Posted December 27, 2017 7:45 p.m. EST
Very cold air will extend from the Northeast and interior South to the Midwest and central and northern Plains on Thursday. A large southern dip in the jet stream will continue to funnel air south from the Arctic and into the United States. Within this mass of frigid air, an Alberta clipper storm will sweep across the north-central states with snow from the northern Plains to the western Great Lakes. In most cases, snowfall from the storm will be 3 inches or less. Relatively light winds will result in minimal lake-effect snow. Winds are likely to stay light until a second clipper storm with snow passes by on Friday night. On the southern edge of the cold air, rain is forecast to linger over the Deep South. Freezing rain and sleet may develop in parts of Georgia and the Carolinas later Thursday and into the night.
In the Northwest, rain is forecast for coastal areas of Washington and northern Oregon, while snow falls on the northern Cascades and the interior. This snow will extend across the northern Rockies as well. A plume of moisture will continue to stream in from the Pacific Ocean into this weekend. However, it is not forecast to dip very far to the south and certainly not into Central and Southern California for the first week of the new year.
FOCUS: New Storms for the Northwest
A pair of storms will move into the Northwest late this week bringing nearly a foot or more of snow in the Washington Cascades and northern Rockies. Rain will soak the Interstate 5 corridor, while ice will glaze the interior valleys of Washington and northern Oregon.