Windy Conditions, Heavy Mountain Snow Expected Thursday and Friday

Wednesday was a dry and cool day around Western Washington. Some areas experienced dense fog and freezing temperatures on Wednesday morning. 

Late on Tuesday, colder air and showers from a leftover Puget Sound Convergence Zone brought localized lowland snow to parts of the South Central Sound, with a dusting near the Sound and a couple inches in the Enumclaw area. An unexpected surprise!

Our next storm system moves in late Wednesday night into Thursday morning. This storm will bring gusty winds, impactful mountain snow, and heavy rain showers with a chance of thunderstorms at times.

The winds will be the biggest impact in the South Central Sound area. Take a look at the expected winds from 5 forecast models below. (Big numbers=sustained winds, small numbers=gusts, arrows=wind direction)

Expect winds to increase early Thursday morning, continuing through Friday morning. Winds will be southwesterly, sustained 15-25 mph, with gusts 30-45 mph. Peak winds will likely occur late Thursday into early Friday. Forecasts suggest two periods of the strongest winds, Thursday morning and Thursday night/early Friday morning.

Tree damage and isolated power outages are possible.

Even stronger winds, gusting up to 50-60 mph, are possible in Whatcom County, the Admiralty Inlet area, and the eastern end of the Strait of Juan de Fuca.

The incoming storm will also produce bands of heavy snow over the mountain passes. Windy conditions will also bring the hazard of blowing snow. The forecast below from NWS Seattle shows expected snow from Wednesday night to Friday night.

The snow level will be around 2,000 feet, combined with heavy snow bands, to bring 2-3 feet of snow to the passes, and nearly 6 feet (WOW!) to Paradise on Mt. Rainier.

Be prepared for dangerous winter driving conditions if you will be traveling on the mountain passes from Thursday through Saturday.

Finally, the rain. Due to generally westerly flow, the Puget Sound area will be in the rain shadow with this storm, as seen in the UW forecast model below, showing precipitation through 4 PM Friday.

Expect 0.08-0.32 inches of rain through Friday morning. Wind will impact the South Central Sound more than rain. The most rain will fall north and south of Puget Sound and on the west slopes of the Olympics.