Bitter cold sweeps through Western Wash., snow less likely

The coldest weather of the season is about to formally get underway. Colder air from the interior of western Canada has begun to spill out of the Fraser River Canyon into the north interior. This surge of colder air will work its way south through the rest of Western Washington through the day today and tonight.

This push of colder air will mix with present moisture and generate showers, starting first as rain and then changing to snow as temperatures fall through the day. North interior locations like Whatcom County and the San Juans will see this precipitation transition first. Locations further south like the northern Olympic Peninsula and into Snohomish County will experience this switch around midday.

Later this afternoon, rain showers from the Kitsap Peninsula across to King and Pierce counties will shift to snow showers. This process is expected to continue further south through the southwest interior this evening. Snow amounts should be light and vary from a dusting to perhaps a few inches in higher elevations. In the Cascades, another 4 to 8 inches of new snow is anticipated through tonight.

In Whatcom County, the outflow winds from the Fraser Canyon is expected to peak overnight tonight and Friday morning with speeds topping out at close to 30 mph with gusts to 45 mph. Wind chills will drop well below zero.

Chris Sullivan: How to drive in the cold and snow

On Friday, a deep freeze will be in place with the colder air blanketing the region. High temperatures will struggle to reach the freezing mark and lows will fall down into the teens and 20s. Some wind-sheltered locations could have temperatures plunge into the single digits.

Earlier, it appeared the next opportunity for lowland snow would be Friday night and Saturday. Now, that incoming Pacific weather system appears to be more on track to head further south into Oregon and just the southwest interior has the best chance of light snow. If traveling to Portland and beyond, be prepared for winter driving conditions.

Otherwise, the rest of Western Washington will likely see some sunshine with more sub-freezing temperatures through the holiday weekend. By early next week, temperatures are anticipated to slowly moderate.

With the coldest weather of the season here, now is the time to prepare. At home, ensure water pipes are insulated indoors and out, and have plenty of food, water, and other provisions on hand. And remember, pets need preparedness too!

If you need to be on the road, be prepared for icy slippery conditions. Ensure your tires have good tread, carry items like a snow shovel and kitty litter for added traction, and have chains on board – it is state law.

Ted Buehner is the KIRO Newsradio meteorologist. You can read more of Ted’s stories here and follow him on X, formerly known as Twitter.