It's May, but people in parts of Colorado, Wyoming and the Midwest had to dress for winter Wednesday.
A May Day snow storm has been making travel difficult on Colorado highways, where several crashes have been reported, and along Interstate 80 in southeastern Wyoming. Denver's airport reported about 50 flight cancellations, and other flights have been delayed for de-icing.
By midday, more than a foot of snow had fallen at Rocky Mountain National Park. The heavy snow caused power and heat outages there and in Cheyenne, Wyoming, which received 15 inches of snow by noon Wednesday.
South Dakota's largest city, Sioux Falls, got its first May snowfall in 37 years. A winter storm warning was in effect for parts of Minnesota and Wisconsin, while snow fell in Nebraska, and western Iowa was expecting snow into Thursday morning.