"I would not be surprised to see something around Thanksgiving or shortly after."
Obviously there was a pretty major blizzard across parts of the central U.S. and midwest yesterday. That system intensified as it moved out of the Rockies and was a little farther south than what many forecasters (and computer forecast models) had predicted. There has already been a half dozen systems or so this fall that have been stronger and farther south than what had been expected, and that just MIGHT BE the trend this winter.
Since the previous post on the 12th, the flow aloft has changed, at least temporarily. Back on the 12th there was a very amplified ridge aloft across the west coast and that has since broken down enough to allow flow aloft to enter the western U.S., bringing heavy snows to much of the Sierra Nevada range (and also to the central Rockies). On the satellite image below....
The bright area across the bottom of the image circled by blue represents deep tropical moisture, most likely associated with the warmer than average sea surface temperatures (i.e., the developing El Nino). There has been an atmospheric response/coupling from these warm waters in the form of a sub-tropical jet stream transporting energy and moisture north into the higher latitudes. In addition, there is a pretty good upper low near Guam across the central equatorial Pacific. That could be a player in the U.S. weather a little down the line. There is also a deep and strong system across the Gulf Of Alaska.
All told, the flow aloft will continue to be rather active for the next 10 to 14 days. There should be several more impacting storms across the central U.S., but details of timing, intensity and location will be unknown until they develop and enter the continent. The first may be as early as the end of this week and the following may occur towards the end of the weekend or first of the next week (Dec 2-5). Brutal cold air is not showing up at the moment. But there is a rather robust MJO developing and the impacts may be much colder air as we get into December. More on that later.
I'll try to update again by the weekend.
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