Another 2 to 4 inches of rain expected in the Cascade Mountains overnight will raise the chance of lowland flooding and mudslides, according to the National Weather Service.
Meteorologist Johnny Burg said freezing levels of about 7,500 feet in the Central Cascades and 6,000 feet in the North Cascades will add to the flooding potential, “because this is all coming down as rain, not snow, and flowing right into the rivers.”
Seattle-Tacoma International Airport had nearly half an inch of rain Saturday by 4 p.m., and could get another inch overnight, according to the weather service’s 3:30 p.m. forecast. Coastal areas could see 1 to 3 inches of rain overnight.
The weather service issued a “flood watch” for Western Washington rivers, and warns that landslides could occur as saturated slopes give way.
As of 4 p.m. Saturday, the airport had 4.25 inches of rain so far in March, surpassing the normal amount for all of March, 3.72 inches.
A succession of mudslides at Mukilteo has halted rail passenger service between Seattle and Everett until at least 4:30 p.m. Monday.
Gus Melonas, spokesman for Burlington Northern Santa Fe Railroad, said this was the ninth track closure in that area caused by slides this season, compared to more than 60 last winter. He said the railroad did extensive slope stabilization work to reduce the number and severity of slides.