Snow over Thanksgiving holiday? When Central KY should brace for first winter blast
AI-generated summary reviewed by our newsroom.
- National Weather Service warns Kentucky will shift from mild to winter next week.
- Forecasters cite La Niña and a weakening polar vortex driving Arctic air south.
- Climate outlooks show above-normal precipitation and elevated snow chances in December.
The latest National Weather Service forecast shows the temperature high near 60 degrees in Lexington as it enters Thanksgiving week.
That said, several forecasters are anticipating an abrupt shift to winter weather around Thanksgiving, Thursday, Nov. 27, particularly over the holiday weekend. Among them is Mark Jarvis, a meteorologist with the agency’s station in Louisville, who spoke with the Herald-Leader Nov. 18.
“The winter here, it’s probably going to start off with a bang and get going fairly quickly,” Jarvis said. “We’re going to get a big pattern change here, probably starting as early as next week.”
Why forecasters expect temperatures to drop around Thanksgiving
Meteorologists are pointing to several factors to explain the seasonal shift. The two strongest are an active La Niña lingering into the start of December, combined with a weakening polar vortex.
La Niña is the cold phase of the El Niño-Southern Oscillation Cycle, or ENSO. It’s marked by unusually cool sea surface temperatures in the central and eastern Pacific Ocean, which has the effect of strengthening the trade winds that blow east to west along the equator.
In the U.S., La Niña generally lends to a warmer, drier winter across the Sun Belt, while states along its northern half experience cool and wet weather.
In addition, a weakening of the polar vortex — a swirling wall of cold air normally locked around Earth’s poles — could send bursts of Arctic air much further south in the U.S. This points to a cold start to December, the beginning of which will emerge over the Thanksgiving holiday.
“I think it’ll probably be just after Thanksgiving,” Jarvis said. “We’ll start to see colder conditions develop across western Canada and into the plains.”
There’s a strong chance of rain Monday, Nov. 24 and Tuesday, Nov. 25, the latest NWS forecast for Lexington showed Nov. 20. At the same time, there’s growing confidence cold weather will arrive here by Thanksgiving Day and linger throughout the weekend, though the details aren’t exact.
WKYT Chief Meteorologist Chris Bailey indicated the area could see light snow over the holiday weekend.
Snow lovers rejoice: Conditions are ripe for it in December
According to Jarvis, snow lovers and those who cherish cold weather have a lot to look forward to in December.
While weak La Niñas tend to a have a more variable and harder-to-predict effect on temperatures in Kentucky, additional precipitation is more of a constant, Jarvis said.
The latest available three-to-four week outlook from the Climate Prediction Center, issued Nov. 14, backs that up. Between Saturday, Nov. 29 to Friday, Dec. 12, most of Kentucky sits between the two extremes of above- and below-normal temperatures, but the entire state is leaning toward above-normal precipitation.
Combine with that with the temperature outlook, and the chances are good for snow in Kentucky next month.
“Our confidence in growing cold over the next few weeks is really good,” Jarvis said. “The depth and the extent of it and how extreme it will be, that’s still a bit unknown, but should come into clearer focus as we [get] further into late November and into December.”
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