Not so holly, jolly for travelers affected by weather

It'll be a white Christmas for the northern Plains and some Western states, but it's likely to cause troublesome travel.

A large swath of the Dakotas is under a blizzard warning Sunday and Monday, with the National Weather Service forecasting heavy snow and strong winds. To the east, parts of central Minnesota are under an ice storm warning.

Much of Idaho and Montana is under a winter storm advisory, and Utah and the northeast corner of Colorado are under a winter storm warning.

Depending upon the speed and the track of the storms, this could mean heavy snow for Colorado’s central mountains Saturday night and Sunday. The chance of snow in Denver is not as great as it was a couple of days ago, but there is still a chance.

Forecasters cautioned drivers to keep alternate routes in mind and prepare for possible delays. Air travel wasn't yet impacted Saturday at the nation's major airports.

The Storm Prediction Center cautioned that warm, humid air could cause severe weather in the lower Plains, Arkansas and Oklahoma on Sunday.