December 2025 OBS and Discussion

[MJO812]

2 minutes ago, David-LI said:

have a snow map?

Several inches

This is getting interesting 

[NEG NAO]

The problem with the Euro is that HP in Canada is not holding in place compared to the GFS - the LP is allowed to move further north

[MJO812]

2 minutes ago, NEG NAO said:

The problem with the Euro is that HP in Canada is not holding in place compared to the GFS - the LP is allowed to move further north

Its further south like the other models. Good trends tonight. 

[NEG NAO]

Just now, MJO812 said:

Its further south like the other models. Good trends tonight. 

agreed and its only 5 days away....

[MJO812]

5 minutes ago, NEG NAO said:

agreed and its only 5 days away....

Yep. Now the eps is also south. 

Looks like the models latched on to the blocking tonight. 

[NEG NAO]

3 minutes ago, MJO812 said:

Yep. Now the eps is also south. 

Looks like the models latched on to the blocking tonight. 

yes and since its multiple models  trending that way and its only 5 days away chances are good we will have at least some sort of frozen event - still way too early for details..........

[MJO812]

Icon well south now

[The 4 Seasons]

5 minutes ago, MJO812 said:

Icon well south now

But what does the Navy say? Oh wait, it hasn't run since Thanksgiving. Guess it's hibernating for now.

Good runs overall tonight, AI models as well. Big moves, good moves. 

MJO- No Access to MA? What happened, they banned you in the Mid Atlantic forums?

[MJO812]

1 hour ago, The 4 Seasons said:

But what does the Navy say? Oh wait, it hasn't run since Thanksgiving. Guess it's hibernating for now.

Good runs overall tonight, AI models as well. Big moves, good moves. 

MJO- No Access to MA? What happened, they banned you in the Mid Atlantic forums?

Yes just for posting maps. Its stupid. 

Anyway gfs is even further south

Gfs and AI gfs

[MJO812]

Gefs further south 

[MJO812]

AI Euro slightly more south

[MJO812]

6z euro continues the theme. Slightly more colder.

6z eps slightly colder and south of 0z eps

[brooklynwx99]

pretty legit trend in the confluence for late week. Fri-Sat is def a timeframe to watch for a legit thump

[bluewave]

All we can say for sure is that the -NAO corrected much stronger and the PNA more negative with a stronger trough digging into the West. Certainly an unusual looking setup for snow here. But the kicker low over the Dakotas prevents the low near our area from riding too far north. So in an odd way the stronger -PNA actually helps which we don’t see much. The solution will probably change in the coming days with all the moving parts. 
 

New run

Old run

 

 

[wthrmn654]

Weather channel just talked about that.  Icy and snowy potential!

[SHELEG]

GFS is so far south it’s a miss.

[SACRUS]

 

27 / 14 sunny.  Progressing to an overall near / below normal once passed the warmup Christmas (Eve/Day) 12/24 - 12/26.  Friday into Sat slop / flop or snow to rain.  Warmth to the south / west and cold pushing down into the northeast.  Next storm threat, beyond Friday/Sat is for the 30/31.  Beyond there - near normal.

 

[SACRUS]

Records:

Highs:

EWR:  71 (2013)
NYC: 71 (2013)
LGA: 69 (2013)
JFK: 64 (2013)


Lows:

EWR: 7 (1989)
NYC: 4 (1872)
LGA: 8 (1989)
JFK: 9 (1989)

Historical:


1779: One of the "Hardest Winters" The winter of 1779-1780: This winter was so cold that ice was said to have been piled 20 feet high along the Virginia Coast and stayed there until spring. The upper portion of the Chesapeake Bay was frozen, allowing people to walk from Annapolis to Kent Island, Md. The Virginia portion of the Bay was frozen near the mouth, as well as all waterways in Virginia, which were firm enough to support the crossing of a regiment of the Virginia Infantry fighting the War of Independence as it marched from Falmouth to Fredericksburg, crossing the Rappahannock River, which had been frozen since the previous November. (Ref. Virginia Weather History)

1783: One of the "Long Winters" The winter of 1783-1784: Not as cold as 1780, this winter lasted longer into the spring, and was thought to rank near the top for extremes in cold and snow. The Chesapeake Bay once again froze almost all the way to the mouth. James Madison in Orange County, Va. wrote in a letter to Thomas Jefferson, " We had a severer season and particularly a greater quantity of snow than is remembered to have distinguished any preceding winter." The thaw caused an ice jam on the James River at Richmond that gave way, causing a flash flood of ice and water that swept away a bridge and sank boats that were tied up below the falls. Ice on the Potomac did not break until March 15th. (Ref. Virginia Weather History)
 

1839 - The second of triple December storms hit the northeastern U.S. The storm produced 25 inches of snow at Gettysburg, PA, and gales in New England, but only produced light snow along the coast. (David Ludlum)
Dec. 22-23, 1839: Snow began around 3 a.m. in Washington, DC as a northeast gale intensified. The storm reached its greatest intensity around 9 p.m. that evening when the barometer dropped to its lowest point, 29.25 inches. Then the wind backed toward the northwest and snow continued until morning, with 10 inches accumulation in the city.(Ref. Virginia Weather History)

1908: The most snow to fall to date in Richmond since weather records were started in 1897 was 15.0 inches that fell just before Christmas in 1908. (Ref. Richmond weather recorded - KRIC)

 

1961 - Holiday travel was paralyzed over extreme northeastern Kansas, and adjacent parts of Missouri, Iowa and Nebraska. The storm produced 5 to 15 inches of snow, with drifts up to ten feet high. (22nd-23rd) (The Weather Channel)

1975: On December 20th through December 22nd 18.5 inches of snow fell over the Boston, Massachusetts area. This was their heaviest December snowstorm. Also on the 22nd Boston, Massachusetts had 14.0 inches of snow on the ground, greatest ever for December. (Ref. NOAA Boston Weather Events)

1983: On the first day of winter 75 cities reported record low temperatures for the date, with twelve of those cities reporting record low temperatures for the month as a whole. The mercury plunged to 51 degrees below zero at Wisdom MT, and Waco, TX set all-time records low a reading of 12 above zero.(The National Weather Summary)
Wind chill readings were as low as -100 °F over a large part of North Dakota. Many locations from the West Coast to the Ohio Valley reported record low temperatures for the date including: West Yellowstone, MT: -43 °F, Williston, ND: -38 °F, Valentine, NE: -37 °F, Virginia City, MT: -35 °F, North Platte, NE: -34 °F, Casper, WY: -33 °F, Lander, WY: -31 °F, Bismarck, ND: -30 °F.(Ref. Wilson - Additional Temperatures Listed On This Link)

1983 - On the first day of winter 75 cities reported record low temperatures for the date, with twelve of those cities reporting record low temperatures for the month as a whole. The mercury plunged to 51 degrees below zero at Wisdom MT, and Waco TX set an all-time record low a reading of 12 above zero. (The National Weather Summary)

1987 - The first day of winter was a relatively tranquil one for much of the nation, but heralded a winter storm in the Central Rockies. The storm produced 40 inches of snow at the top of the Pomerelle Ski Resort, south of Burley ID, the heaviest snow of record for that location. (The National Weather Summary) (Storm Data)

1988 - Strong winds prevailed in the foothills of Wyoming and Colorado. Winds gusted to 123 mph southwest of Fort Collins CO, and reached 141 mph at the summit of Mount Evans. An ice storm paralyzed parts of Upper Michigan during the day. The freezing rain left roads around Marquette MI blocked by cars and semi- trucks. (The National Weather Summary) (Storm Data)

1989 - A total of 137 cities across the central and eastern U.S. reported record low temperatures for the date. Thirty-five of those cities established record lows for the month of December. Morning lows of 23 degrees below zero at Kansas City MO, 26 degrees below zero at Concordia KS, and 27 degrees below zero at Goodland KS established all-time records for those three locations. Unofficial morning lows included 50 degrees below zero at Recluse WY and 60 degrees below zero at Rochford SD. Broadus MT and Hardin MT tied for honors as the official cold spot in the nation with morning lows of 47 degrees below zero. Chinook winds at Cutbank MT helped warm the temperature 74 degrees, from a morning low of 34 degrees below zero to an afternoon high of 40 degrees. (The National Weather Summary) (Storm Data)

 

1989: The most significant cold spell of the century for the Deep South occurred from the 22 to the 26. New Orleans experienced 64 consecutive hours at or below 32 degrees Fahrenheit and a total of 81 out of 82 hours below freezing. A total of 15 hours was below 15 degrees with the lowest reading of 11 degrees on the morning of the 23rd. A low temperature of 8 degrees was recorded at Baton Rouge. Snow and sleet paralyzed transportation systems where as much as two to four inches of snow accumulated in Lafourche and Terrebonne Parishes. Snow and ice-covered the ground in New Orleans. The most significant impact was the breaking of water pipes in homes and businesses. Over 100 fires resulted in the New Orleans area within 24 hours due to a loss of water pressure and improperly utilized heating sources. Ice formed over shallow lakes and waterways where commercial fishing took heavy losses. Five weather-related deaths occurred in the service area during this rare Arctic outbreak.  Between December 22 and December 24, 1989, deepening low pressure pulled a frigid arctic air mass into the southeastern United States. This sequence of events produced a historic snowstorm and a rare white Christmas across the region. At Charleston, South Carolina, the storm deposited 8 inches of snow – the greatest snowfall in modern history. At Savannah, Georgia, the storm total accumulation of 3.6 inches tied the greatest snowfall in modern history.

1990: ALL-TIME RECORD LOWS in Casper, WY -41 °F, Redding, CA +17 °F, Worland, WY -50 °F, Sacramento, CA +21 °F, and wind chills in ND. of -70 °F to -80 °F BELOW ZERO.(Storm Data)
Wind chills in parts of North Dakota dropped as low as -80 °F. Locations reporting all-time record lows included: Worland, WY: -50 °F, Spring Valley State Park in Lincoln County, Nevada: -38 °F, Winnemucca, NV: -37 °F (broke previous daily record by 25 degrees), Denver, CO: -25 °F-Tied. Cheyenne, WY and Dodge City, KS equaled December record lows with -28 °F and -21 °F respectively. Locations reporting daily record lows included: Wisdom, MT: -52 °F, Lincoln Ranger Station, MT: -48 °F, Butte, MT: -44 °F, Chester, MT: -44 °F, Boulder, MT: -42 °F, Conrad, MT: -40 °F.(Ref. Wilson - Additional Temperatures Listed On This Link)

1993: Five inches of snow fell in just 20 minutes at Turin, NY. The town would be buried under 45 inches of snow during the lake effect snow event. Boonville, NY recorded 31 inches over a two day period. (Ref. Wilson Wx. History)

2001: Reagan National Airport in Washington, DC dropped to 29 degrees for a morning low for their first freezing temperature of the season. This set a new record for its latest first freezing temperature breaking the previous record of 12/14/1980. This also was the first time the location had not recorded a freezing temperature during the autumn season.(Ref. Wilson Wx. History) (Ref. Weather Guide Calendar with Phenomenal Weather Events 2011 Accord Pub. 2010, USA)

 

2004: Tremendous snows occurred in the Ohio Valley. The following cities set new records for their most significant snowstorm ever: Evansville, Indiana 22.3 inches, Dayton, Ohio 16.4 inches, and Paducah, Kentucky 14.2 inches. Other big snowfall totals were 31 inches at Liberty, Indiana, 28 inches at Buena Vista, Indiana, 24 inches at Greenville, Ohio, and 23 inches at Mansfield, Ohio. 

2005: Southern Illinois: A fast moving snowstorm across the Midwest and Ohio Valley becomes the most significant snowstorm on record for southern sections of Illinois. Snowfall records are set at Carbondale (12 inches), McLeansboro (14 inches), and Carmi (18 inches).(Ref. WxDoctor)

2008: Wisconsin: Most of Wisconsin shivers as temperatures fell to below zero (-18 °C) with even colder wind-chill temperatures. The only parts of the state with above zero readings are in cities along Lake Michigan. The low temperatures hit -13 °F in Hayward and -12 °F in La Crosse. (Ref. WxDoctor)

[SACRUS]

 

Dec Dep through the first 2/3 of the month (12/21)
 

LGA: -6.7
NYC: -6.3
EWR: -5.9
JFK: -5.8
ISP: -3.4

[SACRUS]

Pause the Mamma and Papa's - California Dreamin for about a week

 

[bluewave]

18 hours ago, North and West said:

Honest question, why does everyone lose their minds with long range models (no matter that they show), when they’re just going to change anyway? It’s a seasonal tradition.


.

People don’t mind as much if the models underpromise and the storm overperforms like January 2016.

But it’s a whole different ballgame when the models overpromise and the storm underperforms like January 2015.

Don’t even get started talking about the model initialization errors discussion a few days before the Boxing Day Blizzard. 

[NEG NAO]

28 minutes ago, bluewave said:

People don’t mind as much if the models underpromise and the storm overperforms like January 2016.

But it’s a whole different ballgame when the models overpromise and the storm underperforms like January 2015.

Don’t even get started talking about the model initialization errors discussion a few days before the Boxing Day Blizzard. 

You can read all about it here starting with this thread from 15 years ago

 

[wthrmn654]

54 minutes ago, SACRUS said:

 

Dec Dep through the first 2/3 of the month (12/21)
 

LGA: -6.7
NYC: -6.3
EWR: -5.9
JFK: -5.8
ISP: -3.4

Thankfully still below normal, by a fake amount i might add even after record highs! 

[SnowGoose69]

1 hour ago, SHELEG said:

GFS is so far south it’s a miss.

Yeah that definitely won't happen.  I'd still lean towards this probably being too far north for anything here, but there is potential now for something when 2-3 days ago there was none.

[bluewave]

5 minutes ago, NEG NAO said:

You can read all about it here starting with this thread from 15 years ago

 

One of my favorite blizzards back in Long Beach with some of the best drifting.

 

[wthrmn654]

Oh, if no one knew there were some weather models added/ upgraded December 17th.

AIGFS, AIGEFS and HGEFS Implementation
Implementation of the initial versions (v1.0) of the AIGFS, AIGEFS and HGEFS

 

https://www.weather.gov/media/notification/pdf_2025/scn25-89_AIGFS_AIGEFS_and_HGEFS.pdf

[bluewave]

9 minutes ago, wthrmn654 said:

Oh, if no one knew there were some weather models added/ upgraded December 17th.

AIGFS, AIGEFS and HGEFS Implementation
Implementation of the initial versions (v1.0) of the AIGFS, AIGEFS and HGEFS

 

https://www.weather.gov/media/notification/pdf_2025/scn25-89_AIGFS_AIGEFS_and_HGEFS.pdf

It will be interesting to see how well the Qubitcast does.

https://www.artemis.bm/news/planette-develops-qubitcast-to-detect-severe-weather-events-up-to-six-months-in-advance/

 

[SnowGoose69]

The EPO/PNA still suck in the long range, so it won't be going January 94/85 February 2015 anytime soon but the location of the PV being on this side of the pole will mean it can easily get cold enough for snow and the -PNA means we are not in a bone dry pattern.  The AO/NAO have the look of not wanting to consistently stay strongly - or + so far for more than 7-10 days and often times if thats your trend through 12/31 it stays that way all winter so those 2 may largely be non major factors.   The PNA/WPO/EPO at some stage likely go through a major reversal of where they've been in the next 20-30 days and that probably decides what the 1/15-3/10 period is

[RU848789]

Nice NWS-Philly discussion of the possible 12/26 event.  Would love to score a "surprise" snowfall on Friday.  

Area Forecast Discussion
National Weather Service Mount Holly NJ
546 AM EST Mon Dec 22 2025

Beyond Christmas Day, forecast uncertainty becomes very high.
Guidance indicates there will be a high over eastern or
southeastern Canada with low pressure moving eastward across the
Great Lakes and toward the Northeast or Mid Atlantic. This
setup will likely bring precipitation to our area. The 00Z suite
of guidance had a significant change in course, indicating a
much stronger high and weaker, more suppressed low. This
solution would introduce potential for wintry precip for our
region and much colder temperatures, quite the change from
widespread 50s and rain from before. The shift in guidance was
consistent between different models. GFS, ECMWF, and CMC all
showing this much colder, wintry solution now, however given
this *very* recent change in course, have stuck with NBM for now
until there is more consistency in a colder, more wintry
solution. Precipitation is still likely, with 50-80% PoPs,
however we could be dealing with all rain, a significant wintry
system, or anything in between. Remain alert for changes to the
forecast for the Friday timeframe.

[MJO812]

Icon slightly more south