You may recall that this past summer I mentioned that the upper air configuration resembled that of 2009. The temperature alignment nationally was the same, except that overall the readings averaged warmer, as if the atmosphere merged the JJAS 2011 averages in with those that appeared 14 years previous.
After that brutal display of heat in the southwest and south central states we have seen some cold frontal passages in later September and October. Another, stronger cold intrusion will drop out of Canada around Halloween, and there is at least a chance that parts of the northern High Plains and north central U.S. see some important snowfall to go with a modified Arctic air mass. But the Southwest and Southeast are not likely to b affected by the cA regime. And therein lies a clue to teh expected outcome of the winter of 2023-24.
In a “typical El Nino” weather pattern, those two regions should see much more precipitation and cooler temperatures. Ridging would usually align from British Columbia into Quebec and New England, cutting the lower 48 states out of any blasts of very cold air. Yet the 11-15 day range has the cold getting down into Texas and the Ohio Valley/Mid-Atlantic. The 500MB flow does not split.
Most of November will turn out to be quite mild and dry as the unified jet stream takes a semizonal turn, bringing nearly everyone air from the Pacific Ocean that loses moisture crossing the Rocky Mountains. My suspicion is that in the days after Thanksgiving, the flow buckles again, and colder air and a Mexico to the Deep South storm track sets up. It may not be as cold as the winter of 2009-10, with periods of warming in between disturbances. But this is not a Super El Nino, and 1982-83, 1997-1998 and 2015-16 analogs do not seem to fit.
Have a wonderful weekend while I finish writing the final draft of my winter outlook!