Weather

A snowstorm will spread across the Midwest and mid-Mississippi Valley on Sunday and into the Ohio Valley and Great Lakes as the day progresses. The system is expected to swing eastward late in the day and at night. A cold rain will break out along the mid-Atlantic Coast, though mainly snow will fall west of Interstate 95 in the mid-Atlantic states and in New England, lasting into Christmas morning.

Behind the storm, arctic air will charge across the northern Plains and into the upper Midwest, with highs in the single digits and teens across northern Wisconsin, northern Minnesota and North Dakota.

A disturbance in the Northwest will produce some snow and rain around Seattle in the afternoon, with ice expected to change to rain in the Willamette Valley. In contrast, warm weather with sunshine will persist across the Southwest.

Much cooler air is expected in the South in the wake of a cold front, with clouds and even a little rain lingering over the eastern Carolinas. Much of the interior South will be chilly despite any sunshine. It will remain warm ahead of this front across Central and South Florida with at least partial sunshine.

Focus: Snow and Ice Threaten Northwest

As a storm pushes inland across the Northwest later Sunday, the air will be cold enough around Seattle for snow to accumulate, while Portland, Oregon, will face an icy mix. The wintry precipitation will cause treacherous travel for motorists on Christmas Eve.