November 2022

[sambucol]

From Larry Cosgrove posted at 6:50pm CST 11/26/22

Overview

James Bay Vortex, check. Strong dual blocking ridge in the Arctic Circle, check. Active southern branch storm track, check.

The ingredients for a wintry period of weather are all present for a long period of cold air and frozen precipitation potential across the lower 48 states. As stated before, the start of December will be relatively mild outside of the Pacific Northwest and the Prairie Provinces. But the immense, widespread chill in those regions is symptomatic of how conditions will evolve across the lower 48 states starting in about a week or so. The only protection against an Arctic invasion, so to speak, is the development of a subtropical high over the Greater Antilles and Strait of Yucatan. This heat ridge formation was overdone by the numerical model groups when the last big cold shot struck. Given that the positive 500MB height anomalies over Greenland, Northern Canada, and the Gulf of Alaska are so strong and well-situated, storm energy will consolidate into a cAk vortex over or near James Bay. That feature is classic in winter synoptic climatology, associated with widespread bitter cold, most especially in the Midwest, Great Lakes and Northeast. Think back to the winters of 1993-94 and 2013-14 for examples.

Now if for some reason the ECMWF panels are right with a summer-like heat ridge over the Gulf of Mexico, the cold would not get any further than an Interstate 40 line (Albuquerque NM to Wilmington NC). But that broad area of snow cover, the deepest in many years and about to get a lot deeper, will be an air mass refrigerant. Cold air is heavier and denser than the tropical regime, and if a storm comes along between the two late next week, the ridge complex will be crushed. I know that the various computer schemes have been erratic as of late. But when all of the numerical models show that familiar high-latitude warmth in the upper atmosphere, the most recent cold projections of the GFS and GGEM series, with the cold working down to the Gulf Coast, should verify in the December 7 - 21 period.

BOTTOM LINE

I also suspect that a widespread, and potent, ice and snow event will occur in the 11-15 day period. Track and coverage scenarios at this distance, of course, would be hard to define, though I am leaning toward a Colorado/Trinidad path of some sort with a wide variety of precipitation types from the Rocky Mountains into the Mid-Atlantic and New England states. As that system interacts with the likely presence of the aforementioned James Bay vortex, the cold numbers you see now in far northern Canada will be displaced. California and Florida should avoid the cold regime. But areas of North America to the right of the Rocky Mountains will be re-acquainted with the need for heating, heavy clothes, boots and hot chocolate.

[MontgomeryCoWx]

snowman65 no its not lmao

He does the same **** posting every winter regardless of what may be on the horizon. Not worth your time.

Crappy season for the Ags but tonight was fun. Geaux to hell LSU!

[Stratton20]

MontgomeryCoWxI was at the game! Perfect weather and just a great atmosphere all around

[sambucol]

Interesting Pow Ponder video https://youtu.be/ttjwkI_ZeXs

[Cpv17]

MontgomeryCoWxI was at the game! Perfect weather and just a great atmosphere all around

They need to buyout Jimbos contract. Plenty of rich millionaires/billionaires of alumni/boosters could get together and do it.

Meanwhile in the weather department, I feel like the models are going to be really inconsistent in the coming days. Could see a lot of wild swings.

[Stratton20]

Cpv17 I fully agree with you’re first statement, im sick of Jimbo, things are starting to line up for the first 2 weeks of december, could be very cold, the trend today has been for the SE ridge being weaker, GFS and the Euro start to break it down, and that should lead to the arctic air eventually being able to plunge south, also some really impressive blocking is showing up on some ensembles , interesting days ahead

[Cpv17]

Cpv17 I fully agree with you’re first statement, im sick of Jimbo, things are starting to line up for the first 2 weeks of december, could be very cold, the trend today has been for the SE ridge being weaker, GFS and the Euro start to break it down, and that should lead to the arctic air eventually being able to plunge south, also some really impressive blocking is showing up on some ensembles , interesting days ahead

Just going to depend on the placement of the strongest ridging imo.

[Iceresistance]

I have made a special nickname to the SE Ridge that only applies in the Winter

"The Anti-Winter Cockroach Ridge"!

[Cpv17]

Looking like a torch the first week of December.

[MontgomeryCoWx]

Looking like a torch the first week of December.

Short lived, but pretty typical during a Nina when big cold fronts are on the horizon.

It is becoming more frequent that we warm up into the 70s/80s before a plunge in temps.

[Stratton20]

Models are beginning to break down the SE Ridge faster, arctic air has been getting a little further south on the past few GFS, first week of december looks above average here, but my money is on a very cold december for Texas after that first week

[jasons2k]

Models are beginning to break down the SE Ridge faster, arctic air has been getting a little further south on the past few GFS, first week of december looks above average here, but my money is on a very cold december for Texas after that first week

Another winter season, another season of noise from the GFS breaking down the ridge too early. I’d put my money on that for awhile.

[Stratton20]

Jasons2k its not just one model, the euro is too, that warm up will be very brief
Even the latest EPS guidance has trended colder than normal after the first week of december, you warm weather lovers better enjoy the next few weeks, because it wont be around for too too long

[Cpv17]

The cold signal is definitely there on the ensembles past 9–10 days but it’s not really that strong of one. The -NAO is going absolutely bananas.

[DoctorMu]

We've been getting a lot of overrun and rain for a La Nina "winter." Each one is different.

Rain here was light and about 1.25 inches. That was just fine. Everything is watered or soaked well enough.

[Iceresistance]

I finished with 1.4 inches of rain

DFW is now above normal for 2022 rainfall, isn't that wild?

[tireman4]

I am thinking December will be a roller coaster ride.

[Cpv17]

I don’t really like what I see in the models to get the cold down this far south. I think it’ll stay up north but the dam will likely break at some point. Just a guessing game as to when. The -NAO alone is not enough to get the cold down here.

[Stratton20]

Cpv17 looking at the PNA, its current negative right now but its forecast to get closer to neutral in about 2-3 weeks, that is one thing that could work in favor for us, but until we get blocking to set up in the right position and this pesky SE Ridge to break down, we aren’t getting cold any time soon

[redneckweather]

Here we go...same thing every winter season. Most of the cold will go east and maybe once or twice we get a good glancing blow. There is nothing out of the ordinary that will be coming down over the next month or so but we are all weather lovers so it's fun to look at.