Snow Map Shows States to Be Affected During Arctic Blast

A map of estimated new snow depths across the U.S. shows another arctic blast of cold air from the north will bring at least an inch of snow across a swath of northern America by Saturday.

The model, produced by the National Weather Service (NWS) on Wednesday, indicates that as of noon (ET) Saturday more than 32 inches will have fallen across the Cascades mountain range in Oregon and Washington, as well as parts of Idaho, western Montana and Wyoming.

The Great Lakes region is also expected to see high snow accumulations, with as much as 21 inches in parts of western New York.

The arrival of an initial Arctic air mass over the weekend brought dangerously cold windchills to central states and facilitated winter storms elsewhere, including a wintry mix of precipitation in the Southeast and lake-effect snow—caused when a cold air mass moves across long expanses of warmer water—downwind of the Great Lakes.

Another surge of Arctic air is predicted to arrive over the Great Plains on Thursday before hitting the South on Friday. It will bring a chance of continued mountain snow for the Northwest and lake-effect snow for the Great Lakes region.

In its latest forecast, the NWS said that a cold northwesterly flow would bring bands of heavy lake-effect snow of up to 3 feet through Thursday night, with areas downwind of Lakes Erie and Ontario of particular concern.

At the same time, dangerously cold windchills are expected to cause the mercury to plummet across much of the U.S., with the risk of frostbite on exposed skin in a matter of minutes in the worst-affected regions.

The snow map shows that between 1 and 3 inches are anticipated to fall across the northern Plains and into the Midwest between Wednesday and Saturday at lunchtime, with slightly higher totals in the mid-Atlantic states and New England.

Snow accumulations will increase in the West, with up to 19 inches expected in north-central Colorado, 30 inches in western Wyoming and possibly more than 29 inches in western Montana into northern Idaho.

The Cascades will see the highest total, though, with 69 inches along the range east of Portland, Oregon, and Olympia, Washington.

The region has already been battered by a series of powerful atmospheric river storms, and two more are predicted to make landfall on Wednesday and Friday. Snowfall in the Northwest is expected to reach a rate of 2 inches an hour in the coming days.