One last blast of arctic air will freeze the Midwest and the Northeast before things begin to warm up — way up. Temperatures will swing from 20 degrees below normal Monday night in some areas to more than 15 degrees above normal by the end of the week, forecasters say.
A jet stream pattern pushed frigid air south from Canada last week, sending temperatures plummeting from Texas to Maine. The pattern is expected to mean more snow Tuesday for interior New England, with a mix of sleet, freezing rain and rain across Pennsylvania and southern New England. Farther south, bitterly cold temperatures will ice over the upper Midwest and the Great Lakes, sending lows below zero in many places through Wednesday.
But then the dominant air pattern will shift, allowing warmer air to sweep out the ice across the continental U.S., said Ari Sarsalari, a forecaster for The Weather Channel. "The nice thing is this pattern that we've got coming up this week is it's actually going to change things a little bit," Sarsalari said. "Once we get into later this week and the weekend, it's going to be much warmer through a good chunk of the country."
How much warmer? In Minneapolis, where it was 9 below zero on Tuesday morning, the high is forecast to hit 36 by Friday. Omaha, Nebraska, was at 4 below but will jump to 48 by Friday. Washington, D.C., could be in the 50s by the weekend, and even Buffalo, New York, could hit 40.
— M. Alex Johnson