January 2026 Medium/Long Range Discussion

[GreyHat]

Currently NWS forecast for this storm for Magnolia Delaware 

Saturday

A chance of snow. Partly sunny, with a high near 23. Chance of precipitation is 30%.

Saturday Night

A chance of snow. Mostly cloudy, with a low around 9. Chance of precipitation is 30%.

Sunday

A chance of snow. Partly sunny, with a high near 21. Chance of precipitation is 40%.

[Ji]

Stolen from the southern forum. Just out to 144, of course

Uuuugh

[mitchnick]

3 minutes ago, Maestrobjwa said:

Stolen from the southern forum. Just out to 144, of course

I know, that's why I posted. It shifted south.

[Ephesians2]

37 minutes ago, GreyHat said:

Would a stronger L like 991 push noth?

Disclaimer: I'm not the expert at upper level analysis by any means

[Edited to remove a sentence that demonstrated that fact]

But this doesn't look quite like the "HECS" look that supports a low that strong though its a very good pattern

This is -EPO, -NAO, with a neutral looking PNA with the ridge offshore. The -EPO delivers arctic air while the -NAO stops the storm from cutting NW. 

This looks like it would support, at the upper potential, an overrunning event like Jan 2010 or... Dec 2018 (you all would love that if it had been 100 miles north) with widespread double digits totals, but not the 18-24"+ totals that would be "historic". 

[GreyHat]

2 minutes ago, Ephesians2 said:

Disclaimer: I'm not the expert at upper level analysis by any means

But this doesn't look quite like the "HECS" look that supports a low that strong though its a very good pattern

This is -EPO, -NAO, with a neutral looking PNA with the ridge offshore. The -EPO delivers arctic air while the -NAO stops the storm from cutting NW. But for a truly historic storm it would seem like we'd need the ridge a few hundred miles east which would push the trough southeast over the TN valley and phase with the subtropical energy and create a stronger storm. 

This looks like it would support, at the upper potential, an overrunning event like Jan 2010 or... Dec 2018 (you all would love that if it had been 100 miles north) with widespread double digits totals, but not the 18-24"+ totals that would be "historic". 

Thanks, here to observe and learn, the days of doorman, PSU and others from the different forms was always a great reading.

[Maestrobjwa]

4 minutes ago, mitchnick said:

I know, that's why I posted. It shifted south.

Oh my bad I was looking at the gifs in the wrong order, lol Darn it

[bncho]

1 minute ago, GreyHat said:

Thanks, here to observe and learn, the days of doorman, PSU and others from the different forms was always a great reading.

Well IMO he's partially right, the -NAO obviously helps but it's mainly because a 1050 high squashes everything

 

[NorthArlington101]

one step closer to purple than we usually get 

[aldie 22]

12 minutes ago, Maestrobjwa said:

Stolen from the southern forum. Just out to 144, of course

Hey at least we have AL's models on our side

[Maestrobjwa]

3 minutes ago, aldie 22 said:

Hey at least we have AL's models on our side

Yeah I'm having a hard time believing those, tbh. Until we see less suppression from the regulars it'll be hard to buy it

[Terpeast]

Just woke up. I’ll summarize… models basically held. We’re on the northern part of the precip shield, which could help our ratios and h700 fgen forcing. Cold high is starting to weaken (was probably overdone).

And I’ll address this:

9 minutes ago, Ephesians2 said:

Disclaimer: I'm not the expert at upper level analysis by any means

But this doesn't look quite like the "HECS" look that supports a low that strong though its a very good pattern

This is -EPO, -NAO, with a neutral looking PNA with the ridge offshore. The -EPO delivers arctic air while the -NAO stops the storm from cutting NW. But for a truly historic storm it would seem like we'd need the ridge a few hundred miles east which would push the trough southeast over the TN valley and phase with the subtropical energy and create a stronger storm. 

This looks like it would support, at the upper potential, an overrunning event like Jan 2010 or... Dec 2018 (you all would love that if it had been 100 miles north) with widespread double digits totals, but not the 18-24"+ totals that would be "historic". 

in this specific case, move that pna ridge a few hundred miles east, and we’ll suppress this thing all the way to the gulf. The EPO is so strong that we need a little SE ridging to give us a good overrunning event. It’s not the same thing as a bomb cyclone HECS, but overrunning with lots of cold can produce a lot of snow if strong enough. 

[SnowenOutThere]

KEY MESSAGE 2...The potential for a possibly significant winter
storm has increased for this weekend, but uncertainty remains.

The upper air pattern resembles what appears to be a very
favorable pattern for a winter storm somewhere in the eastern
U.S. heading into this weekend. Before that, a potent cold
front pushes through the region late Thursday into Friday,
followed by a reinforcing Arctic front late Friday into
Saturday. This will lead to increasingly cold conditions each
day from Thursday through the entire weekend. Well below average
temperatures are forecast, especially by Sunday. In addition,
some upslope snow showers are possible with each front.

By the end of the week and especially heading into the weekend,
the upper-level pattern becomes quite active in both the
northern and southern branches of the jet stream. Model guidance
is still very much all over the place in regards to exactly
what comes of this, but there is growing consensus for an area
of low pressure developing across the south-central/southeastern
CONUS. Depending on when and where that area of low pressure
develops, as well as where it goes after it does develop, there
could be significant wintry precipitation across our area
sometime next weekend. Uncertainty remains with this system, as
there is some potential that strong Arctic high pressure could
suppress the system south. However, that high (~1040 mb Arctic
high) is also a source of very cold air; this likely remains in
place due to a favorable -AO/-NAO blocking pattern. Meanwhile,
there are an increasing amount of ensemble members that bring
significant wintry precipitation to the region due to an
amplified southern stream influence - something we have seen
very little of so far this winter (typical of La Nina). The low
may not escape as easily out to sea given the -NAO block. The
nearby steady source of very cold air and the amplified southern
stream occurring in tandem are what raise some red flags for
significant wintry precipitation potential this weekend.

The latest ensemble guidance is certainly on the upward trend
in that regard, but that doesn`t mean it can`t swing back in the
other direction. It will be key to monitor this threat closely
in the coming days as the different parts of the system become
better sampled by surface and upper air obs. Current model
spread indicates an axis of significant snow/ice could be as
far north as Upstate New York, or as far south as the Carolinas.

Bolded some key parts of the afd  

[aldie 22]

14 minutes ago, Ji said:

Uuuugh

You're going to have a long week....If i were you i would be very vague in your FB posts and really vague for your paying customers lol

[SnowenOutThere]

1 minute ago, Terpeast said:

Just woke up. I’ll summarize… models basically held. We’re on the northern part of the precip shield, which could help our ratios and h700 fgen forcing. Cold high is starting to weaken (was probably overdone).

And I’ll address this:

in this specific case, move that pna ridge a few hundred miles east, and we’ll suppress this thing all the way to the gulf. The EPO is so strong that we need a little SE ridging to give us a good overrunning event. It’s not the same thing as a bomb cyclone HECS, but overrunning with lots of cold can produce a lot of snow if strong enough. 

My thinking is similar to yours. Personally I think we’re in a pretty good spot as of now considering that the AI GFS/Ukmet are almost too far north. Main thing I want to see out of today is the Euro and Euro ai to hold and have the CMC and GFS come closer to that solution. I think the way we get that is have the pv to our northeast be a bit less intense or (better yet though less likely) have a stronger low. That said, I wouldn’t want models to all suddenly jump way north today but just show increasing confidence a total miss to the south is unlikely.  

[mitchnick]

5 minutes ago, aldie 22 said:

You're going to have a long week....If i were you i would be very vague in your FB posts and really vague for your paying customers lol

He better, or he'll have to give his wife and kids back their money.

[bncho]

FWIW, the Euro AI was almost dead on at D5. It took the Euro longer to get there for yesterday's event.

Tonight's runs will be 5 days out. If the Euro AI continues to show similar solutions I see very little reason why not to believe it.

[WxUSAF]

4 minutes ago, bncho said:

FWIW, the Euro AI was almost dead on at D5. It took the Euro longer to get there for yesterday's event.

Tonight's runs will be 5 days out. If the Euro AI continues to show similar solutions I see very little reason why not to believe it.

The one caveat, which is hard to evaluate, is whether the high pressure (and associated upper level configuration) will be so anomalous, that the AI will, by its nature, not predict it.  The AI models are trained on some amount of reanalysis, and so they can't/won't predict extreme or record-breaking events well.  Will this setup be record-breaking?  Hard to say.  But that's something to keep in mind when evaluating the AI models vs the physics-based models.  

[aldie 22]

3 minutes ago, WxUSAF said:

The one caveat, which is hard to evaluate, is whether the high pressure (and associated upper level configuration) will be so anomalous, that the AI will, by its nature, not predict it.  The AI models are trained on some amount of reanalysis, and so they can't/won't predict extreme or record-breaking events well.  Will this setup be record-breaking?  Hard to say.  But that's something to keep in mind when evaluating the AI models vs the physics-based models.  

I desperately want to hang my hat on the fact that extreme record-breaking events are just that. We will know soon enough i suppose

[Eskimo Joe]

Phase 8

Neg AO

Neg NAO

Positive PNA

[Conway7305]

Can anyone post the Euro AI Ensembles?  

[Maestrobjwa]

5 minutes ago, Eskimo Joe said:

Phase 8

Neg AO

Neg NAO

Positive PNA

You'd think! A fail would just be bad luck i.e. a random anomalous high at the wrong time. But hopefully not!

[Eskimo Joe]

Thursday looks like the only "warm" day and that's upper 30s/low 40s. The rest of the week looks primed to keep the ground cold. High in the 30s, lows in the mid 20s. 

[bncho]

There are two possible outcomes for this event:
1. A major ice storm affects southern CAD zones, and DC and points north get a major snowstorm. (Euro AI, UKMET, GFS AI, Euro)
2. A major snowstorm affects southern CAD zones, and DC and points north receive little to nothing. (GFS, CMC)

What do we know of each model?
The Euro AI is often locked onto an event inside D5 and is often deadly inside that range, but can be locked onto an incorrect solution, only to fold 48 hours before the event (credit to @high risk). It also often has a QPF bias. 
The Euro often tends to overamp low pressure systems, but it also tends to hold back energy in the Baja. It also often has a QPF bias.
The GFS tends to show more suppressive, progressive solutions, and often tends to verify NW.
The CMC has a major cold bias, and tends to overdo Arctic HPs. It also, generally, has a suppressive bias, but it is less prominent than the GFS.
The UKMET tends to struggle on thermals, often being too warm. It also tends to overamp systems.
Since the GFS AI is new, I don't know much about it.

Although more operational models (that I'm aware of; I have no idea what Google's model outputs) support the northern solution, ensembles have been trending colder and snowier towards the southern solution over the last 24-36 hours. This is why I am skeptical to declare victory for the northern solution just yet.

It would be easy to go with the Euro AI, just because that has been the best performing operational this winter inside D5. However, a major caveat to this is that the upcoming HP may be so anomalous that it hasn't received enough training data to output the correct solution, just due to its inexperience (credit to @WxUSAF). This should be a good test for the AI Euro.

Now, it's too early to declare anything, but I am leaning towards the northern solution. 1050 HPs are extremely rare and often overdone in setups like these (credit @Terpeast), and I don't think it'll be able to suppress it enough. However, if a ultra-strong HP does pan out, the Euro AI may have a greater probability of being wrong.

Stay tuned...

[mitchnick]

6 minutes ago, Conway7305 said:

Can anyone post the Euro AI Ensembles?  

I don't have snowfall maps, but here is the total qpf for the event.

[mitchnick]

Just now, mitchnick said:

I don't have snowfall maps, but here is the total qpf for the event.

Closeup

[bncho]

8 minutes ago, Conway7305 said:

Can anyone post the Euro AI Ensembles?  

I'm too young to be looking at porn... 

[CAPE]

The 0z and 6z Euro Ens essentially look the same wrt precip/snowfall at 6z on Sunday, outside of run to run noise. There is no 'trend'. I am going to trust the Euro more overall for this potential event given how crappy the GFS has performed recently. I will lump the AI models in with the GFS/GEFS based on their performance with our recent (mostly Non) event.

[Terpeast]

1 minute ago, CAPE said:

The 0z and 6z Euro Ens essentially look the same wrt precip/snowfall at 6z on Sunday, outside of run to run noise. There is no 'trend' I am going to trust the Euro move overall for this potential event given how crappy the GFS has performed recently. I will lump the AI models in with the GFS/GEFS based on their performance with our recent (mostly Non) event.

The MSL pressure field actually shifted north in the TVA on 6z vs 0z eps. Mostly noise, but the shift was noticeable. 

[NorthArlington101]

FWIW - the new Canadian (I think it replaces the old in the spring) is light snow -> sleet -> little bit of FRZA. So it’s amped and totally different than the about-to-be-replaced version

[EastCoast NPZ]

I am going to look at the last 10 years of results and congratulate the fine people of VA Beach on another snow storm.

Weenie me.