(CNN) — Tens of thousands of people lost power in Iowa on Thursday as the first major storm of the season swept in, bringing blizzards, high winds and severe thunderstorms to the central United States.
The storm prompted the National Weather Service to issue a blizzard warning for a huge swath of the Midwest stretching from eastern Colorado to Wisconsin’s Lake Michigan shoreline, including virtually all of Iowa.
The declaration warned of snow accumulations of up to 12 inches, complemented by 25- to 35-mph winds that will occasionally gust to 45 to 50 mph.
More than 30,000 people were without electricity Thursday morning in Iowa, the bulk of them in Des Moines, according to MidAmerican Energy.
Iowa has seen the highest levels of snow so far, the National Weather Service said, with more than 8 inches in places.
Travelers who have hit the road early for the holiday season may face challenging conditions.
Gov. Scott Walker declared a state of emergency in Wisconsin ahead of the storm, mobilizing the Wisconsin National Guard, the state patrol, Wisconsin Emergency Management and other state agencies.
The Wisconsin State Patrol and National Weather Service have urged people to avoid traveling.
“Mobilizing our state agency resources during this storm will ensure we leave nothing to chance when it comes to protecting the citizens of Wisconsin,” Walker said.
In Colorado, adverse weather has closed U.S. Highway 6 at Loveland Pass, the state’s Department of Transportation reported Thursday.
A 156-mile stretch of Interstate Highway 70 between Denver and the Kansas state line was closed in both directions for a time Wednesday. U.S. Highway 385 was closed in the Cheyenne Wells region Wednesday but reopened Thursday, Colorado’s Department of Transportation said, with warnings of high winds and icy spots.
Airlines were reporting relatively few cancellations or delays in areas affected by the storm Wednesday night, but that may change Thursday.
The storm will race into western Illinois, the weather service said. Rain will quickly change to snow as the storm advances northeast, with the heaviest snow occurring overnight.
“Snow drifts several feet deep will be possible given the strong winds,” the blizzard warning states.
Wrapping around the blizzard warning on the north, south and east is a winter storm warning, which will be no picnic either. The winds won’t be quite as strong, but residents should expect a strong dose of rain, sleet and snow, with a few hail-packing thunderstorms thrown in for good measure.
A winter weather advisory is in effect for the Indiana-Ohio-Michigan tri-state area, as well as central Missouri and Kansas.
The “intense cyclone” will crawl across the Great Lakes region Thursday and slog into northern New England by Friday evening, the National Weather Service predicted.
Another storm is beginning to affect the Pacific Northwest and northern California, where heavy mountain snow and coastal flash flooding are possible through at least Thursday, the National Weather Service said.
Dodging the heavy precipitation but not the high winds is an area from western Texas and eastern New Mexico through the Oklahoma Panhandle and into southwest Kansas.
Much of the Southwest and Mississippi Valley is extremely dry, and the high winds have kicked up blinding dust near Lubbock, Texas.
At least 17 people were sent to hospitals near Lubbock after a 23-vehicle chain-reaction crash on Interstate Highway 27 north of New Deal, Texas, state safety officials told CNN on Wednesday. There was at least one fatality, said Clinton Thetford, emergency management coordinator of Lubbock County. A stretch of the freeway in Lubbock County remains closed indefinitely.
Meanwhile, the National Weather Service in Mobile, Alabama, issued a tornado warning until 5:30 a.m. CT on Thursday for a cell that was moving directly toward downtown Mobile.
The storm has shown signs of strong rotation and could affect downtown Mobile and the Mobile Regional Airport.
CNN’s Jim Kavanagh, Laura Smith-Spark, Carma Hassan and Joe Sutton contributed to this report.