ANCHORAGE, Alaska (Reuters) - A storm experts compared to a Category 3 hurricane lashed the western coast of Alaska on Wednesday, ripping roofs from buildings and pushing water and debris into communities, authorities said.

The storm, which began hitting Alaska late on Tuesday after building over the northern Pacific Ocean, brought winds measured at up to 89 miles an hour and flooded parts of some Native villages along the coastline.

There were no reports of deaths or injuries as of Wednesday evening, and damage tallied so far was caused largely by wind and included reports of tin roofs flying off and power lines down, authorities said.

Alaska opted out of participating in a nationwide emergency-broadcast test on Wednesday due to the storm, the Federal Emergency Management Agency said.

"This is a storm of epic proportions as it's being described," said Jeff Osiensky, a meteorologist and regional warning coordinator for the National Weather Service. "This is kind of ratcheted up to a level much higher than we've been accustomed to."

"I think this would probably be about a category 3 type hurricane if we were to do some sort of a similar comparison," he said. "It's on the line of a pretty destructive hurricane."

Osiensky said that by Wednesday evening wind speeds were diminishing but water levels would remain high and new surges of floodwaters were expected.

Most of western Alaska was considered at risk, from the Yupik Eskimo community of Bethel in the Yukon-Kuskowim delta to the Inupiat Eskimo village of Wainwright on the North Slope, according to the National Weather Service.


One of the hardest-hit areas so far was Nome, a former Gold Rush boomtown famous as the end of the Iditarod Trail Sled Dog Race, and its surrounding villages.

There, the storm tossed debris onto roads, making driving dangerous, city officials reported. Waves launched "fist-sized rocks" and logs up to two feet in diameter onto the roadway, officials said.

"These objects would cause injury to any person that was struck," the city's emergency managers said in a statement.

Evacuations have been ordered in low-lying parts of Nome and other sites, with residents housed in schools and other public buildings. But large-scale evacuations out of the region are not considered feasible because weather conditions make flying hazardous, a state official said Tuesday.

Nome, with 3,600 residents, is one of the largest cities in western Alaska. The communities spread along the coast line are mostly traditional Native settlements, with a few hundred to a few thousand inhabitants, and no roads linking communities.

The Alaska Division of Homeland Security and Emergency Management set up an incident command to respond to the storm. The U.S. Coast Guard has stationed helicopters and cutters in the region to aid mariners involved in the crab fishery.

The Alaska National Guard activated an operations center at Joint Base Elmendorf-Richardson in Anchorage.

Powerful storms of this magnitude are common at this time of year in the Bering Sea and North Pacific, but this storm was unusual because of its northward trajectory and the lack of sea ice in near-shore areas like Norton Sound off Nome, National Weather Service and other agency officials said.

The last time a storm of a similar magnitude was sent in the same northward direction was in November of 1974, but the sea surface was much more frozen then.

Arctic sea ice this year reached the second-lowest coverage since satellite records began in 1979, and current ice coverage in Norton Sound and Kotzebue Sound off Alaska's western coast is sparse compared to past years at this time, according to the National Snow and Ice Data Center in Boulder, Colorado.

"Forty years ago, a big storm like this would come through and the sea ice would act as sort of a buffer," said Mark Serreze, director of the Snow and Ice Data Center.

"The Bering Sea has and always will have these strong storms. What is different now is their potential destructiveness as you lose the sea ice cover," he added.

(This version corrects spelling of meteorologist Jeff Osiensky on second reference in paragraph 7)

(Editing by Dan Whitcomb and Peter Bohan)

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