December 2021

[SnoSki14]

EPS looked better tonight. WPO & AO/NAO looked good however I would still rather be in New England than here for snows/cold. 

[donsutherland1]

Morning thoughts…

Today will be mostly sunny, breezy, and mild. High temperatures will likely reach the lower and middle 50s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 53°

Newark: 55°

Philadelphia: 57°

Normals:

New York City: 30-Year: 44.9°; 15-Year: 45.6°

Newark: 30-Year: 45.4°; 15-Year: 46.2°

Philadelphia: 30-Year: 46.6°; 15-Year: 47.5°

The unseasonably mild weather will continue into the start of the weekend.

[bluewave]

We are on track for a top 10 warmest first half of December across the area. Between 6 out of the 8 top 10 warmest years occurred since the late 90s. So with the new warmer December climate normals, the stations did this with a +4 to +5 departure.

EWR….+5.4

ISP…….+3.8

LGA……+4.2

 

Time Series Summary for NEWARK LIBERTY INTL AP, NJ
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Dec 13	Missing Count
1	1998-12-13	50.6	0
2	2001-12-13	50.0	0
3	2015-12-13	49.2	0
4	1951-12-13	45.9	0
5	2021-12-13	45.7	0
-	1953-12-13	45.7	0
6	2012-12-13	44.8	0
7	1982-12-13	44.3	0
8	1999-12-13	44.2	0
-	1991-12-13	44.2	0
9	1973-12-13	43.7	0
10	1993-12-13	43.5	0

 

Time Series Summary for ISLIP-LI MACARTHUR AP, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Dec 13	Missing Count
1	1998-12-13	48.1	0
2	2015-12-13	47.7	0
3	2001-12-13	46.5	0
4	2012-12-13	43.8	0
5	1972-12-13	43.6	0
6	1991-12-13	43.5	0
7	2021-12-13	43.1	0
8	2004-12-13	42.0	0
9	1999-12-13	41.9	0
10	2011-12-13	41.6	0

 

Time Series Summary for LAGUARDIA AIRPORT, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Dec 13	Missing Count
1	1998-12-13	52.9	0
2	2001-12-13	51.7	0
3	2015-12-13	50.9	0
4	1953-12-13	48.2	0
5	1951-12-13	47.5	0
6	2021-12-13	46.7	0
7	2012-12-13	46.3	0
8	1991-12-13	45.9	0
9	1999-12-13	45.8	0
10	1948-12-13	45.5	0

[CIK62]

The next 8 days are averaging. 45degs.(41/50), or +9---+6 nowadays.

Month to date is  44.9[+3.5].       Should be near 44.9[+4.5] by the 22nd.

Reached 53 here yesterday.

Today:  50-53, wind n. to e., m. clear.     GFS cold by year's end?  10" Snow again---this time on the 27th.     The dog has begun to chase his tail perhaps?

45*(45%RH) here at 6am.   46* at 7am.     51* at Noon.      55* at 3pm.      48* at 11pm.    

[MJO812]

3 hours ago, SnoSki14 said:

EPS looked better tonight. WPO & AO/NAO looked good however I would still rather be in New England than here for snows/cold. 

Still trending

I think we will be fine

[MJO812]

Gfs is way south at 6z for the 21st

Eps doesn't look bad at all

[MJO812]

Can this trend in our favor or do we want this little storm to trend north so the big storm is also north ?

 

[lee59]

Heat island in full affect this morning. NYC at 46 degrees while many suburbs in the 20s to mid 30s. 32 degrees here.

[MJO812]

6 minutes ago, lee59 said:

Heat island in full affect this morning. NYC at 46 degrees while many suburbs in the 20s to mid 30s. 32 degrees here.

NYC is an awful place to live for winter weather.

[EasternLI]

That ~22nd thing gaining support from the EPS. Gotta watch the trends with this. This is what the top two EPS clusters are looking like from today's 00Z. Eyes open today. 

Hr 192

[rclab]

19 minutes ago, MJO812 said:

NYC is an awful place to live for winter weather.

Good morning Anthony. Rather than to experience it, NYC is a great place to appreciate winter weather. As we turn briefly away from our warm significant other to our east, we look wistfully through a gradient driven toy store window to our west/north west/ north and north east as we “per chance” continue to dream. As always …..

[lee59]

3 minutes ago, rclab said:

Good morning Anthony. Rather than to experience it, NYC is a great place to appreciate winter weather. As we turn briefly away from our warm significant other to our east, we look wistfully through a gradient driven toy store window to our west/north west/ north and north east as we “per chance” continue to dream. As always …..

It's all perspective. People that love snow and live in the Carolinas would love to live in NYC or any of its suburbs. People in Vermont, not so much.

[Allsnow]

[Allsnow]

[MJO812]

2 minutes ago, Allsnow said:

NAO goes negative and stays negative for the rest of the month on the eps starting at the end of this week.

[LoboLeader1]

38* here this AM. 

[EastonSN+]

14 hours ago, bluewave said:

No recent years going into January had anything close to that 500 mb pattern. The only January with such a prominent -EPO/-PNA/-NAO was 1969. FWIW,  NYC finished at 31.8°, 1.10” of precipitation, and only 1.0” of snow. It was a very dry month. The caveats are that the extended EPS is only just a snapshot of what it’s showing from the end of December into early January. Skill falls off beyond the 2nd week.

 

Thanks again for the above.

The ensembles seem to have the NAO further north than the above, and the RNA a little more east/onshore. Perhaps this will lead to more precip? 

In any case it's exciting to see a pattern not experienced since 69! 

February 69 had one of the best blizzards of all time, perhaps as the blocking relaxes we experience something similar.

[bluewave]

16 minutes ago, EastonSN+ said:

Thanks again for the above.

The ensembles seem to have the NAO further north than the above, and the RNA a little more east/onshore. Perhaps this will lead to more precip? 

In any case it's exciting to see a pattern not experienced since 69! 

February 69 had one of the best blizzards of all time, perhaps as the blocking relaxes we experience something similar.

If the -NAO blocks have been strong enough over the last 10 years, they have usually been able to retrograde back to the PNA region. So what the models are showing now is something different with a strong -PNA and -NAO. It’s probably related to the record NEPAC vortex since the fall. Plus the ensemble effective range is only about 2 weeks. So we are just seeing a brief model snapshot. The actual pattern will likely vary away from what may or may not look like a match from the past. Most analog matches usually occur after the fact. That’’s why using specific analogs well before the new month starts rarely works out.

[LibertyBell]

1 hour ago, bluewave said:

The new 91-20 climate normals seasonal snowfall in NYC is 29.8”. NYC has never reached 30.0” in a La season with under 3.0” in December since 1950. This must be related to the fact that the good La Niña years for snowfall get off to an early start since they are front-loaded.

NYC December snowfall during La Ninas and seasonal snowfall.

2017…..7.7….40.9

2016….3.2….30.2

2011…..0.0….7.4

2010….20.1….61.9

2008….6.0…..27.6

2007….2.9……11.9

2005….9.7……40.0

2000….13.4…..35.0

1999…….T…….16.3

1998…..2.0……12.7

1995…..11.5…..75.6

1988…..0.3……8.1

1984…..5.5…..24.1

1975…..2.3…..17.3

1974……0.1…..13.1

1973…..2.8….23.5

1971…….T……22.9

1970……2.4….15.5

1964……3.1….24.4

1955…...3.3…33.5

1954…...0.1….11.5

1949……1.5….14.0

But by random, the site location could also make it random since you can't make the same correlation with JFK for example.  So a random band of snow could've parked itself over Central Park to get it to 3" and it didn't happen at nearby official measuring sites.  If you made the same list for JFK, how closely does it match the above vs their average seasonal snowfall?  Also shouldn't 2020-21 be on this list since that was a La Nina we had last year?

 

 

[LibertyBell]

16 minutes ago, bluewave said:

If the -NAO blocks have been strong enough over the last 10 years, they have usually been able to retrograde back to the PNA region. So what the models are showing now is something different with a strong -PNA and -NAO. It’s probably related to the record NEPAC vortex since the fall. Plus the ensemble effective range is only about 2 weeks. So we are just seeing a brief model snapshot. The actual pattern will likely vary away from what may or may not look like a match from the past. Most analog matches usually occur after the fact. That’’s why using specific analogs well before the new month starts rarely works out.

Can the -NAO/-AO be strong enough to knock down the -PNA?  I thought it's best to use analogs starting around the 20th of the previous month?

[SnoSki14]

57 minutes ago, bluewave said:

New England may end up winning the gradient battle in late December like they often do. Also notice  how the coldest air is remaining near Montana. We have seen this many times in recent years.

 

 

 

Which is why I can't see us doing well in this pattern. That -PNA is a death knell for this time of year.

-PNA is better for us after mid Feb. when wavelengths change.

S/C New England should do well though. 

[donsutherland1]

20 minutes ago, LibertyBell said:

But by random, the site location could also make it random since you can't make the same correlation with JFK for example.  So a random band of snow could've parked itself over Central Park to get it to 3" and it didn't happen at nearby official measuring sites.  If you made the same list for JFK, how closely does it match the above vs their average seasonal snowfall?  Also shouldn't 2020-21 be on this list since that was a La Nina we had last year?

 

 

We had more than 3” of snow in December 2020.

[bluewave]

45 minutes ago, LibertyBell said:

But by random, the site location could also make it random since you can't make the same correlation with JFK for example.  So a random band of snow could've parked itself over Central Park to get it to 3" and it didn't happen at nearby official measuring sites.  If you made the same list for JFK, how closely does it match the above vs their average seasonal snowfall?  Also shouldn't 2020-21 be on this list since that was a La Nina we had last year?

 

 

I left off last winter since the La Niña never coupled. But you can use it if you want. NYC had a snowy December and it was reflected in the seasonal totals coming in above normal. The La Niña relationship holds for JFK also. Under the 25.9” seasonal normal  if they get under 3.0” in December during a La Niña.

2017….6.7….35.5

2016….3.3…30.9

2011…..0.0….3.7

2010….15.8….42.0

2008….4.9…..22.3

2007….2.4……11.7

2005….5.0…..25.4

2000….11.9…..33.8

1999….0.1……14.1

1998….2.3…..12.3

1995….10.5…69.0

1988…..0.7….8.2

1984….5.5….27.3

1983…..1.2…..22.0

 

[EasternLI]

 

[MJO812]

34 minutes ago, LibertyBell said:

the concrete needs to be torn up

 

Yes sir

34 minutes ago, SnoSki14 said:

Which is why I can't see us doing well in this pattern. That -PNA is a death knell for this time of year.

-PNA is better for us after mid Feb. when wavelengths change.

S/C New England should do well though. 

You are missing the NAO, AO and EPO.

[MJO812]

1 hour ago, Allsnow said:

Why is Bluewave giving you a weenie for posting the eps?

[MJO812]

6 minutes ago, EasternLI said:

 

Hopefully the weeklies are right

If so then we will have plenty of chances in the upcoming weeks.

[bluewave]

4 minutes ago, MJO812 said:

Why is Bluewave giving you a weenie for posting the eps?

Just returning the favor for him giving the weenie to my earlier post.

[rclab]

4 minutes ago, bluewave said:

Just returning the favor for him giving the weenie to my earlier post.

Where else, other than on our weather forums, could a weenie be given courteously. As always ……

[psv88]

29 this morning