December 2025 OBS and Discussion

[donsutherland1]

6 hours ago, Maestrobjwa said:

How do I get this for BWI? 

For Baltimore, the snowfall cases are far more mixed.

[FPizz]

55 minutes ago, EastonSN+ said:

TWC mentioned a few records can fall tomorrow morning w/r/t record lows. Bridgeport is one location. 17 is the current record there. Something to watch.

 

Tomorrow my forecast low is 13.  I have no clue what the record might be around here.

[forkyfork]

too much pacific energy keeping the pna ridge flattened and ruining an otherwise great pattern 

[BxEngine]

2 hours ago, Sundog said:

Were you the one that said +10 for October? 

Hes one of the kids that posts pessimistic shit this way when it inevitably happens, he can claim victory and also be mentally prepared for the sadness that people feel when they dont get what they actually want. And if we happen to get snow they wont acknowledge the incorrect posts, just move on and enjoy their snow they wanted while being doubly excited because they were pessimistic. Freud would have a field day in this forum.   

[EastonSN+]

31 minutes ago, FPizz said:

Tomorrow my forecast low is 13.  I have no clue what the record might be around here.

With snow cover to the north, may help multiple record lows. 

[donsutherland1]

For reference, New York City area locations where daily records could be challenged or broken on December 5th:

[jm1220]

1 hour ago, EastonSN+ said:

Courtesy of the MA forum. The MA beating us to the first accumulation would be fitting in the current cutter/suppressed period we are in. 

Perfectly fitting to go from raw nasty all rain in the upper 30s to cold/dry/suppressed garbage. Hopefully we can get something to turn the corner when it’s still cold enough here. The storms of course will come back when the cold retreats. 

[Brian5671]

3 minutes ago, jm1220 said:

Perfectly fitting to go from raw nasty all rain in the upper 30s to cold/dry/suppressed garbage. Hopefully we can get something to turn the corner when it’s still cold enough here. The storms of course will come back when the cold retreats. 

Or a clipper but those seem to be very rare the last 15-20 yrs

[jm1220]

Just now, Brian5671 said:

Or a clipper but those seem to be very rare the last 15-20 yrs

Last year we were able to get 1-2” small events right before Christmas, which was better than zilch but looks more likely we’re going to waste this cold for anything more substantial. Our best shot given the lightning fast pattern is likely something along those lines. An offshore redeveloper would probably form too late for us, and we can’t get the pattern to slow enough for a more meaningful s/w to turn the corner. I’m not optimistic for this cold snap to produce snowwise but we’ll see. 

[MJO812]

Phase 8 this week

Models are active. Just need to get it timed right. 

[psv88]

A shame Friday won’t work out. Cant believe mid Atlantic snows before us 

[EastonSN+]

7 minutes ago, yoda said:

 

Again courtesy of the MA forum.

Its the NAM so grain of salt at this range but would fit the last few years where the Delmarva schoold our area w/r/t %of average snowfall lol.

[Brian5671]

1 minute ago, psv88 said:

A shame Friday won’t work out. Cant believe mid Atlantic snows before us 

Same ol pattern.   Fast Pac jet won't let much turn the corner or phase

[psv88]

Truly horrrific

[jm1220]

8 minutes ago, psv88 said:

A shame Friday won’t work out. Cant believe mid Atlantic snows before us 

I can definitely believe it. Continuation of last winter’s crap. 

[WX-PA]

9 minutes ago, MJO812 said:

Phase 8 this week

Models are active. Just need to get it timed right. 

That works for December..Rather be in phase 8 than 4 or 5 which we have seen numerous Decembers.If this is true should be an exciting holiday season this year.

[Neblizzard]

7 minutes ago, Brian5671 said:

Same ol pattern.   Fast Pac jet won't let much turn the corner or phase

We may have to toss December 

[WX-PA]

2 minutes ago, Neblizzard said:

We may have to toss December 

Believe me it will be cold and very active. I think we get a few shots of winter precip this month.

[eduggs]

6z ECM has 0.10 to 0.15 liquid on Friday for our area. Not much support. The Canadian/GEPS shows a weak Norlun signature on Sat. morning. Weak overrunning can sometimes trigger precipitation much further north than anticipated... but virga is the likely result. 

[rclab]

52 minutes ago, BxEngine said:

Hes one of the kids that posts pessimistic shit this way when it inevitably happens, he can claim victory and also be mentally prepared for the sadness that people feel when they dont get what they actually want. And if we happen to get snow they wont acknowledge the incorrect posts, just move on and enjoy their snow they wanted while being doubly excited because they were pessimistic. Freud would have a field day in this forum.   

Possibly each of us with our own chapter? Stay calm and lucid ….. as always …
 

[North and West]

We may have to toss December 

On December 3?



.

[eduggs]

Unfortunate wave timing on the models right now. The southern stream shortwaves for Friday and Sunday are perfectly timed with a northern stream shortwave to suppress the flow out ahead of them and prevent amplification. On the GFS, the subsequent wave on Wednesday instead has a little ridging in the northern stream out ahead of it and easily amplifies into a cutter.

We should avoid simplistic black and white statements like the Pacific is somehow preventing snowstorms. For each of the next several waves, a subtle and random shift in the height field could or could have allowed snow for us. We've always had wave interference. It's why it doesn't snow every week in our region. This is our climo. When the pieces fit together, it will snow. Same as it's always been.

[EastonSN+]

5 minutes ago, eduggs said:

Unfortunate wave timing on the models right now. The southern stream shortwaves for Friday and Sunday are perfectly timed with a northern stream shortwave to suppress the flow out ahead of them and prevent amplification. On the GFS, the subsequent wave on Wednesday instead has a little ridging in the northern stream out ahead of it and easily amplifies into a cutter.

We should avoid simplistic black and white statements like the Pacific is somehow preventing snowstorms. For each of the next several waves, a subtle and random shift in the height field could or could have allowed snow for us. We've always had wave interference. It's why it doesn't snow every week in our region. This is our climo. When the pieces fit together, it will snow. Same as it's always been.

Great post!!

[MJO812]

30 minutes ago, Neblizzard said:

We may have to toss December 

Lol

[eduggs]

There could be flakes in the air on Thurs, Fri, and/or Sat from 3 different mechanisms. After the arctic front passes on Thurs, it should be cold enough everywhere. If the ground gets dusted white you will feel better about winter.

The Sat. shortwave probably will only trigger flurries, but it's well positioned with a weak offshore SLP to potentially initiate an inverted trof (norlun) especially for eastern areas/SNE.

[Krs4Lfe]

22 minutes ago, MJO812 said:

Lol

After missing out on snow on Friday, it looks like we'll have that warm/cutter mid month. So then we're looking at second half of month for any snow. However, the fast flow is not allowing for anything. At least it'll be cold

[NorthShoreWx]

2 hours ago, donsutherland1 said:

For Baltimore, the snowfall cases are far more mixed.

I think the Dec 1 - 10 mean and median calcs are off.  Eyeballing the list, they should be in the 3" range.

[donsutherland1]

38 minutes ago, NorthShoreWx said:

I think the Dec 1 - 10 mean and median calcs are off.  Eyeballing the list, they should be in the 3" range.

Thank you. It seems that the formula dropped "T" rather than counting it as 0 on the spreadsheet. Mean: 3.5"; median: 2.0"

[Dark Star]

3 hours ago, psv88 said:

A shame Friday won’t work out. Cant believe mid Atlantic snows before us 

It seems that's becoming more and more the norm...

[NorthShoreWx]

1 hour ago, donsutherland1 said:

Thank you. It seems that the formula dropped "T" rather than counting it as 0 on the spreadsheet. Mean: 3.5"; median: 2.0"

I have that problem with the excel files I maintain for my climate records.  For my monthly snowfall summary ( https://www.northshorewx.com/ClimateData/SmithtownDailySnowfall.pdf ) I have a 0 for months where there were traces so that the averages don't get messed up (excluding October and May where the average is 0). 

I keep sheets with the daily data including traces, but I can't calculate an average value for a given date (e.g., December 3) because of all the years that have a trace on that date.  As a result, the difference between the actual average seasonal snowfall and the sum of the daily averages for the season in excel is significant; 36.2" vs 41.0"