The long range European model shows colder than normal winter Alaska to the far northwestern US, while the southeastern half is warmer than normal.
It also shows the continued theme of above to well-above normal precipitation in our region & across the Ohio Valley & then over the High Plains to Pacific Northwest & western Canada.
It shows dry, drought conditions over the southern part of the U.S.
The U.S. long-range model shows colder than normal winter Pacific Northwest, far Northern Rockies & through western Canada & warmer tha normal winter over the Eastern & Southeastern U.S.
Similar in the European, it shows the wetness in the Midwest & Ohio Valley, through the Northern Plains to Northwestn U.S. & dry, droughty conditions from California to the Deep South.
When we analog similar years since 2001, we see the pattern of colder than normal conditions from the Northern Plains to the Northwest & warmer than normal conditions over the eastern U.S.
Analog shows wetter conditions in the 2001-2020 analog shows wetness farther south in the West, but still wetness in the Midwest & Ohio Valley & dry, drought conditions across the southern U.S.
When we combine similar years back to 1970, we see similar colder conditions over the northwest half of the U.S. & warmer conditions in the eastern U.S.
Similar years back to 1970 show a tendency for wetter than normal conditions in the Northwest U.S. & Ohio Valley, but dry conditions in the southern U.S.
Notice that in this La Nina situation that intense convection (heavy rain & storms) tends to occur frequently between 120-150 E in winter. In this situation, MJO has much influence.
This means lots of occurrences of the Phase 4-5 MJO December-January-February.
Cool-season MJO phases (November-March):
Phase 4-5 in December-January-February gives you a difference result in our weather compared to say May, June or July or September or October.
These two phases promote below normal temperatures in the West & above normal temperatures in the East.
Other factors like the PDO, PNA, NAO, AO & overall core of the La Nina will determine exact placement of the great temperature anomalies. However the trend is for the colder in the Pacific Northwest & northern Rockies to Northern Plains.
These MJO phases promote above normal precipitation in the Pacific Northwest, Northern Rockies, Midwest & Ohio Valley.
Other factors combined should promote core of the wetness to Midwest & Ohio Valley & in a band from Washington & Oregon to the Dakotas.
In examining the NAO, a positive mode means milder, wetter conditions for the Eastern U.S.
A positive NAO tends to occur with a horseshoe-shaped cold anomaly to the south of Greenland to the eastern Atlantic with warmth elsewhere at the SST & surface air temperature. The warmth anomaly occurs in the middle of the horseshoe.
We see horseshoe-shaped anomaly projectd in that area from south of Greenland to Portugal to the Azores & westward toward the Leeward Islands with much warmth in the middle of the horseshoe.
Also, note where much of the Arctic sea ice is located & where the greatest amount will be located this winter.
It is west & northwestern part of Greenland & westward.
This also promotes a positive NAO.
This ice configuration puts the coldest temperatures over northwestern Greenland & westward in northeastern Canada.
This means positive AO, as well, which promotes warmer winter in the eastern U.S. & colder winter in the northwestern U.S.
This means warmer winter in over much of Europe & Russia, as well, but colder summer North Africa to India & colder winter from China to Japan & North & South Korea.
It promotes wet winter over the northwestern U.S. & Rockies to Midwest & Ohio Valley & dry, droughty weather in California to Florida.
So, it only enforces the already wet, milder pattern expected for our region.
So, the takeaways are:
1. One rough, snowy winter from the Pacific Northwest (also, flooding risk there) to Northern Rockies (higher avalanche danger compared to normal) to the Northern Plains. I do think the above normal snowfall will extend to Minnesota & Wisconsin.
2. Elevated flood risk in our area for winter to early spring & elevated risk of cool-season severe weather events December to April.
3. Highest severe weather risk in spring since the early 2010s.
4. Milder winter here with tendency for below normal snowfall for winter & overall snowfall season (runs October to April).
So, it tends to mean below normal snowfall for us for the winter & overall snow season (October to April). However, given the abundance of moisture, all it takes is one of these moisture-rich storms to track a hair more to the southeast & our temperatures only 32-33 for a random heavy snowfall.
I always go back to the February 1998 southern Indiana to Kentucky snowstorm when in the unusually mild winter with trees budding & daffodils blooming at the time in that area & a storm dumped 22.4" snow on Louisville & up to 20" of heavy, wet, gloppy snow over a 3-day period in that region. I documented it in my weather records back home at 17 years old of 5.8" measured of "gloppy slush" on the "blooming Red Maples & American Elms". Our Japanese Yew shrubs were also blooming at the time. In the 1992-2008 period of records there, 1998 tied with 2001 for the earliest blooming of our yellow daffodils at home (February).
So, you can have a wet winter that is overall warmer than normal with below normal snowfall & have one big snow event of +7".
This still gives you all snow lovers hope, but it also gives hope to you all that do not like snow!