January 10-12, 2025 | NE / Mid-Atlantic Winter Storm

[Penn State]

The 2025 Pennsylvania Farm Show is scheduled for January 4th-11th.. an event that showcases the Keystone State’s leading agricultural industry. If you’ve never attended.. you should make the trip! Especially for a homemade PA Dairymen’s Association milkshake! If you’re from Pennsylvania.. You probably know what I’m going to reference next. PA Farm Show week is traditionally synonymous with snowstorms. Now, statistically, is it more likely to snow during farm show week? No.. but.. historically, it does snow about 40% of the time. The most notable farm show week snowstorm was the Blizzard of ‘96.. which occurred on January 6th-8th of the aforementioned year. As a matter of fact.. 🧐 one of the CPC’s 8-14 day analogs for early January is late December 1995.. about a week before the Blizzard of ‘96. So.. as we approach 2025.. the question is, can the PA Farm Show be a bellwether of wintry weather once more? 

Sure! But.. It’s complicated. The pattern is supportive of a high-impact event in the Mid-Atlantic and Northeast, but it’s far from a guarantee. The forecasted teleconnections are favorable, indicating both a -AO, -NAO, along with a +PNA. This configuration would signal an injection of cold air, combined with sufficient blocking and ridging to support a potential winter storm. The MJO indicates convection. Moving through the equatorial Pacific, consistent with phases 7 and 8.. which corresponds with an enhanced subtropical jet and the potential for storminess in the U.S. following a roughly 2 week delay from the 1st of January. In addition.. The Bering Sea Rule (BSR) is active during this timeframe. A storm is present near 160W, 50N on December 25th.. which would correspond to storminess 17-21 days later, during the later part of the 2nd week of January. 

Modeling has been consistent in showing the potential for a significant and impactful winter storm.. along with some of the coldest air of the season thus far. However, that potential has not consistently been depicted with each model run. The ECMWF and GFS have both provided hints, but ensembles have offered nothing definitive. At the very least.. this upcoming period (January 4th-18th) appears to be the best opportunity for a widespread and meaningful winter storm we’ve had in quite some time. Let’s see if we get some well-timed shortwaves to interact with the polar, pacific, and subtropical jets.. all with a favorable EPO, 50/50 low, and perfectly placed 500MB ridging over Montana.. Whew.. that sounds like a lot! 😩 But.. hey, it’s happened before, and it will again. 

So, setting the table for this thread.. it’s quite speculative.. one leaning on organic forecasting and loose ensemble, operational, and AI support. It’s also a thread that covers a wide blanket of dates, which will eventually be narrowed, but focus on January 10th. Over the next few days, the hope is that ensembles add clarity to chaos.. or.. at least continue to show potential! Anyways, let’s get after it! Included is the most recent 18z ECMWF AIFS.. which will serve as a discussion starter. Stay tuned for additional details! 

Merry Christmas, Happy Holidays, & Happy Tracking! 🤓

Model Guidance | 18z ECMWF AIFS (Hours 336-360) 

MSLP Surface Map

500 MB & Vorticity Map 

Ensemble Guidance | 12z EPS (Hour 360) 

500 MB Height Anomaly 

 

Spoiler

Operational Model Guidance | Surface & 500 MB Vorticity (Hours 312-384)

00z ECMWF 

00z GFS 

Ensemble Model Guidance | 500 MB Height Anomaly & MSLP Members (Hours 312-384)

00z EPS

00z GEFS 

Teleconnections 

MJO Forecast 

AO Forecast

NAO Forecast 

PNA Forecast 

North Pacific | Bering Sea Rule (BSR) 

Analogs | CPC 8-14 Day 

 

Edited January 9 by Penn State

[Penn State]

Mike Thomas.. Someone that I follow on “X”.. With some analog analysis. It’s something that I’ve been following on CIPS and the CPC. As Mike points out.. certainly not a guarantee that any particular potential will materialize, but.. it’s indicative of the pattern. With the right ingredients, an historic storm is at least plausible. We’re certainly due for one! 

[Undertakerson2.0]

I contemplated starting a thread for these dates yesterday - but I'm actually so Anti-Snow and Cold anymore I could not bring myself to do it.

The 00z Euro, with a Miller B that, pauses at the 40/70 benchmark - will surely get the discussion off to a rollicking start

 

 

 

Edited December 27, 2024 by Undertakerson2.0

[MaineJay]

Plenty o' bangers in there. Just 13 days to go.

[Wally Ho]

8 hours ago, Penn State said:

The 2025 Pennsylvania Farm Show is scheduled for January 4th-11th.. an event that showcases the Keystone State’s leading agricultural industry. If you’ve never attended.. you should make the trip! Especially for a homemade PA Dairymen’s Association milkshake! If you’re from Pennsylvania.. You probably know what I’m going to reference next. PA Farm Show week is traditionally synonymous with snowstorms. Now, statistically, is it more likely to snow during farm show week? No.. but.. historically, it does snow about 40% of the time. The most notable farm show week snowstorm was the Blizzard of ‘96.. which occurred on January 6th-8th of the aforementioned year. As a matter of fact.. 🧐 one of the CPC’s 8-14 day analogs for early January is late December 1995.. about a week before the Blizzard of ‘96. So.. as we approach 2025.. the question is, can the PA Farm Show be a bellwether of wintry weather once more? 

Sure! But.. It’s complicated. The pattern is supportive of a high-impact event in the Mid-Atlantic and Northeast, but it’s far from a guarantee. The forecasted teleconnections are favorable, indicating both a -AO, -NAO, along with a +PNA. This configuration would signal an injection of cold air, combined with sufficient blocking and ridging to support a potential winter storm. The MJO indicates convection. Moving through the equatorial Pacific, consistent with phases 7 and 8.. which corresponds with an enhanced subtropical jet and the potential for storminess in the U.S. following a roughly 2 week delay from the 1st of January. In addition.. The Bering Sea Rule (BSR) is active during this timeframe. A storm is present near 160W, 50N on December 25th.. which would correspond to storminess 17-21 days later, during the later part of the 2nd week of January. 

Modeling has been consistent in showing the potential for a significant and impactful winter storm.. along with some of the coldest air of the season thus far. However, that potential has not consistently been depicted with each model run. The ECMWF and GFS have both provided hints, but ensembles have offered nothing definitive. At the very least.. this upcoming period (January 4th-18th) appears to be the best opportunity for a widespread and meaningful winter storm we’ve had in quite some time. Let’s see if we get some well-timed shortwaves to interact with the polar, pacific, and subtropical jets.. all with a favorable EPO, 50/50 low, and perfectly placed 500MB ridging over Montana.. Whew.. that sounds like a lot! 😩 But.. hey, it’s happened before, and it will again. 

So, setting the table for this thread.. it’s quite speculative.. one leaning on organic forecasting and loose ensemble, operational, and AI support. It’s also a thread that covers a wide blanket of dates, which will eventually be narrowed, but focus on January 10th. Over the next few days, the hope is that ensembles add clarity to chaos.. or.. at least continue to show potential! Anyways, let’s get after it! Included is the most recent 18z ECMWF AIFS.. which will serve as a discussion starter. Stay tuned for additional details! 

Merry Christmas, Happy Holidays, & Happy Tracking! 🤓

Model Guidance | 18z ECMWF AIFS (Hours 336-360) 

MSLP Surface Map

500 MB & Vorticity Map 

Ensemble Guidance | 12z EPS (Hour 360) 

500 MB Height Anomaly 

 

  Reveal hidden contents

Operational Model Guidance | Surface & 500 MB Vorticity (Hours 312-384)

00z ECMWF 

00z GFS 

Ensemble Model Guidance | 500 MB Height Anomaly & MSLP Members (Hours 312-384)

00z EPS

00z GEFS 

Teleconnections 

MJO Forecast 

AO Forecast

NAO Forecast 

PNA Forecast 

North Pacific | Bering Sea Rule (BSR) 

Analogs | CPC 8-14 Day 

 

Very informative and thorough thread opener, Penn!  Great job!!!  It certainly appears as if the stage is set for that second week of January. 😳

[geeter1]

Looks like a lot of moisture for this time period...😎

[MaineJay]

Timing on these is gonna be difficult.  Might have to deal with a few false positives, and adjust dates. Even add a thread if necessary, but gonna leave the dates as is, just please reference the timeframe when discussing.  

 This thread covers 5 days, so be specific until we can narrow things down.

[Electric_CityWx]

14 hours ago, Penn State said:

You probably know what I’m going to reference next. PA Farm Show week is traditionally synonymous with snowstorms.

LMFAO That was exactly my first thought while reading PA Farm Show hahahahahaha!!!!!

[Undertakerson2.0]

19 minutes ago, Electric_CityWx said:

LMFAO That was exactly my first thought while reading PA Farm Show hahahahahaha!!!!!

It's a non traditional cause and effect situation. 

 

 

[Penn State]

24 minutes ago, Electric_CityWx said:

LMFAO That was exactly my first thought while reading PA Farm Show hahahahahaha!!!!!

It’s interesting.. when I was posting, I was like.. it’s easy to know about farm show week in PA because it’s tradition, but folks from outside the region probably don’t know much about it.

[Penn State]

4 minutes ago, Undertakerson2.0 said:

It's a non traditional cause and effect situation. 

 

 

I was interested in the 40% statistic.. That came from ABC 27 a few years ago. All coincidence though.. Farm Show just lands in a good place on the winter calendar.

[StretchCT]

[Rickrd]

I like this time frame looking at the pattern. 
also, should have plenty of cold hanging around. A specific storm is difficult to pinpoint   at this time unfortunately. 

[Penn State]

17 minutes ago, StretchCT said:

Clippers actually.. lol.. which, at the moment looks like a good call with the NW flow. Glad to see a Snobal reference make an appearance. Wish he (or she) would find his on here lol 

[Undertakerson2.0]

Felt I should cross post between as the CPC information spans both

[Penn State]

[Penn State]

Weather Twitter has been abuzz today.. Bernie Rayno making some posts, really the first I’ve seen him making noise this season. 

[Penn State]

So far.. at 00z.. I like what I see. Has that bowling ball look. It’ll probably get squashed or something, but initially, looks pretty. 

[Cdfarabaugh]

4 hours ago, Penn State said:

Weather Twitter has been abuzz today.. Bernie Rayno making some posts, really the first I’ve seen him making noise this season. 

I'm greedy.... I want both!  

[Undertakerson2.0]

9 hours ago, Penn State said:

Weather Twitter has been abuzz today.. Bernie Rayno making some posts, really the first I’ve seen him making noise this season. 

All disrespect intended here for "Accu - BURN" - that is a ridiculous statement to make

I particularly LOVE how the very next model suite both GFS and Euro Op disprove his statement "you WON'T get both".

Why would you say that? The Pac is and seems to want to be, a virtual breeding ground for shortwaves.

NYC got an inch of snow for Xmas for the first time since 2009. Those of you who still have sufficient brain cells left (unlike me) surely remember Snowmageddon that followed! 

I'd have been cool with him saying 'may not get both' or 'unlikely to get both' - but his statement reinforces why I can't stand this dude - he's like JB and Henry M level aggravating to me. 

[JDClapper]

26 minutes ago, Undertakerson2.0 said:

All disrespect intended here for "Accu - BURN" - that is a ridiculous statement to make

I particularly LOVE how the very next model suite both GFS and Euro Op disprove his statement "you WON'T get both".

Why would you say that? The Pac is and seems to want to be, a virtual breeding ground for shortwaves.

NYC got an inch of snow for Xmas for the first time since 2009. Those of you who still have sufficient brain cells left (unlike me) surely remember Snowmageddon that followed! 

I'd have been cool with him saying 'may not get both' or 'unlikely to get both' - but his statement reinforces why I can't stand this dude - he's like JB and Henry M level aggravating to me. 

I hear ya UTS! We arent even fully within hr 240 for the first possible event and making that statement "of fact"?  Maybe he is referring to "major" impacts or something, but now I am trying to insert context where there is none.

Anywho, I will take back to back bookers if thats what the weather wants to provide. And if it is just one, okie doke, let's go!

[BuckeyeGal]

3 hours ago, Undertakerson2.0 said:

All disrespect intended here for "Accu - BURN" - that is a ridiculous statement to make

I particularly LOVE how the very next model suite both GFS and Euro Op disprove his statement "you WON'T get both".

Why would you say that? The Pac is and seems to want to be, a virtual breeding ground for shortwaves.

NYC got an inch of snow for Xmas for the first time since 2009. Those of you who still have sufficient brain cells left (unlike me) surely remember Snowmageddon that followed! 

I'd have been cool with him saying 'may not get both' or 'unlikely to get both' - but his statement reinforces why I can't stand this dude - he's like JB and Henry M level aggravating to me. 

Very ballsy of him, for sure. And strange.. considering most mets leave 'an out' exactly like you said. 

[Penn State]

This morning he’s calling it “double trouble” with an explanation.. Sort of saying the 2nd one is dependent on the 1st, which makes sense. Certainly though.. think we can get both, no absolutes this far out. 

The other thing that this thread may cover.. if not for a storm.. that’s some impressive cold shown on the Euro last night. Wow. 😮 In the image below.. that’s 1PM on January 11th and the entire state of PA is below zero. 

[Penn State]

Also this.. from someone I think people generally like lol.. Cranky, er.. Content?

It goes to.. a lot of ingredients are in the kitchen, and we’re all hungry, it’s frustrating when it won’t cook. 

Edited December 28, 2024 by Penn State

[Jon Snow]

1 hour ago, Penn State said:

This morning he’s calling it “double trouble” with an explanation.. Sort of saying the 2nd one is dependent on the 1st, which makes sense. Certainly though.. think we can get both, no absolutes this far out. 

The other thing that this thread may cover.. if not for a storm.. that’s some impressive cold shown on the Euro last night. Wow. 😮 In the image below.. that’s 1PM on January 11th and the entire state of PA is below zero. 

Even if that is off by as much as 50%, that would be brutal.  Lets just hope it is not off by 50% in the cold direction