Snow warning for far North Sound; Puget Sound chances waning

Snow warning for far North Sound; Puget Sound chances waning
Saturday night snow in Anacortes (Photo: Stephanie Hathaway)
SEATTLE -- As we watch a brewing battle between cold and warm air over Western Washington, latest indications Saturday evening are the warm air may be getting the upper hand.

The result? A lower chance of snow across much of the Puget Sound region, although snow is still likely in parts of Western Washington -- namely the parts that are fairly close to Canada.

Some snow is already here in Bellingham and its nearby cities like Ferndale and Lynden. A Winter Storm Warning is in effect there for as much as 1-3 inches Saturday night, then another 1-3 inches Sunday and a final 1-3 inches Sunday night for a storm total of 3-7 inches.

But really, as we have been saying, that is the one place that was a good bet for snow, aided by some cold air trickling out of the Fraser River Valley.

A Winter Storm Watch remains in effect for areas that have been under the watch for much of Saturday -- that would be from essentially the King/Snohomish County line north to the Canadian border (including Lynnwood, Everett, Marysville, and Mt. Vernon (remember Bellingham/Whatcom Co. already have a warning), the Hood Canal area, the north Sound Islands (San Juans, Camano, Whidbey) the northern Olympic Peninsula (Pt. Angeles, Sequim) and the North Coast (Forks). .

A "Watch" means there is potential, but not yet assured and latest forecast guidance from Saturday evening are reducing the threat further. But while there is a waning chance, there is still a chance for 2-5 inches as an overall total by Sunday night, so the watch remains but with a big asterisk.

Those left out of the watch area, which includes the Seattle/Bellevue and Tacoma Metro areas (and now the King/Pierce County foothills), as well as all points south are likely to remain too warm for heavy snows although areas may at least see some snow at times, with maybe 1" in the Seattle area hilltops and the Cascade foothills north of I-90.

It remains a very tricky forecast as while moisture is present, there is still a challenge of deciphering how much cold air will be present to make it snow and how far south it will spread.

The cold air is dependent on arctic air that is building in the interior of British Columbia being drawn into Western Washington through the Fraser River Valley near Bellingham.

The BIG question remains: How far does that cold air spread across Western Washington? There will be a distinct rain/snow line in our region this weekend, the challenge will be where it sets up, as obviously 30 miles either side of this line could have wildly different weather, with potential major impacts to those on the north side and major disappointment for those on the south side.

But even the forecast model that had been advertising the rain/snow line would be far enough south to bring snow to Seattle has backed off, now joining others that have been consistent in keeping that rain/snow line around Mt. Vernon and areas south in the rain or mix or slushy snow. The models do still suggest the northern Olympic Peninsula will get some accumulating snow as well.

The Winter Storm Watch remains in effect to cover for potential for those areas being on the snow-side of the line, but especially as you head to the southern fringe of that watch area, potential increases for getting little to no snow if the snow line remains further north. Also note that the northern Olympic Peninsula also have greater potential for snow due to proximity to the Olympic Mountains.

OK, we've tossed a lot at you, so let's recap:

Bellingham/Whatcom County area: Snow pretty much non-stop through Sunday night. A Winter Storm Warning in effect for 3-7 inches of snow. NE winds will also become gusty and make for a wind chill. Temperatures to remain near freezing through Sunday night, warming into Monday.

Skagit County/Clallam/ San Juan Counties: Snow is around tonight in Skagit and San Juan counties and will intensity by Sunday afternoon. Clallam County will see rain change to snow around midday Sunday. A Winter Storm Watch is in effect here for as much as 2-5 inches of snow by Sunday night -- for Skagit County, a sliding scale of north to south of heaviest to lightest accumulations.

Everett/Snohomish County: This is going to be close. It's looking more and more likely that Snohomish County will remain on the warm side and stay rain, but there are a lot of locales there that are around 500 feet and they are going to be fairly close to the cold air that a slight increase in the north wind could bring snow here. You're still in the Winter Storm Watch, but on the fringe. I'd say you're probably 40-60 snow-rain odds, but can really go either way. One scenario: You end up with a non-sticking snow like Saturday.

Seattle-Bellevue-Bremerton:Your already slim odds for snow just got slimmer with the last holdout forecast model that had snow that far south now backing off, joining the others. Likely just a cool, rainy day with maybe some wet snow on the higher hilltops that doesn't stick.

Cascade Foothills: Further north you go the better, but even there, maybe 1" with decent elevation. N. Bend/Issaquah likely too warm, but will be close.

Tacoma-Olympia-Southwestern Washington-Coast:: What snow? You got the bulk of the snow two weeks ago, you're likely just rain with highs in the low-mid 40s this time around.

Hood Canal area: Not looking like much snow here either -- you'll need a much stronger wind out of the Fraser River Valley to get snow and models are leaning toward not getting enough.

Snow/rain decreases Sunday night and we warm to where whatever showers are leftover Monday morning will be rain. It looks like Seattle, Bellevue and Tacoma's commute may be OK --perhaps Everett's too now, but points in the far north may have challenges.