Active Weather Returns To the Pacific Northwest

November 2022 started out with a bang. A very strong, westerly atmospheric river came through the area on Friday, November 4, resulting in extreme rainshadowing for the Seattle area but widespread flooding over the Washington Cascades. And entering the second week of November, some forecasts were calling for an early-season shot of lowland snow. The weather groups were buzzing with analysis of the latest model runs and lowland snow prognostications, and the excitement was palpable. Though I believed the lowland snow chances were a little far-fetched, I was looking forward to an early start to ski season and potentially having Snoqualmie Pass open for Thanksgiving skiing for the first time since 2011.

But Mother Nature had other plans. From November 8-21, Seattle received no measurable precipitation, making it the longest stretch of dry November days in Seattle’s history. The weather groups have gone crickets, like Lumen Field after a Seahawks fumble. While Buffalo saw record-breaking lake effect snows, much of the Inland Northwest was under a dreaded “air stagnation warning” due to a ridge of high pressure overhead and the development of an inversion over the Columbia Basin. About the only “exciting” weather for the Pacific Northwest was the gusty east winds at Crown Point in the Western Columbia Gorge, but as a bike rider with 5 years of experience living in the Portland metropolitan area, those cold, winter east winds tend to lose their novelty pretty quickly!

Thankfully, the rain finally returned to the Pacific Northwest on Tuesday. Today has been rather gloomy, and the sunshine should make one last appearance on Turkey Day before a more persistent cool, wet pattern sets up on Friday. Though we didn’t get any Turkey Turns up at Snoqualmie Pass this year, we’ll likely have some ‘Christmas Carves’ a month from now.

Thanksgiving Forecast

Thanksgiving will be a stunner. After some light morning fog in spots, Western Washington and the Willamette Valley should rise into low-mid 50s under mostly sunny skies. But temperatures will be even warmer 1000-2000 feet above the sea-level inversion, with highs potentially reaching the 60s over exposed, sunny mountain ridges. It should be a wonderful day for a hike up to Poo Poo Point on Tiger Mountain, Neakahnie Mountain on the Oregon Coast, or even Paradise Ranger Station up on Mt. Rainier, where temperatures should still make it into the 40s even at 5,400 feet.

The below graphic shows the temperatures at 925 millibars (approximately 2,500 feet) at 2pm tomorrow. Orange = temps in the 60s. Note the cold, dense air bottled up east of the Cascades.

Here’s another view, showing the temperature forecast at 850 millibars (approximately 5,000 feet). The temperature rises all the way to 10^o C (50^o F) before crashing back down with the arrival of a cold front on Friday.

Friday’s cold front will be the first in a series of cool, wet systems arriving from the NW into the Pacific Northwest. None of these systems will be particularly strong, but they will result in steadily accumulating snow over the Cascades with snow levels down to 1,500 feet.

Things become a little more interesting as we head into the first week of December. Models show the flow trending from northwesterly to northerly, and although this will result in decreasing precipitation, it will result in colder temperatures – and potentially some chances for lowland snow. There’s still quite a bit of variance in model solutions and it’s too early to make any specific lowland snow forecasts, but it’s something worth keeping an eye on.

In the meantime, enjoy the beautiful weather this Thanksgiving and more consistent snow beginning in the mountains this Friday!