First major fall windstorm to develop late tonight, early Monday

The first major windstorm of the fall is expected to begin developing late Sunday night and early Monday morning as a low-pressure system from the coast brings 25- to 35-mph winds to the area, along with periods of heavy morning rain and even stronger winds Monday night.

Winds are expected to taper off during the day before picking up again later in the evening Monday. The National Weather Service is predicting sustained wind speeds late Monday of about 45 mph with gusts as high as 60 mph — enough to knock out power and bring down tree limbs in some places, said weather-service meteorologist Dennis D'Amico.

The weather service has issued both a high-wind watch and a wind advisory for Sunday night through Tuesday morning. If projections play out, it will be the strongest windstorm of the season, D'Amico said.

A series of low-pressure systems off the coast also will bring strong rains and flooding to the North Cascades and Olympics, with flooding possible in Snohomish, Whatcom and Skagit counties, he said.

No flooding is expected along the Green River, and the Central Cascades should miss the brunt of the rainfall, D'Amico said.

—Katherine Long, Seattle Times staff