Light Snow and Cold. Next Up: Thursday Morning Snow Potential

The forecast models did quite well during the past day, with the cold air and light snow moving in yesterday and this morning.

Yesterday light snow fell over the northeast Olympic Peninsula, with a band extending over northern Kitsap and Camano Island.   And this morning, very light snow fell over Puget Sound (see picture below).  A few flurries are now occurring, but those should end soon.


Bellevue, Courtesy of Dr. Peter Benda

The lows last night in the west ranged from the mid-20s around Bellingham to roughly 30F in western WA and Oregon away from the water.  Teens were prevalent in eastern WA, with some single digits into terrain.  But the coldest temperatures were in valleys of the uplands of eastern Oregon, where one station got to 1C.


The air is now cold enough to snow throughout the region, but precipitation is essentially over as the upper-level trough that provided uplift moves away.  

Winds coming out of the Fraser River valley were extraordinary last night, with gusts getting to 55 knots (63 mph) in Bellingham.  Take a look at the winds at 1 AM this morning....a strong, cold current of air was flowing out of the narrow Fraser River Gorge.  Wind chills near 0F.  

Today will be a cold, dry day with highs in the upper 30sF in the west and 20s east of the Cascade crest.  The sun is too strong now to stay uber-cold during the day.

But tonight, with the sun down and earth radiating to space in cloudless skies, the temperatures will plummet, with lows in the lower 20s in the west and single digits to around 10F in the Columbia Basin (see the forecast for 8 AM Wednesday below from the National Blend of Models).  I have already talked to the city of Seattle emergency management folks about opening shelters for the homeless.

Minimum Temperatures at 8AM Wednesday Produced by the NWS National Blend of Models (courtesy of WeatherBell).

But the threat of lowland snow is not over!  

A weak disturbance will move southward across the region early Thursday.  At this point, the models are predicting some light snow over northwest Washington, but little over central and southern Puget Sound (see snowfall prediction for the 24h period ending 4 PM Thursday). 

Why no snow over Puget Sound?   We will be in the rainshadow of the Olympics under northwesterly flow aloft. The folks in Sequim will be jealous!  

The forecast models did quite well during the past day Light Snow and Cold. Next Up: Thursday Morning Snow Potential

We need to watch this one carefully--small errors could move the snow area.

Temperatures should warm up to near normal by this weekend.   The models indicate this. 

 But there is an even more potent predictor of warming temperatures and spring, one that the false-spring folks at the Seattle Times should do a story on (see below).  The arrival of garden supplies at local supermarkets.  











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