Heavy rains early Saturday brought a summer soaking to much of Western Washington and the Cascades, causing mudslides that closed Chinook Pass.
Seattle-Tacoma International Airport had recorded .38 inches of rain by about 10:30 a.m. Saturday, breaking the record for the date, which was .28 inches in 1965, said National Weather Service meteorologist Courtney Obergfell. It was not one of the 10 wettest August days on record at Sea-Tac, but more rain fell elsewhere: The Weather Service office in north Seattle received .65 inches.
Heavier rains fell in the Cascade Mountains. At least three mudslides closed Highway 410 in both directions east of Chinook Pass until late afternoon.
A wide band of rain stretching from the coast to the mountains moved north through the region early Saturday, spurred by a weather system that made landfall near the California-Oregon border, Obergfell said. The southern edge of that rain band was around the Everett area mid-morning, and the sun was beginning to break through late Saturday morning. Showers and thunderstorms remain in the forecast for the Cascade Mountains and foothills through the evening.
The system produced thunderstorms in Oregon and the southern Washington Cascades, including some isolated stronger ones in Lewis County. There were more than 2,800 lightning strikes associated with the storms across Washington. They did not appear to ignite any new wildfires west of the Cascades, Obergfell said.
August is a typically dry month, but Saturday’s rain was not unusual, she said. The record daily rainfall total at Sea-Tac for the month was 1.63 inches on Aug. 18, 1975, Obergfell said.