December 2021

[bluewave]

42 minutes ago, jm1220 said:

Sometimes I wish we could accelerate continental drift and close the Pacific off. 

Multiple 5 sigma North Pacific and East Asian Jet maxes is as extreme as it gets to start December. This really pumps the ridge out near the Dateline and Aleutians. So it keeps reinforcing the +EPO -PNA pattern. The Atlantic is of no help at this time with a strong +AO +NAO pattern.

 

 

[MJO812]

We might have a brief window around the 8th where we might be able to capitalize .

[StormchaserChuck!]

Pretty sure we'll bein the 50s/60s consistently. 

[bluewave]

We have gotten used to the +PDO La Niña Decembers of recent years. But the December La Niña composite with a strong -PDO features a strong Aleutians Ridge like the models are advertising. This creates more of +EPO and -PNA pattern in December. The near record warm Atlantic SSTs will enhance the Southeast Ridge by mid-December. 

 

 

[snowman19]

25 minutes ago, bluewave said:

We have gotten used to the +PDO La Niña Decembers of recent years. But the December La Niña composite with a strong -PDO features a strong Aleutians Ridge like the models are advertising. This creates more of +EPO and -PNA pattern in December. The near record warm Atlantic SSTs will enhance the Southeast Ridge by mid-December. 

 

 

We got lucky with the +PDO Nina’s since 2000. This year….different story. Also great point about those torched SSTs along and off the coast. They are just going to feedback into the SE Ridge/WAR

[Stormlover74]

Already 50 at ewr...above the forecast high 

[donsutherland1]

New York City's mean monthly temperature fell from 62.0° to 46.2°, a change of 15.8°. That change was 1.315 sigma above the historic (1869-2020) October-November change. Such an outcome has often precluded a severely cold December.

The historic November-December change is 10.2°. The 23 cases with a 1 sigma or greater change above the October-November average saw an average 7.8° change in temperature during the November-December timeframe. In 65% of the cases, the change was smaller than the normal change. In 35% of cases, the change was 1 sigma or more below the historic November-December change. All of those 1 sigma cases would imply a December mean temperature of 40° or above. The change was 0.5 sigma or more above the historic November-December change in just 13% of the cases.

The most recent year that saw a 1 sigma or more change from the historic October-November change was 2019. In December, the temperature fell 5.6° from November to 38.3°.

In terms of seasonal snowfall, a larger than normal decline in the November-December period for the 1 sigma October-November cases was snowier than the more typical smaller decline.

Smaller November-December Temperature Change:

Mean Seasonal Snowfall: 23.5"
Median Seasonal Snowfall: 19.7"

Distribution:
40" or more:  13%
30" or more: 27%
20" or more: 47%
< 20": 53%
< 10": 7%

Least: 4.8", 2019-20
Most: 57.4", 2013-14

n=15

Larger November-December Temperature Change:

Mean Seasonal Snowfall: 39.0"
Median Seasonal Snowfall: 32.9"

Distribution:
40" or more:  38%
30" or more: 63%
20" or more: 75%
< 20": 25%
< 10": 13%

Least: 11.5", 1954-55
Most: 75.6", 1995-96

n=8

 

[Eduardo]

2 hours ago, MJO812 said:

A moderator who weenies people 

What a guy

It's all outta love, man!

[Eduardo]

1 hour ago, bluewave said:

We have gotten used to the +PDO La Niña Decembers of recent years. But the December La Niña composite with a strong -PDO features a strong Aleutians Ridge like the models are advertising. This creates more of +EPO and -PNA pattern in December. The near record warm Atlantic SSTs will enhance the Southeast Ridge by mid-December. 

 

 

Honestly, it's looking pretty dismal for the next few weeks (and possibly beyond) unless we manage to get some ATL blocking.  True, it's only December 1st, but I'd really like to see this turn around sooner than later.  I mean, that's about as bad a look as you can ask for if you like cold and snow.

[bluewave]

46 minutes ago, snowman19 said:

We got lucky with the +PDO Nina’s since 2000. This year….different story. Also great point about those torched SSTs along and off the coast. They are just going to feedback into the SE Ridge/WAR

Those record warm Atlantic SSTs and the faster Pacific Jet allowed the ridge over our area to verify stronger than forecast today.

Verification already 50° at Newark

 

Old forecast was colder for today

 

 

Record warm Atlantic SSTs

https://mco.umaine.edu/gom_sst/

 

 

 

[MJO812]

Negative epo presses more on the gefs. Have to watch out for that for the storm near the 10th.

[snowman19]

24 minutes ago, bluewave said:

Those record warm Atlantic SSTs and the faster Pacific Jet allowed the ridge over our area to verify stronger than forecast today.

Verification already 50° at Newark

 

Old forecast was colder for today

 

 

Record warm Atlantic SSTs

https://mco.umaine.edu/gom_sst/

 

 

 

We currently have one of the strongest ENSO standing waves on record: 

 

[snowman19]

13 minutes ago, MJO812 said:

Negative epo presses more on the gefs. Have to watch out for that for the storm near the 10th.

Interior northern New England may get something out of it…..

[MJO812]

44 minutes ago, snowman19 said:

Interior northern New England may get something out of it…..

Depends if we can get the Baroclinic line to drop south of our area

[Stormlover74]

Ewr just jumped 7 degrees in 1 hour. Something has to be off

[forkyfork]

Just now, Stormlover74 said:

Ewr just jumped 7 degrees in 1 hour. Something has to be off

i don't want to give fodder to the usual suspects but something is definitely wrong with the sensor now

[Brian5671]

50 here as well-above Upton's forecast

[bluewave]

The Central Park leaves that were blocking the ASOS may have finally begun to drop.  It’s near 50° now like JFK and LGA.  All the stations are warmer than high temperature guidance today.
 

000
SXUS51 KOKX 011757
OSOOKX
New York City Metropolitan Area Weather Roundup
National Weather Service New York NY
100 PM EST WED DEC 01 2021

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
Central Park   MOSUNNY   49  24  37 VRB5      30.16F
LaGuardia Arpt PTSUNNY   49  23  36 NW12      30.14F
Kennedy Intl   PTSUNNY   49  25  39 W14       30.16F

 

 

[Superstorm]

The Central Park leaves that were blocking the ASOS may have finally begun to drop.  It’s near 50° now like JFK and LGA.  All the stations are warmer than high temperature guidance today.
 

000SXUS51 KOKX 011757OSOOKXNew York City Metropolitan Area Weather RoundupNational Weather Service New York NY100 PM EST WED DEC 01 2021CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKSCentral Park   MOSUNNY   49  24  37 VRB5      30.16FLaGuardia Arpt PTSUNNY   49  23  36 NW12      30.14FKennedy Intl   PTSUNNY   49  25  39 W14       30.16F

 
 

So cool to see that.


.

[Tatamy]

2 hours ago, MJO812 said:

Negative epo presses more on the gefs. Have to watch out for that for the storm near the 10th.

Fair amount of interest out there on the models today for this one especially from the city on to the north and west.  The CMC / Euro have this one along with 7 members of the GEFS.  This is by no means anything overly significant however it is something to watch.  

[snowman19]

3 hours ago, bluewave said:

Those record warm Atlantic SSTs and the faster Pacific Jet allowed the ridge over our area to verify stronger than forecast today.

Verification already 50° at Newark

 

Old forecast was colder for today

 

 

Record warm Atlantic SSTs

https://mco.umaine.edu/gom_sst/

 

 

 

Evidence continuing to mount for a well above normal stretch coming up, the SPV problem also there: 

 

 

[HeadInTheClouds]

It's like night and day from where I live in the MHV to NYC metro and it's only about 75-80 miles to Manhattan. No leaves, already had a little snow last weekend, and it's gone down to 20* a few nights. Has Central Park hit freezing yet? 

[EasternLI]

Thinking that this west pacific Typhoon is messing with that west pacific mjo. For now anyway.

[donsutherland1]

Overnight, it will be mostly cloudy with some showers. Tomorrow will be unseasonably mild with temperatures rising well into the 50s in much of the region. Colder air will return on Friday. No Arctic blasts appear likely for the foreseeable future even as meteorological winter has now gotten underway.

First measurable snowfall statistics for select cities:

Allentown: Normal: December 6; 2020-21: December 9
Bridgeport: Normal: December 3; 2020-21: December 16
Islip: Normal: December 10; 2020-21: December 16
New York City: Normal: December 13; 2020-21: December 16
Newark: Normal: December 9; 2020-21: December 9; 2021-22: November 28
Philadelphia: Normal: December 19; 2020-21: December 16

Out West, Denver has yet to see its first measurable snowfall through November 30. The previous record latest first measurable snowfall occurred on November 21, 1934.

Incredible warmth prevailed in parts of the West today. Preliminary record values included:

Bismarck: 66° (old record: 62°, 1969) ***tied December record***
Denver: 73° (tied daily record set in 1973)
Glasgow, MT: 66° (old record: 62°, 1925)
Great Falls: 69° (old record: 60°, 1907 and 1969) ***tied December record***
Helena: 69° (old record: 60°, 2008) ***new December record***
Kalispell, MT: 61° (old record: 54°, 1925) ***new December record***
Missoula, MT: 66° (old record: 55°, 1972) ***new December record***
Omak, WA: 72° (old record: 57°, 1949) ***new December record***
Phoenix: 85° (old record: 83°, 1949)
Rapid City: 72° (old record: 71°, 1973)
Sheridan, WY: 76° (old record: 71°, 1995)
Tucson: 85° (old record: 84°, 1926) ***tied December record***

Atlantic blocking (AO and NAO) is continuing to break down. As a result, temperatures will likely turn milder for at least a time. Although the first 10 days of December could average somewhat cooler than normal overall from a lag in the pattern response to the breakdown in Atlantic blocking, the first half of the month overall will likely average near normal or somewhat warmer than normal. Afterward, developments related to the EPO and AO could determine the outcome for much of the remainder of the month. For now, there remains uncertainty about the evolution of the teleconnections. However, it appears more likely than not (60% implied probability) that December will see a warm anomaly in the Northeast.

Following very wet July-September periods, winter (December-February) precipitation has typically been near or below normal. The most recent exception was winter 2018-19.

The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was -0.7°C for the week centered around November 24. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.80°C and the ENSO Region 3.4 anomaly has averaged -0.90°C. La Niña conditions will likely persist into at least late winter.

The SOI was +10.74 today.

The preliminary Arctic Oscillation (AO) figure was +1.646 today.

On November 29 the MJO was in Phase 5 at an amplitude of 1.155 (RMM). The November 28-adjusted amplitude was 1.018 (RMM).

[lee59]

Correct me if I am wrong but todays highs are 49 in Central Park, 50 at Teterboro and 56 at Newark. If that is correct, maybe Newark is having instrument problems. I had a high of 50 degrees.

[wdrag]

Added CPC's monthly outlook for Dec: available for end of month comparison just to show how difficult it is to outlook beyond 2 weeks.  

 

I don't recall CPC's October outlook for our area???? Maybe someone has the graphic. Was it below normal Nov temps and below normal qpf?

[Stormlover74]

18 minutes ago, lee59 said:

Correct me if I am wrong but todays highs are 49 in Central Park, 50 at Teterboro and 56 at Newark. If that is correct, maybe Newark is having instrument problems. I had a high of 50 degrees.

Actually 58 was their high. 8 degrees higher than any other site in a 30 mile radius. Definitely bogus

Tomorrow should be 65

[RippleEffect]

any snow showing on models? i want snow man this weather is boring i want snow now. currently 45 degrees expecting some showers in a few hours!

[LoboLeader1]

48* was the high here today, current temp now is 40*

[bluewave]

2 hours ago, EasternLI said:

Thinking that this west pacific Typhoon is messing with that west pacific mjo. For now anyway.

 

I think that this wave break may be having a bigger influence. It eventually pumps the Aleutians Ridge. Then the -PNA trough digs into the Pacific Northwest boosting the Southeast Ridge during the 2nd week of December.