Cool, damp weather on the way to Seattle, western Washington with some snow for the highest elevations

A strong, cold storm system (for late August) will bring widespread wetting rain to western Washington, chilly temperatures and even some snow to the highest peaks in the Cascades.

The culprit for the active weather pattern is a potent upper area of low pressure off the Pacific Northwest coast that will keep the region unsettled through Saturday. This low pressure will send a couple disturbances into western Washington on Friday. The first one is traversing the area Friday morning with another Friday evening and then the main upper low moves inland over the weekend. This will act to keep a strong onshore flow in place creating cloudy skies and even some fog, bringing cool temperatures and keeping periodic rain chances in the forecast.

The most widespread heavy rain arrives overnight Friday into the first half of Saturday. By the time it's all said and done, western Washington will see a widespread quarter to half an inch of rain with heavier amounts from North Puget Sound (Everett north) to the Canadian border, the foothill communities and the Cascades where 1-2 inches are possible. The highest peaks in the cascades will see snow overnight Friday into early Saturday. Light accumulations are possible (well above pass level) with several inches for Tahoma (Mount Rainier). Keep this in mind if you're hiking or camping in the mountains. A few lightning strikes are possible anywhere in western Washington Friday and Saturday. Temperatures Friday and Saturday will stay mainly in the 60s, just a few degrees off from record cold daily high temperatures. A gradual improvement and increase in temperatures begins on Sunday into early next week.