WARNING OF INCREASED RISK OF LANDSLIDES IN WESTERN WASHINGTON March 06, 2014
Work crews clean up after landslides at Mt. Index Riversites in Index, WA in January. Photo courtesy Arthur Testov from Mt. Index Riversites.
(SEATTLE, WA) -- The National Weather Service says the heavy rains expected to continue through Thursday will lead to an increased threat of landslides in western Washington.
The rainy period over the last several weeks and the rainfall of 1 to 6 inches over the past 3 days has increased soil moisture to high levels across western Washington. Heavy rainfall is expected to total 1 to 3 inches by Thursday and that amount will put extra pressure on soil instability.
Cumulative rainfall over the last week has soaked soils to the point where the Washington landslide risk level is at elevated levels and increasing and the predicted rainfall might be enough to act as a trigger for landslides.
Several landslides have already been reported in various locations in western Washington and more are possible.
With an elevated landslide risk, rainfall induced landslides are possible during bursts of intense rainfall or when there is heavy rainfall over a period of a day or two as noted in the forecast.
A gradually diminishing risk of landslides will continue for several days after the rain ends. Areas most susceptible to landslides under these conditions are steep coastal Bluffs, other steep hillsides and where hillsides have been cut back for roads.
For more information about current conditions visit www.Weather.Gov/Seattle select hydrology and then scroll down for the links to the landslide information pages.
To report landslides to the state for tabulation go to the Washington state landslide risk web Page and the link for reporting.