Weather

A thaw will continue in the Northeast Thursday, with some sunshine. A clockwise flow of air around a high-pressure system offshore will contribute to the warming.

Farther south and west, clouds and rain are expected as moisture arrives from the Gulf of Mexico and the Atlantic Ocean. Unsettled conditions may extend from the Carolinas west to Louisiana and north to Ohio and Michigan.

Arctic air will expand east across the Plains, the Mississippi Valley and the western Great Lakes. Where the cold air catches up with the rain, the precipitation will change to ice and snow, affecting parts of the central Plains and the middle Mississippi Valley into Friday night. Snow will blanket the western Great Lakes. The cold air, ice and snow will advance east into the Tennessee and Ohio valleys at night.

In the West, a storm will bring rain from coastal Washington and Oregon to central Idaho. Snow will fall across the northern Rockies as well as the high country of the Cascades. Sunny, dry and warmer conditions will prevail across the Southwest. While a breeze will blow in California, brush should remain moist after recent rains.

Snow and ice is expected to spread from the Tennessee Valley to the St. Lawrence Valley late this week. The precipitation may start as rain in many areas, but plunging temperatures will cause it to change to ice and then snow. Any wet areas will quickly freeze.