December Medium/ Long Range

[Terpeast]

For Dec 3-7, GEPS still shows a signal for a coastal with plenty of cold, and EPS to a lesser extent. GEFS not picking anything up yet. 

Haven’t bought in for the Thanksgiving storm. I’m almost certain it will be rain for just about everyone except interior NE. Not cold enough yet. 

[Eskimo Joe]

6 hours ago, WxUSAF said:

All 3 ensembles keep the PNA/EPO/WPO ridging going strong at D15. Cross polar flow the whole time. 

If it's one thing I've learned over the past decade, it's that you really need the Pacific on your side to have a shot. Otherwise it's all about pinpoint timing.

1 hour ago, NorthArlington101 said:

06z AI Euro shows the path to a successful Thurs/Friday. Surface is still too warm, but with the 850s I imagine this is snow. Pretty identical to its 00z run too. Slightly better timing allowing accumulations to start overnight could = success

-3 to -5 will get you TV Snow at least west of I-95.

[stormy]

1 hour ago, NorthArlington101 said:

I’ll wait for my AI darling to let us down before I let the fat lady sing. Spire also has a storm… AI revolution?

Yeah, the 06z  A1 does look interesting!  I hadn't looked at it today.  A little beef up in stead of back down.  Surface is marginal in mid 30's but 850's look good at minus 4!  When will the 12z be available? 

[yoda]

1 hour ago, ORH_wxman said:

Prob need to start a December thread but EPS not backing down on the PAC pattern. Really consistent with holding that ridge axis right over the west coast

 

 

EPS continues to look good... I just hope it is this way next week on the models

[CAPE]

11 minutes ago, yoda said:

EPS continues to look good... I just hope it is this way next week on the models

Hard to complain and looks cold, but remains to be seen how conducive it is for getting a significant NS shortwave to dig enough to develop a storm south of our latitude. Probably need an anticyclonic wave break to get 

a shortwave embedded in the flow to dive further southward/further west than these panels imply.

[NorthArlington101]

12Z EURO AIFS stays consistent with a pretty ideal track. It's just iffy surface temps. 850s tighter this go around too.

Regardless of whether this threat has any legs, interesting test of whether the AIFS might be sniffing something out

[Ji]

4 minutes ago, NorthArlington101 said:

12Z EURO AIFS stays consistent with it's pretty ideal track. It's just iffy surface temps. 850s tighter this go around too.

Regardless of whether this threat has any legs, interesting test of whether the AIFS might be sniffing something out

seems like the operational models are focused more on Thursday than anything on friday. Putting all their eggs into the front runner

[NorthArlington101]

1 hour ago, Ji said:

seems like the operational models are focused more on Thursday than anything on friday. Putting all their eggs into the front runner

18z GFS is gonna be a day earlier than the AIFS again it looks like. Difference is very clear at ~3 days on the GFS. Again, this is mostly an exercise in my head to reference later to see if the AI is gonna do anything for us this winter, but GFS pushes the energy onshore at like hr66. It gets held back and weakened on the AIFS which lets more cold build in/suppresses things south in the long run. Note the time differences below.

[WEATHER53]

Ma*t

The effects of cold Mongolian high pressure that I mentioned would be 8-10  days away earlier this week will arrive Friday night thru Sunday next werk  with Sat  and Sunday daytime highs in -15 departure range, highs around 40.

its a good first shot  start 

[Eskimo Joe]

48 minutes ago, NorthArlington101 said:

18z GFS is gonna be a day earlier than the AIFS again it looks like. Difference is very clear at ~3 days on the GFS. Again, this is mostly an exercise in my head to reference later to see if the AI is gonna do anything for us this winter, but GFS pushes the energy onshore at like hr66. It gets held back and weakened on the AIFS which lets more cold build in/suppresses things south in the long run. Note the time differences below.

I hope this isn't a sign of this becoming a west coast trough that just dumps cold out west and we wind up with a raging southeast ridge.

[North Balti Zen]

8 minutes ago, Eskimo Joe said:

I hope this isn't a sign of this becoming a west coast trough that just dumps cold out west and we wind up with a raging southeast ridge.

I mean…that would be a repeat of a pattern that we’ve seen for years now. It is certainly believable.

[Prestige Worldwide]

Dare I say Siberian cold air headed our way?

[Eskimo Joe]

 

 

[Benjamn3]

Early Dec looks great, I just hope the pattern stays for the month or leaves and pumps back for the holidays.

[WxUSAF]

4 minutes ago, Eskimo Joe said:

 

 

If it was January or February, we’d be looking at 10s for highs and lows near 0 probably, even without snowcover. I’ll be quite impressed if we get a sub-freezing high out of the first week of December. Very impressed if DCA manages that, but I’d bet against it. 

[winter_warlock]

39 minutes ago, WxUSAF said:

If it was January or February, we’d be looking at 10s for highs and lows near 0 probably, even without snowcover. I’ll be quite impressed if we get a sub-freezing high out of the first week of December. Very impressed if DCA manages that, but I’d bet against it. 

 I think it will be the coldest  airmass in December  alot of us have seen in  about a decade. 

[midatlanticweather]

4 hours ago, NorthArlington101 said:

12Z EURO AIFS stays consistent with a pretty ideal track. It's just iffy surface temps. 850s tighter this go around too.

Regardless of whether this threat has any legs, interesting test of whether the AIFS might be sniffing something out

I think it may be sniffing glue 

 

[NorthArlington101]

I think it may be sniffing glue 
 

Didn’t cave at 18z, but still too warm at the surface!

[CAPE]

1 hour ago, Eskimo Joe said:

 

 

Anomalous early season winter cold with no moisture. Woot!

[winter_warlock]

4 hours ago, NorthArlington101 said:

12Z EURO AIFS stays consistent with a pretty ideal track. It's just iffy surface temps. 850s tighter this go around too.

Regardless of whether this threat has any legs, interesting test of whether the AIFS might be sniffing something out

How accurate is the 12Z EURO AIFS compared to the typical EURO? just curious 

[Maestrobjwa]

9 minutes ago, CAPE said:

Anomalous early season winter cold with no moisture. Woot!

My bar is so low that I'm almost okay with it just being cold in December for a change! Besides how often do we do anomalous cold with snow?

[Eskimo Joe]

1 hour ago, WxUSAF said:

If it was January or February, we’d be looking at 10s for highs and lows near 0 probably, even without snowcover. I’ll be quite impressed if we get a sub-freezing high out of the first week of December. Very impressed if DCA manages that, but I’d bet against it. 

I'd just be happy with climo at this point. For me, I'm hoping this doesn't turn out to be a last minute rug pull like last year.

[NorthArlington101]

How accurate is the 12Z EURO AIFS compared to the typical EURO? just curious 

Supposedly better in some ways, worse in others (worse resolution). They have a write up on their site:

https://www.ecmwf.int/en/newsletter/178/news/aifs-new-ecmwf-forecasting-system

Either way, should in theory have some utility. It’s not a waste to look. It is firmly on an island right now, though.

[Deck Pic]

4 hours ago, WEATHER53 said:

Ma*t

The effects of cold Mongolian high pressure that I mentioned would be 8-10  days away earlier this week will arrive Friday night thru Sunday next werk  with Sat  and Sunday daytime highs in -15 departure range, highs around 40.

its a good first shot  start 

we are a cold town

[Ji]

we are a cold town

I’m too old for cold and dry

[NorthArlington101]

I’m too old for cold and dry

I walk or bike to work. I’m now mostly in the camp of “if it’s not gonna snow it might as well be 70.” Cold blows.

[Round Hill WX]

2 hours ago, WxUSAF said:

If it was January or February, we’d be looking at 10s for highs and lows near 0 probably, even without snowcover. I’ll be quite impressed if we get a sub-freezing high out of the first week of December. Very impressed if DCA manages that, but I’d bet against it. 

With record warm Great Lake temps and this type of cold, there is gonna be some epic lake effect snows. May be some good chasing opportunities. 

[Weather Will]

I will try to find you folks a 10% snow prob. Map at 0Z.

Cone on everyone, we need cold first.  The fact that it can still even get cold is a start.  Actually cold and dry is a long time phenomenon here... the way it was for most of the 70s before global warming was a thing.

[Weather Will]

WB 18Z EURO.  We need the rain.  Be thankful.

[NorthArlington101]

I don’t think it’s gonna be meaningful in either case but 00z GFS and CMC seem to be making meaningful moves towards a more AI Euro-like evolution.