Arctic Air Arrives: Snow Showers, Cold Temperatures, and Frigid Wind Chills

FastCast—Tuesday, Feb. 22 to Friday, Feb. 25:

In the wake of our weather systems this weekend, Arctic air has begun to move into Western Washington. Fraser outflow winds are gusting 40-60 mph in Whatcom County, bringing low humidity and frigid wind chills. Parts of Western Washington have received snow showers today, with the most significant accumulations near Stanwood and Camano Island (up to 8 inches). Other areas, particularly from North Bend to Federal Way, the Northern Olympic Peninsula, and areas between Everett and SeaTac have received snow too. These showers may continue through 1 AM Tuesday for areas west of the Sound. Dry air moves in as the showers end. Skies will clear by midday Tuesday, and temperatures will drop into the upper teens to mid 20s across Western Washington by Wednesday morning. Wind chills will make it feel like 5-20 degrees at times due to Fraser (N-NE) and Cascadia (easterly gap) winds, gusting 20-35 mph in the lowlands and up to 65 mph in Whatcom County. Expect highs in the mid 30s to near 40 and lows in the mid to upper 20s through Friday.

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Continue reading the full blog below!

As the Arctic boundary moved south into the lowlands, it produced some snow showers around the region. Snow accumulated up to 8 inches near Stanwood and Camano Island on Monday morning. North Bend got some significant accumulation (see WSDOT camera image below) and areas from Covington to Federal Way, between Everett and SeaTac, and the Northern Olympic Peninsula also received snow accumulations on non-road surfaces on Monday evening.

Snow accumulated enough to cover I-90! Some areas west of Puget Sound may receive snow showers through around 1 AM.

Meanwhile, in Whatcom and San Juan Counties, the Fraser outflow winds are roaring. Gusts have reached 60 mph in Bellingham and 50-55 mph on the San Juan Islands. The entire power grid for San Juan County has been knocked out, and wind chills are in the 10-15 degree range. (Peak gusts as of 10 PM Monday below)

These winds will continue gusting 40-60 mph through Tuesday afternoon. Wind chills of 5-15 degrees are expected in these areas.

In the Central Sound, E-NE gap winds are expected, gusting 20-35 mph, through early Wednesday. Gap wind conduits are clearly seen on the 8 PM Tuesday forecast from the NAM model.

Winds out of the Fraser River Valley, the Stampede Gap (between Seattle and Olympia), and the Columbia River Gorge (Portland) can be seen gusting up to 35 mph by Tuesday evening.

Below are wind chills at the same time (8 PM Tuesday).

With winds gusting 20-35 mph, wind chills of 10-20 degrees are expected in the lowlands. Winds gusting 40-50 mph are possible in East Central Washington, and Eastern Washington wind chills will reach a frigid -10 to 15 degrees.

Additionally, the air will be quite dry due to the prolonged offshore flow. Dewpoints on Wednesday morning are below. (Dewpoints are the temperatures where water droplets form).

Wow! Dewpoints in Western Washington will reach 0 to 5 degrees! Other forecasts agree, generally showing dewpoints of 0 to 10 degrees and relative humidity of 20-40%. You’ll notice how dry it is…expect your throat to be dry and your skin to be chapped. 

Temperatures will be quite cold for the second time this winter. Below is the NAM forecast for low temperatures on Wednesday morning.

Wednesday will be the coldest morning, with lows in the upper teens to low 20s in Western Washington and 5 to 15 degrees in Eastern Washington. 

Expect lows in the mid to upper 20s (colder in some spots) through Friday night in the lowlands. Highs will only reach the mid 30s to low 40s in the lowlands. Lows in the 5-15 degree range are expected in Eastern Washington through Friday night. 

 

Stay tuned for more information as the Arctic air and cold temperatures set in!