El Niño begins to develop as the southerly storm track begins Thanksgiving week

This has not been the case yet in 2023; Temperatures have been erratic this fall and drought is increasing in the Four Corners region and the southeastern quarter of the country. Only the Southern Plains managed to escape the drought through multiple systems that dumped widespread rain over much of Texas and Oklahoma.

We may be starting to see a shift in this top-level pattern in some of the longer-term computer models. Starting late next week, an upper low is expected to form over the Aleutian Islands. In response, the jet stream splits into two, one heading north across Canada and a stronger one diving into California and blasting across the southern half of the United States

This is what we expect to see in light of the strong influence of the El Niño phenomenon. This means a more active southerly storm track and increased precipitation over the southern tier of the country starting next weekend in the lead-up to Thanksgiving, and continuing through early December. The northern jet stream should keep any bottled-up polar air toward the North Pole and bring warmer conditions to the country’s northern tier.

Whether or not this pattern will continue is a question mark. However, history indicates that December is a very consistent month. Weak, moderate, and strong El Niños all share similar characteristics to December. It is usually too warm for most of the United States outside of the Southwest where it is cooler, while increases in precipitation are seen across the Southern Tier. As this feature matures in 2024, we may see the track extend to the south, bringing less precipitation into the Ohio Valley and Great Lakes, also a typical feature of El Nino. You can read more about that here: https://www.dtnpf.com/….

In December, the storm track farther south was not clear and DTN expects near or above normal precipitation in this area. It is expected to be a very active month and Arctic air infiltrations are likely to be limited or absent.

This doesn’t mean that December will be warm every day, or that it won’t snow, but it does mean that the chances of a white Christmas are less for most of the country outside the Mountain West. We’ll just have to see if forecasts follow this pattern or deviate from it in late December. But the beginnings of an El Niño winter in North America are now in sight.

To find more of your local weather conditions and forecasts from DTN, head to https://www.dtnpf.com/…

John Baranick can be reached at john.baranick@dtn.com

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