The cold air that has been sitting across the northern Plains will make a big push southeastward on Tuesday, bringing much-colder air into much of the Midwest.
Places in for a much-colder day on Tuesday include Chicago, Ill., St. Louis and Kansas City, Mo., Des Moines, Iowa and Oklahoma City, Okla.
Temperatures across much of the Upper Midwest will be 15 to 25 degrees below average on Tuesday afternoon. Cities like St. Louis and Kansas City that had high temperatures in the 70s on Monday will likely only be in the 40s on Tuesday afternoon.
In fact, it will be cold enough for some wet snow to mix in with rain showers around Kansas City on Tuesday. With temperatures above freezing, no accumulation is expected.
The biggest change will likely be in the Texas Panhandle, where a high near 90 degrees on Monday in Amarillo will be replaced by temperatures in the 40s on Tuesday afternoon.
To add even more shock to the system, winds gusting over 20 or even 30 mph will make it feel even colder.
A hard freeze is expected on Tuesday night across western and southern Kansas as well as the panhandles of Texas and Oklahoma, with low temperatures reaching record levels in some locations.
The chilly weather will be the result of a cold front pushing through and an area of high pressure building across the Rockies. The flow around that high will bring a cold, northwesterly flow into the Midwest.
This northwesterly flow is going to tap the same cold air that has prevented Bismarck, N.D., from getting above the 40-degree mark for the past nine days.
The good news for those tired of the cold is that things should improve by the end of the week.
The same area of high pressure responsible for the cold on Tuesday and Wednesday will slide eastward by Thursday. A southwesterly flow around the back side of the high will usher in warmer air for the end of the week and the weekend.
Story by AccuWeather.com meteorologist Brian Thompson.