Factors considered: MEI, AMO, PDO, QBO, Solar, Fall Pattern
Factors weighted heaviest: MEI, Solar, Fall Pattern
MEI, AMO, PDO, and QBO are all in a neutral, weak, or transitory phase. Solar is in an unusually quiet phase, relative to the past 100 years.
As has been discussed on this forum at length, the number of analogs that check many boxes this year is very small. Therefore, this is a heavily blended analog forecast, using years that are very different in terms of some factors, but have some important commonalities in the factors I believe are most important this winter.
Strong signal for cold anomalies centered in the northern Plains/Rockies, likely extending to the PNW at times. Southwest looks near normal; very little in the way of warm anomalies for the country except perhaps the far southeast. Wetter than normal in the SE, northern plains/rockies, and probably CA. Drier than normal in the PNW (especially further north), and the central/southern plains.
Cold anomalies centered in the southern plains/lower Mississippi valley, with lesser cold extending across most of the West and the South. Near normal in the upper Midwest, and best chance of warm anomalies is in New England. As far as precipitation, the east coast looks wet and stormy, much of the midwest drier than normal along with the PNW and northern Rockies, and a little wetter than normal in the southwest.
Mixed signals this month, but leaning heavily towards cold for most of the East, and a decent chance of cold in the southern Rockies/Southwest. Northern Midwest and possibly the northern Rockies look like the most likely places to be warmer than normal. Most of the West should be drier than normal, along with the NE. Southern plains and the South look wet.
Everything I'm looking at points to a -EPO/-NAO/-AO winter. In other words, big-time blockiness in the high latitudes. This is mainly due to low solar and weak ENSO. I'm predicting the first -NAO winter since 2010-11. I also believe it will be the coldest winter nationally since at least 2013-14 (which was no slouch). Several major, record-breaking cold waves should impact most of the nation. I also expect most of Europe to experience a very cold and snowy winter due to a dominant -NAO feature.
The southern jet should be active in spurts, with a good chance of above normal precip for the winter in the Southwest, southern Rockies, and SE. Clashes with Arctic air dropping south should make for some big snowstorms, especially for the middle of the country. I expect the December pattern to be quite variable, but January and February could see stagnant patterns lock in for extended periods.
For the PNW: I think this will be a drier than normal winter overall, with no more than one wet month most places. Higher than normal chance of a major Arctic outbreak due to overall blockiness, even though the bulk of the cold should be centered well east. I think a very snowy winter is unlikely most places, especially higher elevations, perhaps something along the lines of 1984-85, 2000-01, 1978-79, or 1976-77 (very unlikely it will be quite that dry, of course). But with plenty of cold air over the continent to tap into, you never know...