A ferocious storm is dumping heavy snow across portions of the Rockies and northern Plains on Tuesday. Winter storm warnings are in effect from New Mexico to Wisconsin, while a few portions of Colorado and Utah are under blizzard warnings.
Meanwhile, the same storm could bring severe weather and tornadoes to portions of the central and southern Plains Tuesday afternoon and evening.
The Storm Prediction Center reports that Oklahoma City and.Wichita Falls are under the greatest threat for tornadoes and big hailstorms later Tuesday, and cities such as Dallas, Kansas City, Tulsa and Wichita could also see severe weather.
In all, about 20 million people are at risk of severe weather Tuesday.
On Monday, four tornadoes were reported in northeastern Colorado, but no injuries were reported. Farther west, wild winds from the storm lashed portions of California and Arizona, knocking out power to thousands and fanning wildfires.
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In Denver, the snow also came with a shocking temperature drop: the city reached 71 degrees Monday afternoon, but was 16 degrees as of Tuesday morning, AccuWeather reported.
With forecasters predicting 6 to 11 inches, Denver Public Schools closed all schools and offices Tuesday. Colorado's largest school district, Jeffco Public Schools, was among those canceling classes.
Denver International Airport reported more than 400 canceled flights early Tuesday and warned travelers to be ready for delays as planes were de-iced. About half of the cancellations were commuter flights, airport officials said.
Areas of snow, locally heavy, are forecast throughout the day across the mountains of Utah, much of Colorado and Wyoming, and into western, central, and northeastern South Dakota, the Weather Channel reports. Up to 7 inches of snow has fallen on Rapid City, S.D. thus far, according to AccuWeather.
An icy mix of sleet and freezing rain is likely Tuesday night for eastern Nebraska, far northwest Iowa, southeast South Dakota, and much of southern Minnesota, the Weather Channel reports. The greatest risk of significant ice accumulation should be to be in southeast South Dakota and southern Minnesota during this period.
The Weather Channel has named the storm Winter Storm Walda as part of its winter storm-naming system.
More severe weather is forecast from the storm in the Mississippi Valley on Wednesday.
Contributing: Associated Press