Ted S. Warren / AP
A downed tree rests on a car Thursday in front of an apartment building in Tacoma, Wash.
Updated 3:45 p.m.: Temperatures in the Puget Sound region warmed above freezing on Friday, but tens of thousands of people remained without power after coatings of snow and ice took down power lines and trees around the region.
The Tacoma Narrows Bridges between Tacoma and the Kitsap Peninsula were closed because ice was falling from the upper structures and cables on to the roadway, NBC station KING/5 of Seattle reported.
Sea-Tac Airport re-opened all three runways Friday after a layer of ice forced the airport to shut them down Thursday. But there was still a significant backup of flights.
Schools in the Seattle area were closed for a fourth straight day during a week already shortened by the Martin Luther King Jr. holiday on Monday.
In western Oregon, flooding rivers were expected to start to recede as the state got a break in rainstorms through Friday afternoon, said Nick Allard, meteorologist at NBC station KGW of Portland.
Original post: Utility crews worked Friday to restore power to hundreds of thousands of Pacific Northwest residents left in the dark by a powerful snow and rain storm.
About 250,000 electric customers around Seattle, Tacoma and Olympia were expected to begin a second day in the cold and dark. Most of those affected are customers of Puget Sound Energy, which said it could take into the weekend or later to get the power back on for everybody.
The storm coated much of Washington in ice and swelled Oregon rivers, killing a child and two adults. Besides the outages, the big concern now is more flooding in both states with warmer temperatures and rain.
The National Weather Service said warming temperatures Friday should melt snow and ice in the Western Washington lowlands as the forecast returns to normal — rain — into next week. Forecasters said the melting snow could cause urban and small stream flooding and fill the Skokomish and Chehalis rivers above flood stage by Saturday evening.
Gov. Chris Gregoire of Washington and Gov. John Kithaber declared both a state of emergency, authorizing the use of National Guard troops if necessary.
Oregon, which saw the storm heap a torrent of rain on top of melting snow, should see a break for some hours before another front comes in, said meteorologist Paul Tolleson in Portland, Ore.
"It'll be just enough rain to make people nervous," he said.
The unusually strong system temporarily shut down Seattle's airport Thursday. Alaska Airlines and Horizon Air canceled 310 flights to and from Seattle Thursday and Alaska Air said it was canceling 50 flights on Friday. Seattle is Alaska Air's main hub.
The storm left three people dead: a mother and her 1-year-old boy, killed after torrential rain swept away a car from an Albany, Ore., grocery store parking lot; and an elderly man fatally injured by a falling tree as he was backing an all-terrain vehicle out of a backyard shed near Seattle.
Thomas Patterson / AP
Floodwaters run over Gun Club Road in Independence, Ore., Wednesday, Jan. 18, 2012. Though most of the Willamette Valley's overnight snow rapidly melted away, heavy wind and rain whipped through the region. (AP Photo/Statesman-Journal, Thomas Patterson)
The weather system also dropped snow on Washington's Mount Rainier, where four people were reported missing. A search was suspended at nightfall but was to resume Friday.
“It really is pointless to [attempt a rescue] in blizzard conditions …,” Stefan Lofgren, head of Rainier’s climbing program but not part of this search, told The News Tribune. “You can’t place people at risk in the same weather that pinned down the people you are trying to rescue.”
In Oregon, flooding hit the Salem-to-Eugene area the hardest, with 17 rivers across the region at or near flood stage, The Oregonian reported. Some 15.5 inches fell in 48 hours in the tiny Lane County town of Swiss Home.
Portions of several Oregon highways were closed Thursday due to high water or downed trees.
Rick Bowmer / AP
A submerged school bus lies on its side as Diane Garibaldi looks on Thursday in Salem, Ore. Up to 10 inches of rain fell on parts of the Oregon Coast Range in a 36-hour period.
In the Willamette Valley town of Scio, Ore., many residents evacuated as the city manager said water was pouring down Main Street.
Officials in the city of Turner, Ore., issued a voluntary evacuation order to people, asking them to flee to higher ground as floodwaters from the rising Mill Creek swept through town.
To the west of Oregon's Coast Range, residents were being moved out of Mapleton, with a population of about 900.
The storm system also brought blowing snow to northwest Colorado as high winds battered the Front Range, with more heavy snow expected over the weekend.
Meteorologist Mike McFarland at the National Weather Service in Seattle said the system that brought freezing rain was over Minnesota, Wisconsin and parts of Nebraska and Kansas Friday but not packing the same punch.
"I don't think it looks like a very interesting system back east," he said. "Even though it was interesting here, it's not an extensive storm that will do much of anything anywhere else.
"It was unusual but not exceptionally potent, otherwise."
The Associated Press and msnbc.com's James Eng contributed to this story.
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