WeatherWatcher: Winter Storm Watch for Friday evening into Saturday morning, teaser Thursday night

 

Dusting of snow in Shoreline December 2009
Photo by Carl Dinse

A series of snow events is expected starting Thursday afternoon through the weekend. I'll start with Thursday afternoon. A weak low pressure system is expected to move in on the central Oregon coast on Thursday. This low pressure is far away, but close enough to send precipitation up to about the downtown Seattle area. Temperatures will be cold with the snow level at sea level so any precipitation is expected to fall as snow. 

Shoreline and Lake Forest Park are just far enough north to be outside of the expected wall of snow. We will likely have snow flurries, and some of those flurries may pick up enough to give us a dusting to about 2 inches, depending on how far north those snow showers reach. 

• If you are traveling south of Seattle on Thursday or Friday morning, those folks are under a Winter Storm Warning for Thursday evening's snow event. They are expecting 3-6 inches of snow accumulations particularly south of SeaTac through southwest Washington.

Low temperatures Thursday night are expected to be in the 20's. A chance of snow remains in the forecast through Friday morning and afternoon with high temperatures staying in the low to mid 30's.

The National Weather Service in Seattle has issued a Winter Storm Watch for areas including Shoreline and Lake Forest Park, in effect for Friday afternoon through Saturday afternoon. From the National Weather service: heavy snow is possible with 3-8 inches of accumulation possible. A winter storm watch means severe winter conditions may affect our area, but location, timing and accumulations are still uncertain.

Forecast models are pretty much locked in on the idea that Friday evening through Saturday afternoon there will be a widespread snow event. Amounts are still varying; a lot of the forecast maps show between 12-20 inches of snowfall in the Shoreline area by Sunday morning. 

• It is important to be aware that snowfall is not the same as snow accumulation on the ground. Accumulations will likely be less, but that still puts us in the range of 6-12 inches or more.

What does this mean for Shoreline and Lake Forest Park? At this time the best thing to do is be prepared for and anticipate winter weather this weekend. The forecasts will likely change as we get closer; there is a high level of uncertainty on accumulation amounts. Based on my experience I believe we will likely see close to 8-10 inches by Sunday morning. 

Longer Range: A slightly warmer storm off the Pacific ocean moves in Sunday afternoon for another round of snow to start. A transition over to rain is expected, but the timing of that is unknown right now. This Sunday storm could bring an additional accumulation before we thaw out. A warm up is expected Monday through Tuesday with rain at times, but then snow is expected back in the mix by Wednesday next week.

As always when arctic air is involved in our region the forecasts can change a lot from day to day. I am planning to just take this a couple of days at a time and provide updates here when we have changes.

For current weather conditions visit www.shorelineweather.com