November 2025 OBS Discussion

[Sundog]

21 minutes ago, FPizz said:

What is NYC's average high temps for Nov 27-30th?  What does the Euro say those 4 days are supposed to be?  My work comp blocks weatherbell so I can't see it.  I know you're good looking up data though, so can you fill me in?  I was thinking it showed a bit below normal temps but maybe that changed.

The 28th at the park averages 50/39

[Sundog]

0z Euro was pretty cold for Thanksgiving weekend in NYC

Mid 40s for Thanksgiving, low 40s for Black Friday, mid 30s for Saturday. 

[eduggs]

Wow that's an historic trof across the west coast on the 12z CMC in the long range. I've noticed ULLs are forming and deepening right along the west coast this fall and then tracking southward along the full length of the California coastline. If you loop 500mb it's been happening and is forecast to happen over and over. I feel like this tendency was noticed the past two winters. And sure, ULLs getting stuck in the southwest has been going on forever. But this recent propensity seems more pronounced and repetitive than in the past.

Does anyone know why this is happening? Is it some kind of frictional effect or landmass-Ocean interface effect... maybe combined with Pacific Ocean temperatures and a strong Pac Jet? Or is this typical upper- & mid- level behavior and I've just never noticed it before?

[eduggs]

ChatGPT has some interesting theories to explain the repetitive ULLs following the CA coast. Its response was lengthy so I've summarized it below. I can't support or refute the validity of any of these potential mechanisms. ChatGPT further suggested that we are in a quasi-stable continental pattern. And in support of that, to my eye, the forecasted mean jet at day 15 does look roughly similar to its pattern and position over the past few days...

• Persistent Coastal Trough / Blocked Jet Stream

  • A semi-stationary trough off the West Coast creates a “corridor” that repeatedly guides ULLs southward.

  • Blocking patterns upstream (central/west Pacific ridging) prevent the flow from progressing eastward, so the same pathway persists.

• Cutoff Lows + Weak Steering Flow

  • ULLs becoming cut off from the main jet move slowly and tend to drift along the coastline where steering currents are weak but coherent.

  • Once one cutoff forms, subsequent ones often follow similar tracks.

• Coastal Waveguide Effect

  • Sharp land–ocean contrasts and California’s north–south coastline help steer shallow upper-level systems parallel to the coast.

  • The long coastline supports a “channeling” effect for southward-moving lows.

• North Pacific SST / PDO Influence

  • Negative PDO–like SST patterns (colder near CA, warmer farther west) promote troughing off the West Coast.

  • This anchors the mean storm-track/upper-level pattern in a coastal position.

• Weak La Niña Teleconnection

  • Current La Niña is weak, so typical ENSO storm-track signals (often more northerly) are not dominant.

  • With ENSO influence muted, other mid-latitude patterns can take over and become unusually persistent.

• Seasonal Transition Effects

  • Autumn jet-stream reorganization makes the atmosphere more prone to amplified and sticky patterns.

  • Early-season troughs are more likely to become cut off and recur along similar paths.

[SACRUS]

 

Records:

Highs:

EWR: 73 (1931)
NYC: 74 (1900)
LGA: 69  (1991)
JFK: 66 (2020)

Lows:

EWR: 18 (1987)
NYC: 16 (187 9)
LGA: 20 (1987)
JFK: 19 (1987)


Historical:

 

1798 - A four day storm was in progress in the northeastern U.S. The storm dropped a foot of snow on New York City and New Haven, and as much as three feet in Maine and New Hampshire. The snowstorm ushered in a long and severe winter, in some places the ground remained covered with snow until the following May. (David Ludlum)Northeastern States from November 19th to the 21st:
The infamous Long Storm sweeps across the the northeastern US spreading deep snow from Maryland to Maine. The storm dumps a foot of snow on New York City and New Haven, and as much as three feet on Maine and New Hampshire. Storm opens the famous Long Winter of 1978-99 which continues to drop snow on the region as late as May.
(Ref. WxDoctor)

1876: Boston, Massachusetts on the 20th and 21st had 5.43 inches of rain the greatest 24 hour precipitation for November. (Ref. NOAA Boston Weather Events)

1900: 79° the peak of a 6-day heat wave from 18th -23rd at WBO, Baltimore also 79° (Ref. Washington Weather Records - KDCA)

1924: Boston, MA. ended their longest period with no precipitation at 44 days. (Ref. Wilson Wx. History)

1967 - Excessive rains in southern California caused the most severe flooding and the most damaging mmud slidesin 33 years. Downtown Los Angeles received eight inches of rain, and 14 inches fell in the mountains. (David Ludlum)

1977: Arctic high pressure with an upper level trough brought record cold from the northern Rockies to the Pacific Northwest. Record low temperatures for the date included: Hardin, MT: -30° , Boulder, MT: -25°, Butte, MT: -24°, Wisdom, MT: -21°, Billings, MT: -18° (high was only 5 above), Sheridan, WY: -17°, Lander, WY: -14°: Tied, Rapid City, SD: -7°, Yakima, WA: 6°, Salt Lake City, UT: 7°, Olympia, WA: 11° and Seattle, WA: 21°. In contrast, Brownsville, TX set a record high with 89°. (Ref. Wilson Wx. History)

1979: The Upper Plains was hit with heavy snow through the 22nd as the storm raced northeast into Canada. Snowfall totals were in the 6 to 13 inch range with generally lesser amounts across northwest Iowa and southwest Minnesota. Sioux Falls, SD reported the highest storm total at 13 inches. Sioux Falls' 24-hour total through the 22nd of 11.8 inches is the heaviest 24-hour snow total in the month of November on record for the city. Moderate winds of 20 to 35 mph made travel difficult at times, but nowhere near as bad as a classic Dakota ground blizzard. Across the Rockies, some storm totals included: Wheatland, WY: 30 inches, Cheyenne, WY: 25.6 inches, Kimball, NE: 17 inches and 12.8 inches at Scottsbluff, NE. In contrast, on the west coast, Quillayute, WA set a record high with 60°. (Ref. Wilson Wx. History)
 

1985 - Hurricane Kate made landfall during the evening hours near Mexico Beach, FL. Wind gusts to 100 mph were reported at Cape San Blas FL. It was the latest known hurricane to hit the U.S. so far north. (The Weather Channel)

1987 - Squalls in the Lower Great Lakes Region and the Upper Ohio Valley produced 14 inches of snow at Snowshoe WV, and nearly eight inches at Syracuse NY. Eleven cities in the eastern U.S. reported record low temperatures for the date. Record lows included 21 degrees at Pinson AL, 9 degrees at Syracuse NY, and 8 degrees at Binghamton NY. Gale force winds lash the Middle and Northern Atlantic Coast, and the strong northwesterly winds produced wind chill readings as cold as 30 degrees below zero. Winds gusting to 60 mph at Trumansburg NY toppled a chimney onto a nearby truck. (The National Weather Summary) (Storm Data)

1988 - High winds accompanied rain and snow in the northeastern U.S. Caribou ME received eight inches of snow in six hours, and Fort Kent ME was blanketed with a total of fourteen inches of snow. (The National Weather Summary) (Storm Data)

1989 - The storm which produced thunderstorms and high winds in the northeastern U.S. the previous day, produced snow and high winds in New England, with blizzard conditions reported in Maine. Winds gusted to 55 mph at Boston MA, and reached 58 mph at Augusta ME, and hurricane force winds were reported off the coast of Maine. Snowfall totals ranged up to 18 inches at Vanceboro ME, with 17 inches at South Lincoln VT. There were thirty-five sstormrelated injuries in Maine. (The National Weather Summary) (Storm Data)

1992: The November 21st – 23rd tornado outbreak was the 3rd largest outbreak in recorded history and one of the longest continuous outbreaks ever recorded. There was no break in tornado activity from 1:30 pm on the 21st when the tornadoes started in Texas until 7:30am on the 23rd, when the last tornadoes lifted in North Carolina. On this date, severe thunderstorms spawned 6 tornadoes within 70 minutes in the Houston metro area in Texas. At one time, there were three on the ground in Harris County. The strongest, an F4, tracked 20 miles through the eastern suburbs of Houston destroying 200 homes and damaging 1,000 more. In total, 23 tornadoes struck Mississippi and Alabama. An F4 tornado killed 12 people on a 128-mile track through 7 Mississippi counties. The deadliest tornado of 1992, an F4 tornado killed 12 people on a 128 mile track through 7 counties in Mississippi, one of the bodies was blown a quarter mile into a tree. (Ref. AccWeather Weather History)

1996: Brutal cold invaded Montana bringing record low temperatures for the date including: Havre, MT: -27°, Shelby, MT: -25°, Cut Bank, MT: -23°, and Stanford, MT: -18°. In contrast, Corpus Christi, TX set a record high with 91°. (Ref. Wilson Wx. History)

1999: Forests across the east became tinderboxes, with up to 60,000 acres burned in the Appalachians. Moist air from the Pacific shifted farther north than usual, leaving the South and Southwest drier and warmer than normal. Crawfish farmers in Louisiana were feeling the effect as their ponds were drying up. Hunters also reported that waterfowl were bypassing dry central Louisiana in favor of coastal areas. In contrast, the first significant snow of the season struck the Colorado Rockies. Snowfall totals included: Bailey, CO: 16 inches, Evergreen, CO: 13 inches, North Turkey Creek, Genesee, Morrison and Sedalia, CO: 12 inches, Conifer and Evergreen, CO: 11 inches, Louisville, CO: 10 inches, Brighton, Broomfield and Denver, CO: 9 inches and Arvada, Castle Rock and Eldorado Springs, CO with 8 inches. (Ref. AccWeather Weather History)

2004: Southern California from November 21st to 22nd: Up to 3 feet of snow blankets Southern California's San Gabriel and San Bernardino mountains east of Los Angeles. and even whiten nearby desert areas. (Ref. WxDoctor)
 

[donsutherland1]

28 minutes ago, eduggs said:

ChatGPT has some interesting theories to explain the repetitive ULLs following the CA coast. Its response was lengthy so I've summarized it below. I can't support or refute the validity of any of these potential mechanisms. ChatGPT further suggested that we are in a quasi-stable continental pattern. And in support of that, to my eye, the forecasted mean jet at day 15 does look roughly similar to its pattern and position over the past few days...

• Persistent Coastal Trough / Blocked Jet Stream

  • A semi-stationary trough off the West Coast creates a “corridor” that repeatedly guides ULLs southward.

  • Blocking patterns upstream (central/west Pacific ridging) prevent the flow from progressing eastward, so the same pathway persists.

• Cutoff Lows + Weak Steering Flow

  • ULLs becoming cut off from the main jet move slowly and tend to drift along the coastline where steering currents are weak but coherent.

  • Once one cutoff forms, subsequent ones often follow similar tracks.

• Coastal Waveguide Effect

  • Sharp land–ocean contrasts and California’s north–south coastline help steer shallow upper-level systems parallel to the coast.

  • The long coastline supports a “channeling” effect for southward-moving lows.

• North Pacific SST / PDO Influence

  • Negative PDO–like SST patterns (colder near CA, warmer farther west) promote troughing off the West Coast.

  • This anchors the mean storm-track/upper-level pattern in a coastal position.

• Weak La Niña Teleconnection

  • Current La Niña is weak, so typical ENSO storm-track signals (often more northerly) are not dominant.

  • With ENSO influence muted, other mid-latitude patterns can take over and become unusually persistent.

• Seasonal Transition Effects

  • Autumn jet-stream reorganization makes the atmosphere more prone to amplified and sticky patterns.

  • Early-season troughs are more likely to become cut off and recur along similar paths.

Interesting. You should ask it to follow up with links to related scientific papers on which its assessment was based. 

[NorthShoreWx]

28 minutes ago, donsutherland1 said:

Interesting. You should ask it to follow up with links to related scientific papers on which its assessment was based. 

I'd also like to see the original wording of the query, just to further my understanding of how the bot responds.

[eduggs]

6 minutes ago, NorthShoreWx said:

I'd also like to see the original wording of the query, just to further my understanding of how the bot responds.

It was a quick and casual prompt:

ULLs have been following the full coastline of CA, all the way and sometimes past the southern tip. This has been recurring every few days for the past few weeks and current model forecasts out to 15 days into the future show the same recurring feature... I've never seen this feature so repetitive before and I'm trying to figure out why.

...followed by a request to provide a concise summary.

[SACRUS]

 

 

Nov Dep through the 2/3 (20th)

EWR: +0.2
JFK: -0.5
NYC: -1.2
LGA: -1.5

[eduggs]

40 minutes ago, donsutherland1 said:

Interesting. You should ask it to follow up with links to related scientific papers on which its assessment was based. 

It responded that it didn't use any papers.

My earlier responses were based on:

• foundational meteorological knowledge (jet dynamics, cutoff-low behavior, coastal steering, ENSO teleconnections, North Pacific climatology),

• plus the real-time information I retrieved via your previous queries.

[SACRUS]

 

Models push trough back into the WC with ridging poking east around Dec 1.  Likely transient.  Cold building to the northwest

 

[steve392]

7 hours ago, psv88 said:

It’s pretty good. Can get boring after a while though, so sometimes I go in

These last 2 days were only virtual days. Next week new job training actually starts in Kearny, nj. 

[donsutherland1]

A generally milder than normal pattern will likely continue through next Wednesday. However, exceptional warmth appears unlikely. The closing days of November will likely turn colder.

Meanwhile, today will be Central Park's 1,392nd consecutive day without daily snowfall of 4" or more. The record of 1,394 days was set during February 22, 1929 through December 16, 1932. That stretch ended with 6.7" daily snowfall on December 17, 1932.

The ENSO Region 1+2 anomaly was -0.7°C and the Region 3.4 anomaly was -0.7°C for the week centered around November 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.16°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 +26.47 today. 

The preliminary Arctic Oscillation (AO) was +0.707 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied 83% probability that New York City will have a cooler than normal November (1991-2020 normal). November will likely finish with a mean temperature near 46.6° (1.4° below normal). 

Supplemental Information: The projected mean would be 1.1° below the 1981-2010 normal monthly value. 

 

[MANDA]

For those of you that like to reminisce:

Some good memories here.

If you watch till the end what do you prefer?  The information overload of today or the way is used to be.  For me the information of today is great but there was something "magical" as a kid (70's and 80's) with just evening newscasts, scanning the radio dial (1010, 880, 1130) and my little radio shack weather cube.  Personally I'm glad I grew up in that era.

If you are not old enough to remember any of that you missed out on great times in my opinion.

Who can forget the Winter Storm Watch being downgraded to a Travelers Advisory????  Always a great disappointment.

 

[IrishRob17]

45 minutes ago, MANDA said:

For those of you that like to reminisce:

Some good memories here.

If you watch till the end what do you prefer?  The information overload of today or the way is used to be.  For me the information of today is great but there was something "magical" as a kid (70's and 80's) with just evening newscasts, scanning the radio dial (1010, 880, 1130) and my little radio shack weather cube.  Personally I'm glad I grew up in that era.

If you are not old enough to remember any of that you missed out on great times in my opinion.

Who can forget the Winter Storm Watch being downgraded to a Travelers Advisory????  Always a great disappointment.

 

Didn’t matter if it was the NWS broadcast or a radio station but the excitement when the forecasted accumulations jumped up! I agree on the info overload nowadays, it’s not nearly as exciting. 

[bluewave]

19 hours ago, TheClimateChanger said:

I thought there was supposed to be a big cold snap around Thanksgiving?

The real cold on Thanksgiving will be closer to Siberia. You have to give those people credit for surviving in such a cold environment. Luckily, their energy bills to heat their units are relatively low compared to what we would be paying if it ever got that cold here. 
 

 

 

[MJO812]

1 hour ago, bluewave said:

The real cold on Thanksgiving will be closer to Siberia. You have to give those people credit for surviving in such a cold environment. Luckily, their energy bills to heat their units are relatively low compared to what we would be paying if it ever got that cold here. 
 

 

 

I always watch videos of Siberia lol

[bluewave]

4 minutes ago, MJO812 said:

I always watch videos from Siberia lol

The videos from Svalbard are pretty wild also. 

 

 

[MJO812]

19 minutes ago, bluewave said:

The videos from Svalbard are pretty wild also. 

 

 

Yep already saw that.  Insane how they live.

They are the true winter weenies 

[ILoveWinter]

2 minutes ago, MJO812 said:

Yep already saw that.  Insane how they live.

They are the true winter weenies 

My cousin and her fiancé were there last winter and he proposed to her under the northern lights! They said it was a truly amazing and unique place.

[weathermedic]

.29 in the bucket at my station 

[nycwinter]

3 hours ago, MJO812 said:

I always watch videos of Siberia lol

even russia is not as cold as it was 30 years ago.

[FPizz]

1 hour ago, weathermedic said:

.29 in the bucket at my station 

.25" here.  

[weatherpruf]

6 minutes ago, nycwinter said:

even russia is not as cold as it was 30 years ago.

consensus is we aren't having much of a winter here this year, so there, i'm glad the experts got it off their chests.....and actually haven't seen much of one since 2021, which was pretty snowy, and seems ignored around here. i guess there were other things in the news....the local reservoir is down to a trickle, though it is not used for drinking anymore and is scheduled for dredging and redevelopment. that would be the clark reservoir, subject of much controversy these days.

[SACRUS]

 

50 / 48 drying out a bit and slowly clearing later.   Warmer 11/22 - 11/26 then below 11/27 - 11/30 before moderating warmer to open next month.  Appears a back and forth between the cold and warmth and in between at times.

 

 

[SACRUS]

Records;


Highs:

EWR: 72 (1931)
NYC: 72 (1931)
LGA: 69 (1940)
JFK: 67 (1983)


Lows:

EWR:  17 (2018)
NYC: 13 (1880)
LGA: 19 (2018)
JFK: 18 (2018)

Historical:

 

1641 - An observer at Boston, MA, recorded a great tempest of wind and rain from the southeast all night, as fierce as a hurricane, and thereupon followed the highest tide which we have seen since our arrival here . (David Ludlum)

1720: New York City had an early severe cold snap. Doctor Colden wrote "my ink freezes as I write". (Ref. Wilson Wx. History)

1957 - Extremely destructive Santa Ana winds blew from Oxnard to San Diego and inland parts of southern California. The high winds produced a 28,000 acre brush fire on a 40-mile front west of Crystal Lake. People were ordered off streets in some areas due to flying debris. (21st-22nd) (The Weather Channel)

 

1961: Hailstones 4 inches in diameter severely damaged all roofs of the region located about 25 miles southwest of Bradley Texas. Most of the area was ranch land so damage to property was small. However, a lot of dead deer were found in open areas literally beaten to death by the hail. (Weather Guide Calendar with Phenomenal Weather Events 2007 Accord Publishing, USA)

1979: One last record from the 1979 winter storm: Cheyenne, WY’s deepest snow cover on record was recorded on this day with a snow depth of 26 inches. (Ref. Wilson Wx. History)

1983: A snowstorm dumped 2 to 6 inches of snow over a large part of northwest, southwest and central Iowa. In addition, freezing rain accompanied the snow in some locations. The result was extremely hazardous roads and highways, with a glaze of ice underneath the snow. Power lines were downed by the ice, and many rural communities lost power for hours. Portland, OR received their 25th straight day of rain. (Ref. Wilson Wx. History)

1984: A strong low pressure system developed east of Florida, and coupled with a high pressure to the northwest created a strong pressure gradient that led to gale force winds along the east coast. As the low moved slowly north heavy rains of up to 7 inches fell over south Florida. Palm Beach, FL received 4 inches of rain in 4 hours. There was extensive coastal flooding and beach erosion with many structures damaged or destroyed. Fishing piers and seawalls were damaged or destroyed. Damage ran into the millions and was confined to the shore except where heavy rain in the south caused local flooding. A man was killed when he stepped on a downed power line.  (Ref. Wilson Wx. History)

1987 - Eight cities in the eastern U.S. reported record low temperatures for the date. Elkins, WV, reported a low of 5 degrees above zero. Gale force winds continued along the Northern Atlantic Coast. (The National Weather Summary)

1988 - Wet and windy weather prevailed across the western U.S., with heavy snow in some of the higher elevations. Winds gusted to 62 mph at Vedauwoo WY, and reached 75 mph at Tillamook OR. Shelter Cove CA was drenched with 4.37 inches of rain in 24 hours. (The National Weather Summary) (Storm Data)

1989 - Strong northerly winds produced squalls along the shore of Lake Michigan, with heavy snow in extreme southeastern Wisconsin. Milwaukee WI received nine inches of snow, and in Racine County there were more than one hundred automobile accidents. (The National Weather Summary) (Storm Data)

1992: 45 tornadoes touched down in the Tennessee and Ohio Valleys. Georgia was hard hit with two F4, one F3 and three F2 tornadoes that killed 6 people and injured 144. Indiana had a total of 15 tornadoes on this day to set a record for an outbreak in November and for the month of November. One, an F4 multiple-vortex type, cut a 22-mile path through extreme southeastern Indiana and northern Kentucky. This tornado debunked the myth that twisters don't cross rivers, as this devastating tornado crossed the Ohio River twice. Indiana had a total of 15 tornadoes on this day to set two state records, the largest November tornado outbreak and the most tornadoes in November. This tornado outbreak made a significant contribution to what was to become the biggest November ever for the U.S. in terms of number of tornadoes. (Ref. AccWeather Weather History)

1993: A major, slow-moving snowstorm affected much of South Dakota from this date through the 27th producing prolific amounts of snow. The heaviest snow amounts in the 2 to 3 foot range occurred in northeast South Dakota and in the northern Black Hills. Storm total snowfall amounts included: 37.7 inches at Lead, 31.8 inches at Westport, 28 inches at Britton, and 25.3 inches at Aberdeen. The 25.3 inches at Aberdeen was a single storm snowfall record and it made this November the snowiest November on record in Aberdeen. Much of the eastern third of South Dakota was brought to a standstill on the 24th bringing an early start to the Thanksgiving Holiday. The weight of the snow collapsed numerous structures in northeast South Dakota. Strong northwest winds and cold temperatures followed the storm plunging wind chill values to -50°. Snowfall across northwest Iowa and southwest Minnesota for the storm was generally 5 to 9 inches. (Ref. Wilson Wx. History)

1999: The first significant snowstorm of the year pounded Colorado with up to 20 inches of snow at Fairplay southwest of Denver and 9 inches in Denver. The snowstorm reduced visibilities, causing a massive 83 car pileup on I-70 west of Denver. Two people were killed and 30 were injured in the giant accident. The first blast of wintry weather followed unusually warm weather that had Denver averaging 12 degrees above normal for the first 3 weeks of the month.  (Ref. AccWeather Weather History)

2003: Record snow falls across the southern Yukon as a Pacific storm system moved inland. The weather station on the Klondike Highway recorded 8.7 inches of snow. Mayo Airport measured 8.3 inches, the greatest daily November snowfall since records began in 1926 and the fourth snowiest day ever. A few locations out west reported record low temperatures for the date including: Spokane, WA: -5°, Madera, CA: 27°, Merced, CA: 28°, Hanford, CA: 29° and Redding, CA: 29°-Tied. St. Paul, AK tied their record high with 43°. (Ref. Wilson Wx. History)

 

[uofmiami]

0.26” for Syosset & 0.23” for Muttontown. 

[NorthShoreWx]

0.26" north Smithtown

 

[IrishRob17]

.23 up here, anyone who better the over is cashing in, thought most of it was going to be to my south but what do those models know anyway?