Weekend Storm Bringing Heavy Mountain Snow and Gusty Winds

FastCast—Saturday, Nov. 26 to Monday, Nov. 28:

The next storm arrives on Saturday evening, bringing heavy mountain snow, lowland rain, and area-wide gusty winds. With the Apple Cup late on Saturday and the post-Thanksgiving travel, impacts on the passes are expected. The passes will receive 10-24 inches of snow (higher amounts possible) from Saturday night through Sunday night. The heaviest snow will fall on Sunday. In the lowlands, the main impact will be gusty winds from late Saturday evening to early Sunday morning. Peak gusts around the region will be 30-40 mph, except up to 45-50 mph from Port Angeles to Everett, including Whidbey Island due to a westerly wind surge. The lowlands will pick up 0.25-0.5 inches of rain, and the coast will receive 0.5-1.25 inches. Temperatures will be slowly falling throughout Sunday and Monday. This will make it possible for localized areas in the lowlands to see some snow accumulations on Monday morning in Convergence Zone bands. However, this is very uncertain, so stay tuned for the Sunday evening blog for more information. For Saturday to Monday, expect highs in the upper 40s, cooling to the low 40s, and lows in the upper 30s, cooling to the low 30s. Stay tuned!

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Continue reading the full blog below!

An impactful storm is ahead this weekend, with the biggest impacts being heavy mountain snow and gusty winds. Let’s take a look at the forecast. 

Below is the NAM forecast for snow through 11 PM Sunday. Most snow at the passes will fall from Saturday night onward.

This forecast shows a total of 18-36 inches at the passes by late Sunday. 

As always, no forecast is truly accurate unless it agrees with other forecasts. The European model forecast for snow through Sunday night is below.

The European model shows 12-24 inches for the passes. This is perhaps a bit more reasonable than the NAM prediction. However, either is possible. Regardless, the heaviest snowfall rates will be from early Sunday morning through the night, with only brief breaks possible around midday. 

Travelers need to be prepared for winter storm conditions over the passes on  Saturday night and all day Sunday. This is especially important with the influx of traffic due to post-Thanksgiving travel and the Apple Cup.

In addition to heavy mountain snow, there will be gusty winds across the region this weekend. Peak winds for the lowlands are expected from late Saturday evening through early Sunday morning.

Below is the European model forecast, showing peak winds overnight from Saturday to Sunday.

The European model forecast shows peak winds of 35-40 mph for the Central Sound, with higher gusts up to 45-50 mph for areas from Port Angeles to Everett due to a westerly wind surge. Eastern Washington and the coast will gust 40-45 mph. 

A higher-resolution forecast (NAM) is shown below, showing peak winds in the lowlands. 

The NAM shows peak winds in the lowlands around 11 PM Saturday, with gusts of 35-45 mph from Tacoma northward. The westerly wind surge (45-50 mph gusts from Port Angeles to Everett) will occur early Sunday morning.

Gusts of 30-45 mph are enough to cause isolated tree damage and power outages, so be prepared.

There will be some rain with this system as well, but much less than Friday’s storm. The rain forecast through 11 PM Sunday from the NAM model is below.

Expect 0.25-0.5 inches in the lowlands and 0.5-1.25 inches on the coast. Note that the high rain amounts in the mountains will fall as snow.

Stay tuned for my next blog post on Sunday evening with an update on the upcoming arctic outbreak in the Pacific Northwest.