYC had such a snowy and cold moderate to strong La Nina and also the last time NYC had back to back 50"+ snowfall seasons (1916-17 and 1917-18) until 2009-10 and 2010-11.  It could have been our snowiest winter of all time if the party didn't abruptly stop in February lol.  Very similar to 1960-61 in that respect.  And then we had another 50"+ consecutive snowfall seasons in 13-14 and 14-15 (which makes the 2010s decade truly amazing- even moreso than the 4 straight 40"+ snowfall seasons from 02-03 to 05-06).  Feb/Mar backend in 2014-15 was also amazing, similar to what we got in 1966-67.

 

 

 

[bluewave]

17 minutes ago, LibertyBell said:

This is a GREAT snapshot of the 80s and 90s, Chris- the first time I've seen someone do something like this.

So in a nutshell there were two periods devoid of meaningful snowfall.

One was 88-89 to 91-92 (with the exception of 90-91) 3 out of 4 winters with 5.6 inches or less of snow.

Then we have the sequel:

96-97 to 01-02 (with the exceptions of 99-00 and 00-01) with 3 in a row with 8.2 inches or less of snow and 4 out of 6 with 8.2 or less inches of snow because I'm going to include 01-02 since it was the warmest winter I've ever experienced and just as historic as 95-96 was in the other direction.  To have 97-98 and 01-02 in the same stretch was truly horrendous. On the other hand we can't complain since we also had 93-94 and 95-96 in (50"+ winters) 2 out of 3 winters or 02-03 to 05-06 (40"+ winters) 4 straight or 09-10 or 10-11 (50"+ winters) back to back or 13-14 and 14-15 (50"+ winters) back to back and 3 straight (40"+ winters) if you also include the JFK total in 15-16.  By the way please double check my numbers since I'm doing this off the top of my head.  And can you do a list for the 2010s decade also please (I want to see how feast or famine we've been over the last 10 years.)

 

Yeah, 93-94 and 95-96 were our only high snowfall seasons from 79-80 to 99-00.

 

Time Series Summary for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Ending Date	Total Snowfall Oct 1 to Apr 30	Missing Count
1980-04-30	12.8	0
1981-04-30	19.4	0
1982-04-30	24.6	0
1983-04-30	27.2	0
1984-04-30	25.4	0
1985-04-30	24.1	0
1986-04-30	13.0	1
1987-04-30	23.1	0
1988-04-30	19.1	0
1989-04-30	8.1	0
1990-04-30	13.4	0
1991-04-30	24.9	0
1992-04-30	12.6	0
1993-04-30	24.5	0
1994-04-30	53.4	0
1995-04-30	11.8	0
1996-04-30	75.6	0
1997-04-30	10.0	0
1998-04-30	5.5	0
1999-04-30	12.7	0
2000-04-30	16.3	0