Winter Storms Afflict West Coast, Northern Tier

A tale of two storms will bring rain, snow, ice, and winds to much of the nation through midweek.

The first storm, a deep upper-level storm system, continues to push eastward across the Mountain West this morning, with its trailing cold front packing a punch of moisture across the Rockies. Heavy snowfall and breezy winds will push across the Rocky Front Range through midday today. At its hind quarters, a second storm system and cold front has already begun moving into the Pacific Northwest, bringing another round of rain and snow to the West Coast and Mountain West through Wednesday. Isolated thunderstorms are also expected along the West Coast and within California’s Central Valley.

By Thursday morning, 1 to 2 inches of additional rainfall will be common across the vast majority of the Pacific coastline and the bullseye of California’s Central Valley. Lesser showers, dropping well below an inch of rain, are expected in lowlands across the Western U.S., such as the Willamette Valley and the Great Basin.

Areal Flood Advisories remain in effect for parts of southern California, while Coastal Flood Advisories are posted for most of the San Francisco Bay as well as Santa Cruz to north of Cambria, Cali. Additional rain approaching an already saturated West Coast may result in mudslides and flooding in urban, low-lying, and coastal areas. Remember, if you see flooded roadways, “Turn Around, Don’t Drown!”

Significant snow additions will pack slopes from the Coastal Range to the Rocky Mountains. The bullseye of snowfall will continue to bury the Sierra Nevada in walls of snow, with 3 to 8 feet or more of snow packing through Wednesday night! Snow totals of 1 to 3 feet are expected to pile onto ridges along the Cascades, the coastal ranges of northern California, the Wasatch Range, Arizona’s Mogollon Rim, the Rocky Front Range, and the Rockies of central Idaho and western Wyoming.

Amounts of 6 to 12 inches will blanket areas farther down these slopes, while lesser snow peppers the mid-elevations of the Rockies, the Blue Mountains, the coastal ranges of the Northwest, and the Columbia Plateau. Snow elevations will progressively lower west of the Rockies as colder shifts across much of the Western U.S.

Winter Storm Warnings and Winter Weather Advisories have been issued for most mountainous terrain west of the Great Plains aside from the northern Cascades, as well as a Freeze Warning for the southern coast of Oregon.

The first storm cold front and its trailing winds will fight with a regime of southerly winds today, leading to strong wind shifts across the Great Plains. High Wind Warnings and Wind Advisories cover many elevated areas across the Southwest, the Rocky Front Range, and even the High Plains from New Mexico and Oklahoma to Montana and North Dakota! There are also Blowing Dust Advisories posted for western Texas and southeastern New Mexico.

The first storm system itself will exit into the northern Plains around midday today, and as moisture to rushes to the Northern Tier states, wintry precipitation will ignite near the Canadian border along a stalled front. This skinny line of precipitation will grow nearly due eastward, entering the northern Great Lakes by tonight and southern New England by Wednesday afternoon. Folks under this curtain of storms will observe rather well-defined zones of rainfall, freezing rain, sleet, and finally snow farthest north.

When all is said and done, 3 to 7 inches of snow will be common across northeastern Montana, northern North Dakota, the northern half of Minnesota, northern Wisconsin, Michigan’s Upper Peninsula, the Adirondacks, and northern Appalachia. However, locally higher amounts of 7 to 14 inches are possible, especially closest to the U.S.-Canada border. Additionally, an alley of disruptive ice accumulations will likely form between parts of eastern North Dakota through areas of southern New England by Thursday morning, with locally significant accumulations possible in northern Michigan.

Winter Storm Advisories and Winter Storm Warnings have been issued from northeastern Montana through northern North Dakota, as well as across northeastern Minnesota, northern Wisconsin, the Upper Peninsula of Michigan, and northern Lower Michigan. There are even a few Blizzard Warnings across northeastern Montana. Winter Storm Watches are also in effect across northeastern North Dakota and northwestern Minnesota.

Snow combined with gusty winds will lead to difficult travel, including icy, snow-packed roads and near whiteout conditions.

Be sure to download the WeatherBug app to stay up to date on the latest on this changing weather. It’s never too early to have a supply kit packed in case of inclement weather. A simple kit including a weather radio, water, blankets, batteries, and non-perishable food items will go a long way in the event of a power outage.