Landslides Are New Weather Threat As Snow Melts In Puget Sound

KIRKLAND, WA - The threat of snow is over for now, but now a new weather threat is emerging in Puget Sound: landslides.

The snow that fell over the last 10 days put a lot of weight on slopes and hillsides across the region. Now that the snow is melting, water is saturating soil, creating the risk of collapse.

On top of the melting snow, there's a new weather system moving into the region that will bring rain on Thursday and Friday. That storm will only further saturate the ground.

According to the National Weather Service, the risk of landslides is highest on Thursday and Friday for all areas under 1,500 feet. Areas above 1,500 feet will see snow and colder temperatures. For reference, the Cougar Mountain summit is at about 1,600 feet.

"Melting snow is very efficient at increasing soil moisture and is not well represented in the landslide indices such that the threat is higher than the indices suggest. Additional rain [Thursday] through the weekend will put extra pressure on soil instability, leading to further increased threat of landslides," the NWS wrote in an alert.

Caption: A landslide along Maple Valley Highway in Renton in 2017.

Photo courtesy Renton police