Bingo!
See 2002 December ice storm! Then winter was over
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Wintry Winter 2024-25 Discussion
- Thread starter SD
- Start date
See 2002 December ice storm! Then winter was over
Avalanche
Member
Yes, I like the idea of getting it over now with the holidays. January can warm up since we will all be ready for spring by then
iGRXY
Member
Who is we ?? lol
Brick Tamland
Member
December Dud? More like Dynamite December.
Brent
Member
Don't jinx it. December still 10 days away
lexxnchloe
Member
Going to the store to get my emergency supplies ready.
What??? After the December 2002 Ice Storm, there were 3 more good storms in January and February 2003
Only my absolute favorite snowstorm of all time
Webberweather53
Meteorologist
Updated this analog list to include things like Indian Ocean & Maritime Continent warmth, initialize w/ a +TNH in Dec (because when this happens oftentimes that TNH pattern persists throughout the winter), stronger than average zonal winds at 10mb in Dec, tweaked the weights, etc. I got a slightly different flavor to things, but the overall picture is generally the same as before, just amplified a bit more.
Here's how the gigantic (list of 350 years in total w/ weights) SST composite compares to observations in Oct-Nov. Of course only the first 25-30 or so are in the title, but there are a lot more in the background.
Here's the DJF 500mb mean pattern & 2m temp anomalies.
Interestingly, both this suite of analogs & the older set I came up with back in October sniffed out a cold December w/ a -EPO/+TNH. This new set is more amplified, in part because I explicitly looked for it this time, because a +TNH is likely going to happen.
Older analog set Dec 500mb pattern
Newer analog set Dec 500mb pattern.
Webberweather53
Meteorologist
I found it very interesting that these same 2 subsets of years, with the complete opposite mid-late winter temperature patterns over the CONUS, were all viable analogs for this upcoming winter!
When I took a closer look at the difference between these 2 subsets of years, I didn't notice anything out of the ordinary until I looked into the stratosphere.
The group w/ a colder Jan-Feb had a much cooler/stronger stratospheric polar vortex all the way up to 10mb. This allows the troposphere Hudson Bay Vortex to couple w/ and become "rooted" into the stratosphere, making it stronger/more persistent.
This seems to be one of the keys to getting this -EPO/+TNH pattern to "stick" into mid-late winter.
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Webberweather53
Meteorologist
When you compare -EPO and +EPO winters w/ cool neutral or La Niña ENSO like this year, some interesting things emerge.
EPO pattern difference
One of the things that really sticks out to me is the tendency for cool neutral - Nina years w/ -EPO to also be accompanied by a westerly QBO.
Piggy-backing off the previous post from a large-scale/dynamical point of view:
I suspect these cool ENSO winters w/ westerly QBO reduce upward/poleward wave activity onto the stratosphere polar vortex. This allows it to cool/spin-up over the Arctic & more specifically, Canada. If you can get a sufficient "trigger" to kickstart a -EPO/+TNH pattern in late fall or early winter, this pattern can effectively reinforce itself on longer time scales through positive feedbacks like wave driving & wave reflection, becoming increasingly more dominant as the winter wears on.
If you can further couple this stratospheric polar vortex w/ the Hudson Bay vortex in the troposphere, then you have the right recipe for potentially a very long-lived (& favorable) winter pattern.
Here are the 50mb zonal wind differences between -EPO & +EPO -ENSO years since the 1940s in ERA-5 & JRA-3Q:
This year is much more like the -EPO group of -ENSO winters, w/ a strong westerly QBO ~50mb.
EPO pattern difference
One of the things that really sticks out to me is the tendency for cool neutral - Nina years w/ -EPO to also be accompanied by a westerly QBO.
Piggy-backing off the previous post from a large-scale/dynamical point of view:
I suspect these cool ENSO winters w/ westerly QBO reduce upward/poleward wave activity onto the stratosphere polar vortex. This allows it to cool/spin-up over the Arctic & more specifically, Canada. If you can get a sufficient "trigger" to kickstart a -EPO/+TNH pattern in late fall or early winter, this pattern can effectively reinforce itself on longer time scales through positive feedbacks like wave driving & wave reflection, becoming increasingly more dominant as the winter wears on.
If you can further couple this stratospheric polar vortex w/ the Hudson Bay vortex in the troposphere, then you have the right recipe for potentially a very long-lived (& favorable) winter pattern.
Here are the 50mb zonal wind differences between -EPO & +EPO -ENSO years since the 1940s in ERA-5 & JRA-3Q:
This year is much more like the -EPO group of -ENSO winters, w/ a strong westerly QBO ~50mb.
Webberweather53
Meteorologist
This year so far is checking most of the boxes for the colder mid-late winter group w/ a westerly QBO & stronger early winter stratospheric polar vortex that would be more capable of coupling w/ the troposphere later on.
In fact, the polar vortex is forecast to be record strong at 10mb through at least mid-December on the extended GEFS & European weeklies.
In fact, the polar vortex is forecast to be record strong at 10mb through at least mid-December on the extended GEFS & European weeklies.
lexxnchloe
Member
From LC
However, when you look at the rebuild of the vast ridge complex along the entirety of the West Coast (AK and southward across Baja California), combined with renewed moderate -NAO ridging below Iceland), the CFS scenario of a new James Bay vortex suggests a cold December 23 - January 8 period to the right of the Rocky Mountains and above the Gulf Coast. If it sounds like late 1995, you would be right. This being a La Nina with a still-warm Gulf of Mexico, I lean toward a sudden January Thaw in the second week of the New Year. But a difference may be that as the 500MB features start going into their "peak of the season" positions, I lean toward more widespread cold with snow and ice possibilities to the right of the High Plains after mid-January.
However, when you look at the rebuild of the vast ridge complex along the entirety of the West Coast (AK and southward across Baja California), combined with renewed moderate -NAO ridging below Iceland), the CFS scenario of a new James Bay vortex suggests a cold December 23 - January 8 period to the right of the Rocky Mountains and above the Gulf Coast. If it sounds like late 1995, you would be right. This being a La Nina with a still-warm Gulf of Mexico, I lean toward a sudden January Thaw in the second week of the New Year. But a difference may be that as the 500MB features start going into their "peak of the season" positions, I lean toward more widespread cold with snow and ice possibilities to the right of the High Plains after mid-January.
Brent
Member
Whatever happens this winter no more snow donut holes
I refuse to watch that again. I'd rather have no snow anywhere
I refuse to watch that again. I'd rather have no snow anywhere
lexxnchloe
Member
Brent
Member
Webberweather53
Meteorologist
This is one of those winters where I think a strat warm event would actually hurt us (potentially). I just don't want to lose the stratosphere support over top of the Hudson Bay vortex.
lexxnchloe
Member
Sounds good
Meaning