Des Moines, Iowa ? Successive waves of wintry weather gripped much of the country Saturday, frustrating holiday travelers from coast to coast and keeping the lights off for thousands of people who lost power after ice storms just days ago.

Iowa public safety officials urged motorists not to travel as heavy snow began to fall in the morning. The state expected winds up to 35 miles per hour and wind chills of minus 25 just two days after being slammed with sleet, ice and snow.

Washington state braced for hurricane-force winds as a storm blew in from the Pacific. The temperature dipped to minus 18 Saturday in Spokane, which expected up to 6 inches of snow on top of the 25 that fell over the past three days, said Johnny Burg, a National Weather Service meteorologist.

In the Northeast, the aftermath of snow that fell Friday continued to snarl air traffic. And residents who still lacked power after an ice storm last week grew frustrated as officials warned that the storm now battering the Midwest would blow in today, the official first day of winter.

But the wintry conditions weren’t unwelcome everywhere. Megan Zarbano, manager of Kratz Hardware in Valley City, N.D., noted that the snow was helping to clear inventory from years of mild winters.

“We haven’t had a blizzard-type storm in almost 10 years,” she said. “A good storm really shakes people up; they freak out and realize they’re not prepared for winter.”

North Dakota’s snowfall total for December nearly matches the 19.3 inches that fell all last winter, said meteorologist Joshua Scheck at the National Weather Service office in Bismarck.

“And it’s not even the first day of winter yet,” he said Saturday.

The cold was the major concern in Illinois, where the Weather Service canceled a storm watch in the north but warned that freezing temperatures could cause flooding from ice jams on rivers near the Quad Cities and Rockford.

Meteorologists also said the weekend’s temperatures, expected to hit minus 5 by late Sunday with wind gusts of 30 mph, could again damage power lines serving those plunged into darkness by ice earlier in the week.

More than 77,000 customers in northern Indiana still had no power Saturday after Thursday night’s ice storm, and Indiana Michigan Power said the power failures could last beyond Wednesday. The Weather Service warned that winds as high as 40 mph would “create havoc with trees and power lines” already covered or weakened by ice.