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Warmest and coldest January in Hamilton County, Tennessee history
2024 has started off with intense cold and severe weather across much of the U.S.
Storms caused flooding in the Northeast, tornadoes in the South, and deep snow in the Midwest and New England.
Minneapolis saw lows of -8 F over Martin Luther King Jr. weekend. Further South, Dallas experienced temperatures into the teens, unusual for a city with an average January temperature of 45.2 F.
Global average temperatures continue to increase over the long term, but the effects of human-caused climate change don’t always mean warmer winters and hotter summers. Extreme weather events can always disrupt longer-term trends. Warmer global temperatures also increase atmospheric moisture, fueling storm systems.
This frosty January comes after nearly 14% of counties experienced their warmest December on record. For another 20%, it was the second-warmest December they’ve experienced.
So what caused this spat of extreme winter weather in the first month of 2024? It’s difficult for scientists to attribute every weather event to a specific cause, but a “sudden stratospheric warming” event in the Arctic recently ruptured the polar vortex , a high-pressure system that typically contains frigid air to the North Pole. That disruption widened the span of the vortex, bringing it into parts of Canada and the U.S.—and spreading colder temperatures across the Northern Hemisphere.