Disruptive Winter Storm Thursday/Friday

 It has been an impressive stretch of cold (and snowy) weather so far! Temperatures for the first 11 days of February have been solidly below average and will continue to be so for the next couple of days. But all good (or bad) things have to come to an end and so will this pattern. However, before that we have more wintry weather to go through.

Temperatures will once again get very cold tonight, and we have cold weather advisories in place for that threat.

Skies will be clear once again tomorrow, which will make for a nice, clear day, albeit a bit chilly.

Then tomorrow evening, a system begins spreading precipitation into Oregon. With cold temperatures in place, most of this will start of as snow, but this system will scour out the the upper level cold quickly and this should transition to freezing rain and sleet for the Eugene to Salem area. 

Moisture continues to move north on Thursday, entering the Portland area around 9 AM. Temperatures will be plenty cold for snow in Portland, but once again the upper levels will warm, so I expect a transition to freezing rain/sleet, especially for areas south of Portland. In the immediate Portland area, precipitation may stay snow for longer since the low is pulling cold east winds out of the Colombia gorge. It is uncertain where the line between freezing rain and snow will be, but there is a chance precipitation type stays snow for the whole day in Portland as the low meanders off the coast. The dynamics remind me a bit of Feb 2023 and this will likely be a disruptive event for them.

Precipitation moves into the Puget Sound Thursday evening. Temperatures look a bit more borderline in Western Washington but it should be snow, especially in the South Sound, where precipitation amounts look to be higher. The precipitation will also be fighting very dry air, so although returns may look impressive on radar, not a lot may make it to the ground initially. However, the ground should be plenty cold for accumulating snow so anything that falls will stick. 


Then, as the low continues to move east, Western Washington could see some additional snow on Friday with a deformation band. There is a bit of uncertainty as to where the most snow will fall with this, but most of Western Washington should see some snow. Amounts look to be on the light side, but there are usually some surprises with these bands.

Overall I think the European model looks to be the most reasonable with amounts for this event.


A widespread 3-4 inches in the Portland metro, similar amounts south of Olympia (this model is underdoing those totals), and 1-3 inches of snow for most of the Puget Sound. 

Also expect some ice in the Willamette valley, maybe even some for Portland but the latest EURO run keeps it all snow. Will have to watch for that. Will be a messy Thursday/Friday down there.



Stay safe and have a good night!!


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