Rain at times for today-- for about an hour it might be heavy as the actual front pushes through your part of the region. High temps, quite normal for this time of the year. Mid 40s for most cities on Interstate 5. Expect to see the steady rain taper off into some scattered showers by tonight for most locations west of the Cascades.
Some dangerous weather in Central WA and NE Oregon. A winter weather advisory is in effect until 10pm BELOW 2,000. 1-2" of snow and about a tenth of an inch of ice in some locations. Ice is the most hazardous kind of weather to travel through-- so be careful in Ellensburg, Kittitas Valley, Tri-Cities, Yakima and Boardman, OR.
This cold weather east of the Cascades-- is somewhat part of the arctic blast that's affecting the Midwest and East Coast. The Rocky Mountains and Cascades provide nice protective barriers for the lowlands of the Puget Sound from the cold that pushes out from time to time from Canada onto the Great Plains and over the Great Lakes . Our polar blasts here in the NW come out of the Frasier River Valley in British Columbia to the north and through the Columbia River Gorge to our south. Also, "polar vortex" kind of outbreaks as they're calling the cold snap back east--- don't hit the west coast, mostly because we're so close to the giant Pacific Ocean. The waters in the northeastern Pacific can be mild compared to the extreme sub-zero cold. The bitter cold air masses that go over our ocean waters often moderate out the extreme cold of the air overhead. So, we're protected in two ways from the kind of cold they're seeing from Chicago to the Big Apple.
So, while they slowly thaw this week-- we're quite mild by comparison. And we're also pretty soggy. The next week west of the Cascades looks like a wet one. On/off rain pattern continues into the weekend. The periods of heaviest rain look to be Wednesday PM and Saturday early AM. This will all be rain in the lowlands and snow in Cascades/Olympics above about 3,000 ft. Enjoy!