More rain and wind Friday and into the weekend

Dec. 17, 11 p.m. - We’re seeing mainly rain-free conditions overnight into Friday morning but a few showers will be possible early. Rain will increase by noon and the late afternoon and evening will be soggy and pretty breezy.

Rainfall amounts on Friday will be in the 0.25-0.75″ range around Puget Sound with more at the coast. In the mountains, the snow levels will be around 3,500 feet with one to four inches of snow at Stevens Pass and probably just a slushy rain-snow mix at Snoqualmie Pass. There are no mountain snow advisories in effect for this next weather system as it will be in and out in a matter of hours.

Probably the most impactful part of the next weather system will be a period of breezes with gusts from 25-35mph with isolated 40+mph gusts mainly from early Friday afternoon through early Friday evening. Winds will be pretty much on par with what we experienced last night into early this morning or perhaps a little stronger – enough to cause some spotty power outages.

However, the one additional factor that becomes a bit more of a threat with time is how soggy the ground is getting. We will have a higher risk of shallow landslides or slips through the weekend (even if it isn’t raining) and also trees with weaker root systems could come over in the windiest times.

Friday night and Saturday morning will be another break in the action before rain increases late Saturday afternoon and continues Saturday night into early Sunday. This time period will be marked by warmer temperatures with the bonafide atmospheric river originating north of Hawaii and also snow levels in the mountains rising to 6,000 feet. It will be all rain with this event at the lower passes, but all the additional rain (instead of snow) in the mountains will run off into area rivers. Those rivers will be running at or near bankfull, and a few will flood.

While it looks like rain pushes south of the area for most of Sunday, this is the day rivers will peak with the Snohomish, Snoqualmie and Skokomish expected to reach moderate flood stage. Any impacts other than a great show at the Falls and flooding of typically low-lying areas that flood every year will be determined by whether we get that expected break Sunday. If rain continues, flooding will be worse. But right now, it looks like that break will allow for rivers to recede Sunday night into Monday.

We’ll get another more modest round of rain Monday before three days of drier weather Tuesday through Thursday. It will be chilly, but dry with early morning fog and afternoon sunshine. Frost and freezes will be widespread on several of those mornings with black ice and freezing fog issues.

Christmas Day could get rainy once again but it’s just a little too far out to be confident in a wet forecast for the holiday. If precipitation moves in, there could be a brief time of some snow mixing in with precipitation but no White Christmas appears to be in the offing.

Cox Media Group