December 2025 OBS and Discussion

[Volcanic Winter]

1 hour ago, snowman19 said:

I wasn’t born yet lol but looking back on the weather history, the 1989-90 winter was probably (easily) the most extreme pattern flip we’ve seen in the last 50 years. We went from a record cold arctic tundra starting in November right through the end of December, then got a big cutter on New Year’s Eve and that was all she wrote, light switch flip to an unmitigated torch for all of January and February….

That’s really incredible. Weather and climatology are so fascinating to me, so many variables at any given time producing innumerable outcomes - sometimes resulting in extreme permutations.

I was born in the late 80’s so of course wasn’t around for the extremes of that decade. One of my first vivid weather memories however was the blizzard of 96… not a bad one to have. Was in Monmouth county for that as a kid. 

[snowman19]

21 minutes ago, jm1220 said:

If we have a slightly negative or neutral PNA that would drive a more zonal jet stream, it could work with a -NAO, but a sharply negative -PNA would drive such a deep trough on the west coast that the SE ridge would respond and possibly link with the NAO block. That’s obviously what we want to avoid. 

I believe @bluewave discussed the possibility of that happening (SE ridge hooking up with the -NAO) last week. A -PNA would definitely make that possibility more likely as you said

[EastonSN+]

10 minutes ago, snowman19 said:

I believe @bluewave discussed the possibility of that happening (SE ridge hooking up with the -NAO) last week. A -PNA would definitely make that possibility more likely as you said

Especially if the RNA is closer to the west coast and -2 or less.

Would not happen in a +PNA.

[Krs4Lfe]

28 minutes ago, EastonSN+ said:

Especially if the RNA is closer to the west coast and -2 or less.

Would not happen in a +PNA.

Yeah that's the benchmark to watch. If we see a deeply negative PNA, then rest of winter would probably be similar to winter 2023 and 2024. Big time snow and cold in the west, and warm and mild over here

[NEG NAO]

[North and West]

It was wild to say the least.    Most of the snow was suppressed south however.   Savannah, GA had a 10 inch snowstorm right before Xmas.   Around the 30th-it broke and never came back-Jan/Feb/Mar were absolute infernos

I remember being at my grandparents’ on New Year’s Eve and snow changing to rain. I then remember going to church in January in shorts, and then it snowed in early April.

Best part is that I got to do the weather report for my class the first week of December.

Wild second grade for sure.


.

[psv88]

36 today

[psv88]

Solar panels producing some power again today. Melt away

[qg_omega]

Weeklies are wall to wall warmth for January

[vegan_edible]

10 minutes ago, qg_omega said:

Weeklies are wall to wall warmth for January

everyone gets on snowman for being the debbie downer... but he has facts and stats to back his words up. 

 

i don't think i've seen you post one credible piece of info yet, and your call before thanksgiving led to one of the coldest starts to december we've seen in recent years. 

reverse psychology? old man yelling at cloud? just general dreadful demeanor so you can be a contrarian to what others on this board are hoping to see? 

whatever it is, it worked last time. so maybe this time, it will again:)

 

also. i've seen the weeklies. nothing is set in stone here...

[JenkinsJinkies]

5 minutes ago, vegan_edible said:

also. i've seen the weeklies. nothing is set in stone here...

It is also more than 2 weeks until the start of January.

[donsutherland1]

Temperatures will moderate for tomorrow through Friday. Thursday and Friday will be mild days with the mercury approaching or reaching 50° in parts of the region. A soaling rain is likely Thursday night and Friday. Much of the region could see a general 0.50"-1.50" of rain.

Behind the storm, the weekend will turn somewhat cooler. 

The probability that December 2025 will have a maximum monthly temperature below 60° is increasing. The last time that happened was in 2019 when the monthly high was 58°. If 2025 has a monthly high below 60°, that would be only the fifth such occurrence since 2000 (2003, 2004, 2005, and 2019 are the cases since 2000).

The ENSO Region 1+2 anomaly was -0.3°C and the Region 3.4 anomaly was -0.7°C for the week centered around December 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.33°C and the ENSO Region 3.4 anomaly has averaged -0.67°C. La Niña conditions will likely continue through at least mid-winter.

The SOI was -0.88 today. 

The preliminary Arctic Oscillation (AO) was +1.524 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied near 97% probability that New York City will have a cooler than normal December (1991-2020 normal). December will likely finish with a mean temperature near 34.3° (4.8° below normal). 

Supplemental Information: The projected mean would be 3.1° below the 1981-2010 normal monthly value. 

 

[Roger Smith]

Until you see a temp above 47 F, Dec 2025 remains tied with 1917 in first place for lowest max. Sadly that probably won't survive. 

Today's departure looks like it could push the running anomaly down to around -9 F which will perhaps be the low point for the month. As I was saying yesterday, lots of ups and downs ahead and I would expect this anomaly to be cut in half but -5 to -6 for the month is still possible if there's enough cold in the mix.  

If the mean after today drops to 32.4 F it will currently be tied with three t-28th coldest Decembers (for the entire month), a finish closer to 36 F seems likely, and the median of all 157 (if below 36.5) will be 36.5 F so there is some chance of the month being in the lower half of all Decembers, something that only happens two or three times a year in the modern and urban-warmed climate. 

A total of 26 Decembers had a mean at or below 32.0, the only recent ones being 1989 and 2000. By decades it is fairly easy to see the warming of the climate but about half of this is likely due to urban heat island increases. (27th was 1892 at 32.2 and the three at t-28th 32.4 are 1909, 1944 and 1995). Three more (1902, 1921, 1980) were tied at 32.5 F.

 

• DECEMBERS WITH MEANS 32.0 OR LOWER (listed by 30-year intervals slightly modified,

1869-1900 (8), 1901-30 (7), 1931-60 (6), 1961-90 (4), 1991-2024 (1).

1871 (29.2), 1872 (28.3), 1876 (24.9), 1880 (26.5), 1882 (30.6), 1883 (32.0), 1886 (29.6), 1890 (29.9)

1903 (31.5), 1904 (30.3), 1910 (30.0), 1914 (31.6), 1917 (25.0), 1919 (30.2), 1926 (28.9)

1935 (30.0), 1942 (31.1), 1945 (31.0), 1955 (29.7), 1958 (29.4), 1960 (30.9)

1962 (31.5), 1963 (31.2), 1976 (29.9), 1989 (25.9)

2000 (31.1)

 

[jetrz]

Today was the 20th consecutive day of below normal temperatures at Central Park. Anyone know where to find out how long its been since we've had such a streak?

[the_other_guy]

6 hours ago, Krs4Lfe said:

Yeah that's the benchmark to watch. If we see a deeply negative PNA, then rest of winter would probably be similar to winter 2023 and 2024. Big time snow and cold in the west, and warm and mild over here

That would be a mega flip. Out west is dying this year with low snow and AN.

 

Have we ever seen a winter with such a large flip like that for the whole country? It would be extraordinary

[Brian5671]

4 hours ago, vegan_edible said:

everyone gets on snowman for being the debbie downer... but he has facts and stats to back his words up. 

 

i don't think i've seen you post one credible piece of info yet, and your call before thanksgiving led to one of the coldest starts to december we've seen in recent years. 

reverse psychology? old man yelling at cloud? just general dreadful demeanor so you can be a contrarian to what others on this board are hoping to see? 

whatever it is, it worked last time. so maybe this time, it will again:)

 

also. i've seen the weeklies. nothing is set in stone here...

the weeklies can be awful-a couple years ago they showed cold all winter and we baked

[JerseyWx]

People on here never cease to amaze.  Month to date I'm running about -7 on the lows and -9 on the highs.

Does it need to snow every 3 days or something?  It's been plenty cold and there's snow on the ground.  That's what you get in the metro in December, we're not in the northern Rockies.

[psv88]

14 minutes ago, JerseyWx said:

People on here never cease to amaze.  Month to date I'm running about -7 on the lows and -9 on the highs.

Does it need to snow every 3 days or something?  It's been plenty cold and there's snow on the ground.  That's what you get in the metro in December, we're not in the northern Rockies.

Who is upset? People are talking about the pattern to come, not the past month. 

[JerseyWx]

39 minutes ago, psv88 said:

Who is upset? People are talking about the pattern to come, not the past month. 

If you scroll the last few pages there is the typical doom and gloom that we just got lucky with the last event and more cutters to come!

People love winter so much, then enjoy what you have instead of what's on a model run 10 days away.

[bncho]

GFS says Merry Christmas for y'all lol

[NEG NAO]

Next Week we will have blocking with strong HP in southeast Canada - the position of the HP and strength will determine how far south and west this cold enough air will spread and any disturbance that runs into it could cause frozen precip in the cold enough regions - this has been showing up on various models for days now

[SnowGoose69]

Thats like a -7 NAO on the GFS at 300.  I'm sure the GEFS will look different.

[SnoSki14]

17 hours ago, snowman19 said:

I wasn’t born yet lol but looking back on the weather history, the 1989-90 winter was probably (easily) the most extreme pattern flip we’ve seen in the last 50 years. We went from a record cold arctic tundra starting in November right through the end of December, then got a big cutter on New Year’s Eve and that was all she wrote, light switch flip to an unmitigated torch for all of January and February….

We need to stop comparing today to 35+ year old analogs. The climate has changed drastically. There are way too many variables in play today vs then. 

[MJO812]

5 hours ago, NEG NAO said:

Next Week we will have blocking with strong HP in southeast Canada - the position of the HP and strength will determine how far south and west this cold enough air will spread and any disturbance that runs into it could cause frozen precip in the cold enough regions - this has been showing up on various models for days now

Yep have to watch this timeframe.  The NAO is goijg negative. 

[EasternLI]

Can we please make this a thing. Thanks. 

[bluewave]

All we can say is that the first 16 days of December have been one of our coldest 16 day periods relative to the means of the 2020s so far. The clipper was a nice contribution to this period feeling very wintry around the area.

This was actually the coldest first half of December  in 20 years. The new Newark records for December now go back to 1850.  So this was ranked 26th coldest which is very respectable in our warmer 2020s climate. 

The current 7 station departure across the area is -7.7. With the moderation coming up next few weeks, the final number this month may finish in the  -3 to -4 range. Models have been fluctuating from run to so we won’t know the exact number for a weeks.
 

EWR…..-8.1

NYC……-8.7

LGA……-8.7

JFK…….-7.8

HPN……-7.6

BDR…...-7.9

ISP……..-5.4

AVG…….-7.7

 

Time Series Summary for NEWARK LIBERTY INTL AP, NJ Coldest  12-01 to 12-16 periods 
Click column heading to sort ascending, click again to sort descending.

1	1867-12-16	24.1	5
2	1904-12-16	24.6	0
3	1910-12-16	25.5	0
4	1917-12-16	25.7	4
5	1876-12-16	27.0	5
6	1868-12-16	27.3	3
7	1958-12-16	27.9	0
-	1871-12-16	27.9	1
8	1902-12-16	28.6	0
9	1989-12-16	28.8	0
-	1869-12-16	28.8	4
10	1860-12-16	28.9	2
11	1880-12-16	29.0	3
12	1895-12-16	29.1	2
13	1859-12-16	29.4	4
14	1886-12-16	29.5	4
15	1882-12-16	29.7	2
16	1915-12-16	29.8	1
17	1903-12-16	30.0	0
-	1872-12-16	30.0	2
18	2005-12-16	30.4	0
19	1976-12-16	30.6	0
20	1854-12-16	30.8	3
21	1898-12-16	31.0	0
22	1937-12-16	31.1	0
23	1942-12-16	31.2	0
24	1875-12-16	31.4	0
25	1851-12-16	31.7	4
26	2025-12-16	31.8	0
-	1945-12-16	31.8	0

[SACRUS]

29 / 21 warm the next 3 days Wed - Fri with perhaps some of the warmest areas touching or close to 60 on Friday, otherwise mid/upper 50s.  Overnight Thu into Fri upto an inch of rain.   Colder Saturday - warmer Sunday- then back down Mon - tue before warming Chirstmas eve.  Overall looking warmer between Christmas and the 30th with strong nationwide ridge perhaps a day in there that approach 60 / record high?.  Colder air just to the north and the warmest is to the south west.   Still would watch the period 12/30-31. 

 

[SACRUS]

 

Records:
 

Highs:

EWR: 66 (2000)
NYC: 62 (2000)
LGA: 62 (2021)
JFK: 61 (2021)


Lows:

EWR: 6 (1951)
NYC: 1 (1919)
LGA: 9 (1951)
JFK: 16 (1973)

Historical:

1796: The drought is excessive. From the middle of October to the middle of December, not rain enough to lay the dust. A few days ago there fell a small rain, but the succeeding cold has probably prevented it from sprouting the grain sown during the drought. (Monticello - Thomas Jefferson to James Madison- Jefferson's Garden Book by Edwin Morris Betts page 252)
 

 

1884 - A three week blockade of snow began at Portland, OR. A record December total of 34 inches was received. (David Ludlum)

 

1903: Wilbur and Orville Wright made four brief flights at Kitty Hawk, North Carolina with their first powered aircraft on this day. After having success with their 5-foot biplane kite, the brothers realized the weather conditions in Dayton were not ideal for their flying experiments. They wrote the Weather Bureau in Washington, D.C. requesting a list of suitable places on the east coast where winds were constant. Below is the response the Wright Brothers received from Joseph Dosher, who staffed the Weather Bureau office, wrote in August of 1900 regarding the suitability of Kitty Hawk.

1924 - A severe icestorm struck central Illinois. It coated the ground with nearly two inches of glaze at Springfield. The storm caused 21 million dollars damage along with much hardship. Ice was on the trees until the 4th of January, and electricity was not restored until January 10th. (David Ludlum)

 

1924:  From the Monthly Weather Review, "a severe glaze storm occurred in west-central Illinois on December 17 and 18, the area of great destruction embracing a territory about 75 miles in width and 170 miles in length. In the affected area, trees were badly damaged, wires broken, and thousands of electric poles went down. Electric services were paralyzed, and it required weeks to restore operation and months to permanently rebuild the lines.  The street railway company and the Illinois Traction System resumed complete operation 17 days after the storm. Electric light service was completely restored January 10. The ice had practically disappeared from the trees and wires by January 4, but on January 20, there was still considerable ice on the ground.  The Western Union Telegraph Co. lost 8,000 poles and the Illinois Bell Telephone Co. about 23,000. The total damage to wire service in Illinois probably equaled or exceeded $5,000,000." If the loss of business, the damage to trees and possible injury to winter grains, the storm may be considered one of the most disastrous of its kind in the history of Illinois."

1929 - An icestorm in western New York State resulted in much damage and hardship. A Buffalo report stated, "one was kept awake by the breaking limbs, which snapped off with a report much louder than a rifle shot." (17th-18th) (The Weather Channel)

1930: Greensboro, NC experienced its greatest 24-hour snowfall when 14.3 inches fell. (Ref. AccWeather Weather History)

1932: The 10TH GREATEST Washington, DC snow. The snow began early on the 17th and fell at a rate of 1 to 2 inches per hour until afternoon with a 12 inch accumulation. It was a rather cold storm with temperatures hovering around 18 degrees F during the height of the snow. Temperatures rapidly warmed after the storm and the snow was gone by Christmas. (p. 58-59 Washington Weather Book 2002 by Ambrose, Henry, Weiss)


1973: 10.2 inches of snow in Washington, DC on 16th and 17th (Washington Weather Records KDCA)

1963: Lake effect snow buried Muskegon, MI with a three day total of 34 inches of snow from the 16th to the 18th. This will be the snowiest December in Muskegon history with a grand total of 82.6 inches. (Ref. Wilson Wx. History)

1964: 20 inches of snow fell at Walla Walla, WA set a state record for December. (Ref. AccWeather Weather History)

1967: A four-day snow and ice storm, described as the worst major ice storm in Oklahoma in more than a decade, ended during the morning hours. The storm affected all but the southeast part of the state, with ice accumulations of a half to 1 inch. Local ice accumulations of 4 inches were reported at Cordell. More than 225 people were treated for injuries, after slipping on the ice. At least 170 of these injuries were in the Oklahoma City area. (Ref. Wilson Wx. History)

1973: A snowstorm along the Mid-Atlantic gave Washington, DC 10.2 inches of pre-Christmas snow. (Ref. Wilson Wx. History)

1983: Billings, MT had a high temperature was -8 °F; this was the first of 8 consecutive days with a high temp below zero, a December record. One of the most severe Arctic outbreaks to affect the Great Plains gripped Oklahoma for more than two weeks in late December. The prolonged cold wave, lasting from the 17th through the 31st, lowered Oklahoma City's average temperature for the month to a cold 25.8 °F, their coldest on record. Locations that reported record low temperatures for the date included: International Falls, MT: -35 °F, Great Falls, MN: -27 °F: Tied, St. Cloud, MN: -24 °F, Valentine, NE: -23 °F, Duluth, MN: -21 °F: Tied, La Crosse, WI: -18 °F, Minneapolis, MN: -17 °F, Marquette, MI: -9 °F, Omaha, NE: -9 °F: Tied and Clayton, NM: 2 °F.(Ref. Wilson Wx. History)

1987 - A storm in the southwestern U.S. brought heavy rain and heavy snow to parts of California, Nevada, Arizona, Utah and New Mexico. Charleston NV was blanketed with 12 inches of snow. Lake Havasu City AZ was drenched with 2.26 inches of rain. (Storm Data) (The National Weather Summary)

1988 - Squalls brought locally heavy snow to the southeastern shores of Lake Michigan. Totals in Michigan ranged up to 14 inches at Harvey. Totals in Ohio ranged up to 16 inches at Chardon. (The National Weather Summary) (Storm Data)

1989 - Twenty-one cities from Kentucky to Pennsylvania reported record low temperatures for the date, including Columbus OH with a reading of 12 degrees below zero. Heavy snow continued in the Colorado Rockies. Vail received 65 inches of snow between the 14th and the 18th of December. Steamboat Springs was buried under 74 inches, and reported a total of 108 inches of snow between the 10th and the 18th of the month. (The National Weather Summary) (Storm Data)

2002 - Thunderstorms preceding a strong cold front pushed into the U.S. Mississippi Valley, producing severe weather and tornadoes. Three people were killed in Missouri and Arkansas with more than 40 injuries (Associated Press).

2008 - A winter storm dumped as much as 3.6 inches of snow across Las Vegas, Nevada, prompting the closure of schools and highways. This was the largest December snowfall on record and the heaviest snowfall since January 1979 when a total of 7.5 inches fell (Associated Press).

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41 minutes ago, SACRUS said:

29 / 21 warm the next 3 days Wed - Fri with perhaps some of the warmest areas touching or close to 60 on Friday, otherwise mid/upper 50s.  Overnight Thu into Fri upto an inch of rain.   Colder Saturday - warmer Sunday- then back down Mon - tue before warming Chirstmas eve.  Overall looking warmer between Christmas and the 30th with strong nationwide ridge perhaps a day in there that approach 60 / record high?.  Colder air just to the north and the warmest is to the south west.   Still would watch the period 12/30-31. 

 

Wash, rinse, repeat! Same holidays pattern as always!

[NEG NAO]

45 minutes ago, SACRUS said:

29 / 21 warm the next 3 days Wed - Fri with perhaps some of the warmest areas touching or close to 60 on Friday, otherwise mid/upper 50s.  Overnight Thu into Fri upto an inch of rain.   Colder Saturday - warmer Sunday- then back down Mon - tue before warming Chirstmas eve.  Overall looking warmer between Christmas and the 30th with strong nationwide ridge perhaps a day in there that approach 60 / record high?.  Colder air just to the north and the warmest is to the south west.   Still would watch the period 12/30-31. 

 

With the NAO negative - the WPO Negative and MJO hanging around somewhere in Phase 8 - how do you get anywhere close to 60 ?