Flash flood watch in effect for parts of Whatcom County
Thunderstorms are expected across the mountains and foothills of eastern Whatcom County and other parts of the North Cascades, prompting National Weather Service meteorologists in Seattle to issue a flash flood watch.
Burned areas of recent wildfires could be particularly susceptible to landslides and fast-moving water, according to a statement issued just after 10 a.m. Thursday.
“Thunderstorms will develop over the Cascades this afternoon and tonight. Storms will be slow-moving and produce high rain rates, allowing for potential flash flooding over area burn scars,” the weather service said.
Valleys and foothills of Whatcom and Skagit counties are included in the weather alert.
“Flash-flooding and debris flows caused by excessive rainfall continue to be possible over the Sourdough, Easy, Chilliwack, and Suiattle-Boulder-Toketie burn scar,” the weather service said.
In the summer of 2023, the Sourdough Fire burned more than 6,300 acres of forest in southeast Whatcom County, closing Highway 20 several times and threatening the North Cascades Institute and electricity-generating facilities for the city of Seattle.
Last summer, the Easy Fire burned more than 1,000 acres and closed Highway 20 east of Newhalem.
This story was originally published July 31, 2025 at 11:34 AM.
