Flood Watch: 2+ Inches Of Rain Forecast Across Puget Sound

SEATTLE — Heavy rain will bring fresh flood concerns over the next few days after one more brush with lowland snow passes early Thursday, according to the latest forecasts.

The National Weather Service expected most lowland areas south of Whatcom County, and away from the Cascade foothills, would see just a trace of snow before precipitation changes over to widespread rainfall Thursday morning and lasting into Friday. The Bellingham area could pick up another 2 to 6 inches of snow, while Snoqualmie and Stevens could see between 15 and 30 inches.

Forecasters expect an incoming warm front will stall over Western Washington Thursday, sending snow levels higher and making for a very rainy day across the region, particularly from Seattle southward. A flood watch will be in effect from very early Thursday until late Saturday afternoon, as snowmelt increases and area rivers experience rapid rises.

"Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations," NWS Seattle wrote Wednesday. "While most flooding that does occur will be minor, some moderate and even major flooding is forecast. Melting lowland snow will contribute to the flood potential and to soil saturation and thus, increasing the threat of landslides."

Much of the lowlands could see between 2 and 3 inches of rainfall by Friday morning, with totals likely higher around Olympia and Southwest Washington. Forecasters said flooding chances were highest for the Skokomish, Chehalis, Skookumchuck, Newaukum and White Rivers, with major flooding possible along the Chehalis and Newaukim rivers by Friday.

Significant flooding is also possible along Issaquah Creek, which city officials warn could have similar impacts to the floods of February 2020.

Fortunately, rain and mountain snow will taper off Friday, allowing the region to dry off through the weekend and potentially beyond.

"Upper-level ridging takes over for the weekend for mostly dry conditions through Sunday and into Monday," NWS Seatle wrote. "A couple of weak, dissipating fronts may reach the area Monday through Wednesday but will likely not be anything to be concerned about."