December 2025 OBS and Discussion

[Brasiluvsnow]

41 minutes ago, donsutherland1 said:

It will be increasingly cloudy and cold tomorrow. Light to moderate snow will overspread the region tomorrow night. The New York City area will see a general 1"-3" snowfall with a few locally higher amounts.

In the wake of the system, Sunday and Monday will be blustery and cold days. High temperatures will likely wind up below freezing.

The WPO is falling toward severely negative levels. That will likely contribute to the December 10-20 period being colder than normal overall. Moderation is possible late in the period as the WPO begins to rise.

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 -0.2°C and the Region 3.4 anomaly was -0.5°C for the week centered around December 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.27°C and the ENSO Region 3.4 anomaly has averaged -0.65°C. La Niña conditions will likely continue through at least mid-winter.

The SOI was -4.67 today. 

The preliminary Arctic Oscillation (AO) was +0.811 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied near 89% probability that New York City will have a cooler than normal December (1991-2020 normal). December will likely finish with a mean temperature near 34.8° (4.3° below normal). 

Supplemental Information: The projected mean would be 2.6° below the 1981-2010 normal monthly value. 

 

Thank You Don as that is EXACTLY what I was saying prior to my posts being pulled but you said it much more eloquently ,, enjoy the snow tomorrow night folks

[jimbo073]

11 hours ago, Nibor said:

That little band of snow last night packed a punch.

Yes we had that in Hoboken too

 

[Roger Smith]

<<< LOWEST DECEMBER MAXIMUM TEMPERATURES >>>

Rank __ Year __ Temp 

_ 01 ____ 1917 __ 47 (1st) 

_t02 ____ 1872 __ 49 (15th), 1876 _ 49 (13th), 1880 _ 49 (5th), 1890 _ 49 (3rd), 1926 _ 49 (14th)

_t07 ____ 1874 __ 51 (3rd), 1882 _ 51 (6th), 1904 _ 51 (28th)

_t10 ____ 1909 __ 53 (6,13,14), 1944 _ 53 (8th), 1955 _ 53 (3rd), 1989 _ 53 (31st) (was 2nd lowest 48 before that)

_t14 ____ 1903 __ 54 (13th), 1910 _ 54 (30th), 1945 _ 54 (8th), 1997 _ 54 (16th)

_t18 ____ 1871 __ 55 (23rd), 1883 _ 55 (8th), 1886 _ 55 (24th), 1888 _ 55 (17th), 1902 _ 55 (22nd)

___ ___ t18 __ 1933 _ 55 (25th), 1958 _ 55 (5th), 1963 _ 55 (8th), 1976 _ 55 (7th), 1985 _ 55 (2nd, 24th),

___ ___ t18 __ 1995 _ 55 (3rd), 2005 _ 55 (24th)

_t30 ____ 1907 __ 56 (10th), 1929 _ 56 (14,15,19), 1935 _ 56 (9th), 1974 _ 56 (8th), 1977 _ 56 (14th)

_t35 ____ 1870 __ 57 (4th), 1894 _ 55 (12th), 1896 _ 57 (13th), 1898 _ 57 (30th), 1907 _ 57 (23rd), 

___ ___ t35 _ 1915 _ 57 (18th), 1922 _ 57 (1st), 1943 _ 57 (9th), 1959 _ 57 (13th)

_t44 ____ 1887 __ 58 (11th), 1892 _ 58 (8th), 1913 _ 58 (3rd), 1920 _ 58 (14th)

___ ___ _t44 _ 1925 _ 58 (5th, 6th), 1930 _ 58 (1st), 1942 _ 58 (2nd), 1947 _ 58 (3rd), 1948 _ 58 (13th), 

___ ___ _t44 _ 1961 _ 58 (5th), 1981 _ 58 (2nd), 2003 _ 58 (13th), 2019 _ 58 (10th)

_t57 ____ 1877 __ 59 (20th), 1884 __ 59 (31st), 1893 __ 59 (16th), 1899 _ 59 (11th,12th), 1900 _ 59 (24th),  

___ ___ t57 _ 1905 _ 59 (3rd), 1906 _ 59 (31st), 1921 _ 59 (1st)1952 _ 59 (11th), 1957 _ 59 (20th), 

___ ___ t57 _ 1972 _ 59 (31st), 1983 _ 59 (12th, 13th), 1986 _ 59 (3rd), 2004 _ 59 (8th, 23rd)

================================================

Up to 1910, it was normal for December to fail to break 59 F, it happened in 30 of 42 years (71%). 

From 1911 to 1960 it happened 23 more times (46%).

From 1961 to 2000 it happened 13 more times (33%). 

From 2001 to 2024 it happened 4 more times (17%). (2003,04,05,19)

Overall it has happened 70 times (45%). 

The interval 2006 to 2018 (13 Decembers) is the longest interval without a sub-60 maximum value.

Before that, the longest such interval was ten years (1964 to 1973) and before that six years (1936 to 1941). 

The average value for all years is 60.3 F. Since 1961 the average is 62.2 F. Since 1990 it is 62.9 F. 

 

 

[steve392]

11 hours ago, Nibor said:

That little band of snow last night packed a punch.

What time did it hit?  Explains all the snow in Kearny. 

[MANDA]

8 hours ago, Picard said:

I'm in Sparta, and have been pretty satisfied with the winter weather so far, all things considered.  There has not been any big events - but several rounds of smaller events to make things festive.  My ground has been covered since last Tuesday because it's been so cold.  It's been nice to have a few small refreshers since then.

That said - we are still in a precip deficit out this way, so at some point I'm hoping for much bigger snows or a healthy dose of early spring rains.  

Picked up .7" snowfall last evening in persistent and at times heavy snow squalls.  Visibility on Route 80 at the height of things was horrendous with moderate to heavy snow at times and a gusty wind.  The salt water spray being kicked up onto the windshield was no help either.

The .7" last evening boosts my seasonal total to 2.3".  On a nickle and dime ride to 3".

Lots of brine being sprayed today.  As early as 9am on Route 10 out this way.  Just don't see how it helps to spray this stuff 36 hours before an event is scheduled to begin.  Wouldn't it be worn out by all the traffic over 36 hours??  I don't know, just asking.

[Volcanic Winter]

Holding steady at 15F here, nice cold ground ahead of this little event. Looks like SEMA is gonna pick up the most in NE and I’m happy for those guys, they’ve been getting screwed as much as the NYC area lately. 

Hopefully this is a nice little event for everyone. I think LI down to my area should do pretty solid, hopefully it ticks up for NYC also. 

[SnoSki14]

15 hours ago, MJO812 said:

Cold Christmas on the Euro with some type of storm. 

Hopefully the cold runs continue

Strong gradient like pattern. Some models showing Arctic ridging. If the gradient can slip south every now and then for latter Dec and Jan then it could get interesting. 

I'd feel better being north though 

[MJO812]

1 hour ago, SnoSki14 said:

Strong gradient like pattern. Some models showing Arctic ridging. If the gradient can slip south every now and then for latter Dec and Jan then it could get interesting. 

I'd feel better being north though 

Way too much cold air to the north to be a blowtorch pattern

[bluewave]

One more Arctic outbreak before the pattern moderates.

 

 

[TJW014]

Beautiful sunrise. 

Red sky in the morning, a sailor's warning. 

Definitely has that "it's gonna snow" feeling in the air

[MJO812]

3am update from NWS.  A little more snow on the south shore of NYC and Long Island . 

[PhiEaglesfan712]

41 minutes ago, MJO812 said:

3am update from NWS.  A little more snow on the south shore of NYC and Long Island . 

Take it down a little south: 

This is really the first time since the January 28-29, 2022 snowstorm that we got this type of storm track, where there is more snow towards the coastal areas.

[donsutherland1]

Overnight runs have added some QPF to the New York City region into central Westchester County and southern Fairfield County. Ratios will probably be 11:1 to 13:1 across a good part of the region.

Taking all this into consideration, my thinking is that the New York City area, including its nearby northern  suburbs will see a general 2"-4" snowfall. A portion of New Jersey and Long Island could see higher amounts, especially as some Atlantic moisture could become involved as the system departs e.g., Islip could wind up with a 3"-5" snowfall.

Recent Snowfall Thresholds for New York City:

Storm total Snowfall:
Last 1" or above snowfall: February 11-12, 2025: 1.6"
Last 2" or above snowfall: February 8-9, 2025: 3.1" 
Last 4" or above snowfall: January 28-29, 2022: 8.5"

Daily Snowfall:
Last 1" or above snowfall: February 11, 2025: 1.2"
Last 2" or above snowfall: February 8, 2025: 3.0"
Last 4" or above snowfall: January 29, 2022: 7.3"

Given the timing of the snow's onset, today will very likely extend the record streak without 4" or above snowfall to 1,414 consecutive days for New York City.

Farther south, Philadelphia is in line for a 3"-6" snowfall. The last time Philadelphia saw a 4" or greater snowstorm was January 19, 2024 when 4.6" fell. Philadelphia's last 6" or above snowstorm occurred during January 28-29, 2022 when 7.5" blanketed the city.

[psv88]

18 this morning 

[bluewave]

49 minutes ago, PhiEaglesfan712 said:

Take it down a little south: 

This is really the first time since the January 28-29, 2022 snowstorm that we got this type of storm track, where there is more snow towards the coastal areas.

At least a step in the right direction but the KU track still remains elusive.