SEATTLE (AP) -- A rare tornado damaged industrial buildings south of Seattle as an unseasonable September storm dumped record amounts of rain and temporarily knocked out power for thousands in the Pacific Northwest.
The tornado at 7:20 a.m. Monday hit the industrial area of Frederickson, tearing a hole in the roof of the Northwest Door factory, blowing out car windows at a nearby Boeing factory, and damaging a building where sections of a downtown Seattle tunnel project were being assembled.
There were no injuries at those buildings or at nearby homes, where trees also fell.
A team from the National Weather Service office in Seattle went to the scene and confirmed the tornado from eyewitness accounts, meteorologist Johnny Burg said.
The Weather Service classified the tornado as an EF1, with a maximum wind speed of 110 mph.
The damage, including a jagged 40-by-40-foot hole in the roof at Northwest Door, stopped work at the factory that makes garage doors. About 100 workers evacuated.
"It looked from the inside like a wave going along. You could actually see the roof flexing," Northwest Door President Jeff Hohman said.
Work at the Boeing plant resumed while repairs were underway. There was no damage to parts or equipment, Boeing spokesman Doug Alder said.
The tornado blew out the windows of about two dozen cars in the Boeing parking lot. Several thousand employees work at the Frederickson site, which makes parts and sections for just about every Boeing airplane, including the vertical tails for the 777 and 787.
The tornado also ripped off one-third of the roof and destroyed a metal garage door at a tent-like structure in Frederickson where a company called EnCon is welding rebar cages for use in the tunnel project under downtown Seattle. Project manager Kasandra Paholsky said the damage forced work to halt but ultimately will not affect the schedule for digging the Highway 99 tunnel.
Washington may get a tornado or two every year, but they are usually small. One of the largest was an EF3 in 1972 in Vancouver that killed six people.
Parts of the Northwest got more rain in a day or two over the weekend than typically falls in the entire month.
"We basically had conditions well off shore that were very reminiscent of late fall-early winter," said Dana Felton, a meteorologist at the Weather Service office in Seattle.
It's been the wettest September on record in Seattle and Olympia, Wash., and in Portland, Ore.
As of Monday evening, Olympia recorded more than 9 inches, topping a 1978 record and swamping the usual 1.7 inches that fall in that time, the National Weather Service said. Sea-Tac Airport's September rainfall total hit 6.16 inches by 6 p.m. Monday, beating a 1978 record of 5.95 inches. Downtown Portland saw 6.82 inches by Monday evening -- the most since record-keeping began in 1872.
Puget Sound Energy had about 12,000 customers out of service late Sunday, the Bellevue-based utility reported. Seattle City Light reported it had about 3,200 customers out of service over Sunday night. Portland General Electric said it had restored more than 110,000 outages since the storm began.
The storm brought the first significant snow of the season to the mountains.
Gene Johnson, Tim Fought in Portland contributed to this report.
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