January 2026 OBS and Discussion

[Rjay]

There's no such thing as a jinx in weather.  Thread started. 

[MANDA]

What are we thinking for ratios on this next storm?  

[Winterweatherlover]

Too tired from tracking the last one for this lol. These type of storms also drive me nuts to track because they usually disappear at some point on the models. It obviously has massive potential.

[MANDA]

Melted total for storm just completed 1.55".  Snowfall 13.5".  Storm averaged ratio 8.71/1.  Started out at 20:1 then fell as the event progressed.

Temperature never got above 10 degrees through the entire event.  Hopefully this puts an end to the "it is so cold ratios will be beyond words" stuff.   Cold surface temperatures are not the driving factor in ratios.  Look aloft.  

[Ridgewoodweather125]

What is timing roughly for this storm? Trying to figure out if a flight into EWR first thing Sunday morning still seems feasible if the storm does happen


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[Rjay]

7 minutes ago, Ridgewoodweather125 said:

What is timing roughly for this storm? Trying to figure out if a flight into EWR first thing Sunday morning still seems feasible if the storm does happen


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Saturday night into Sunday but it's 5-6 days away

[Ridgewoodweather125]

3 minutes ago, Rjay said:

Saturday night into Sunday but it's 5-6 days away

Thank you; thinking I may book a flight late Saturday just as protection if it ends up being needed 

[EasternLI]

57 minutes ago, Rjay said:

There's no such thing as a jinx in weather.  Thread started. 

Nice! Rjay threads are usually good luck too lol 

[WeatherGeek2025]

50 minutes ago, MANDA said:

What are we thinking for ratios on this next storm?  

15:1

[North and West]

Cue the obligatory Kylo Ren "More" GIF.  Although N&W may want to hold it until later in the week with the model runs.
 
 

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[coastalplainsnowman]

1 hour ago, Rjay said:

Saturday night into Sunday but it's 5-6 days away

Shoot, Sunday is February.  Sun angle is definitely going to play a role in this one.

[Mr. T.]

Been a pretty long time since I've seen a possible benchmark setup. I'm down for it!

Edit: keep forgetting we have a thread for this threat now.

[Nutjob18]

Upton with 20- 30 percent chance of 6 inches or more

https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=AFDOKX&e=202601261832

Deterministic and ensemble models show a piece of energy breaking 
off the polar vortex and shifting into the Southeast this weekend 
before lifting off the Mid-Atlantic coast. This would then help 
develop a surface low emerging off the Carolina coast during 
Saturday and strengthen the storm as it heads northeast, perhaps 
approaching the 40N/70W benchmark at some point Sunday or Sunday 
night.

Did not deviate from NBM PoPs (20-30%) from Saturday night through 
Sunday night. Too early to have much confidence with the probability 
of occurrence and certainly with any details of the storm this many 
days away. With that said, NBM shows a 20-30% chance of at least 6 
inches of snow across the area for the event. Additionally, there is 
at least moderate to high confidence that temperatures would be cold 
enough to support snow at the start of the event.

[hooralph]

WOW

[jm1220]

13 minutes ago, hooralph said:

WOW

Imagine it a week from now. 

[EastonSN+]

24 minutes ago, Weather Will said:

WB 12Z EPS compared to 0Z; east shift but we have time to reek back in.

From the MA forum definitely shifted east from 0z. 

[gravitylover]

Interesting expanding area of light snow happening. It's been getting progressively heavier for the last 20 minutes and is starting to coat things now. Pretty cool.

[donsutherland1]

New York City experienced its biggest snowstorm in nearly five years when 17.4" accumulated during January 31-February 3, 2021. 

Arctic air is now returning to the region. Highs will then be mainly in the lower 20s through Friday. Tomorrow could again see highs top out in the teens in New York City. That could happene again later in the week. The last winter with more than one high in the teens was Winter 2018-19 when there were two such days. 

Moreover, New York City has the potential to see the temperature dip into the single digits for lows on or more days during this period. Some snow flurries or snow showers are possible Thursday night into Friday morning. 

Additional snow is possible on Sunday. A number of ensemble members hint that the snowfall could be significant. It's too soon to be certain about details. 

A large storm would be historic. For reference, New York City has seen just one 10" or above snowstorm one week or less following a 10" or above snowstorm: February 3-4, 1926 (10.4") and February 9-10, 1926 (12.4"). The shortest interval between 10" or above daily snowfalls is 14 days: March 2, 1896 (10.0") and March 16, 1896 (12.0"). Records go back to 1869.

Overall, January 20th-February 3rd will likely be the coldest and perhaps snowiest two-week period this winter. The forecast WPO-/EPO-/AO-/PNA+ pattern is typically the coldest pattern in January and among the coldest during the first half of February. A persistently positive PNA will have above climatological risk of moderate or significant snowfalls. 

For perspective, the coldest two-week period this winter prior to January 20th was January 3-16, 2026 and January 4-17, 2026 with a mean temperature of 30.3°. The snowiest two-week period was December 14-27, 2025 when 7.2" of snow fell. Already, snowfall since January 20th has surpassed that figure.

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 January 14. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.48°C and the ENSO Region 3.4 anomaly has averaged -0.68°C. La Niña conditions will likely continue into at least late winter.

The SOI was -9.93 today. 

The preliminary Arctic Oscillation (AO) was -3.462 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a cooler than normal January (1991-2020 normal). January will likely finish with a mean temperature near 30.3° (3.4° below normal). 

Supplemental Information: The projected mean would be 2.3° below the 1981-2010 normal monthly value. 

 

[qg_omega]

7 hours ago, MANDA said:

Storm total snowfall and QPF:

Click to enlarge maps.

QPF clearly over performed even the wettest guidance, in some cases by 1/2" or more depending on the location and model of choice.  The models ticking up the QPF as we got closer to the event start time was clearly on the right track though.

Quick spot checks on ratios and nothing to write home about when averaged out over the storm duration....roughly 8:1 to 12:1 along the I78-I80 corridor and east across the city and LI.  Just did a quick spot check.

I'd have to give a nod to the higher QPF totals for getting storm total snowfall to near or over the high end ranges of the forecast.  If they had been more or less as modeled in the 1 to 1.25" and taking the actual ratios into consideration storm total snowfall would have been closer to the lower end of the forecast ranges.  Just my 2 cents.

 

Imagine if we had good ratios for this storm…started off well which is why the major sites almost hit a foot but ratios quickly went under 10:1 and then closer to 6:1…. Even at 10:1 average we would have seen widespread 20+ inches

[lee59]

Ice breakers will be heading up the Hudson.

[Roger Smith]

Turns out that NYC tied the daily precip record of 1.80" for Jan 25, the earlier mentioned 1.82" includes .02" after midnight apparently. So it's a tie with the 1978 rainstorm component of the Great lakes blizzard/superstorm low that gave some places 15-30 inches of snow overnight into 26th Jan (1978). I will adjust any tables I have posted at end of month giving NYC a chance to settle their accounts, sometimes what you see one day is not there forever. 

Don, here's a challenge, I could work on this too, but what is the largest differential between a record snowfall and record precip or any precip on the 10:1 basis? I realize yesterday's storm was bulked up for precip by sleet that was also in the snowfall total. In Canadian climate records this might appear something like 0.20" rain and 12" snow for 1.80" precip. Canadian climate records show separate rain and snow amounts for every day and they seem to handle sleet a bit differently than U.S. practice. I am aware of one case where 40 mm of precip was really 10 cm of sleet but they give a 10 cm snow total for that case, and 30 mm rainfall. Part of the problem (if this can be described as a problem) is that Canadian observing practice was strictly 10:1 snow to precip untiil 1962 then changed to melt-it-down whatever-it-actually-was conversions after 1962. Thus if I look at some old storm record and it says 10.0" snow, 1.15" precip and 0.15" rain, I cannot say for sure whether that was rain, freezing rain, sleet melted down or whatever. 

Anyway, yesterday's differential was about 0.66" from 10:1, some values in Feb 1920 are definitely larger on a daily basis. 

[snywx]

11 minutes ago, qg_omega said:

Imagine if we had good ratios for this storm…started off well which is why the major sites almost hit a foot but ratios quickly went under 10:1 and then closer to 6:1…. Even at 10:1 average we would have seen widespread 20+ inches

Ratios were over 20:1 to start up here in OC. By mid-afternoon they were under 10:1. Finished with 1.67" L.E here imby

[Rjay]

Snowing again 

[steve392]

5 hours ago, hooralph said:

WOW

https://www.instagram.com/p/DT-7Ht6iTY4/?igsh=MXE3eDR0eWY5OGluNw==

 

Cool pics of icy Hudson too