Sunday, March 8, 2020

Western Washington is Not Done With Cold and Snow

Normally once we pass the first week of March, the lowlands are done with cold and snow.

But not this year-- at least if the latest model forecasts are correct.

Even this morning, unusually cold air aloft has brought some showers that produced some mixed rain and snow down to a few hundred feet, with snow reports from Clearview and Glacier, WA (click on link to view)


The freezing level was roughly 1200 ft this morning, with the snow level about 1000 ft below.   With a strong spring sun, the ground is heating up, producing a large change in temperature with height, and thus an unstable atmosphere with towering cumulus clouds and showers. And some of these showers have ice pellets and few snow flakes.

But the real potential action is late Friday and Saturday.  The latest UW high resolution forecast for Saturday morning at 8 AM is startling cold for mid-March, with the blue blue and purple colors in the forecast map below indicating a lower atmosphere cold enough for snow.   Having air this cold moving into eastern Washington is of great concern for agricultural interests there.

The solid lines in the forecast map are sea level pressure, indicating a low center off of northern Oregon.  A bit further north(by about 100 miles) and Seattle would have a major snow event.

The upper level forecast (the 500 hPa..about 18,000 ft) is shown below, with a sharp trough approaching the Northwest on Friday at 11 AM.  Close enough to the classic Seattle snow configuration to worry.


The cumulative snowfall forecast for the 24-h snowfall ending 5 PM Saturday (see below) has light snow from Seattle to Olympia and plenty over eastern Washington.  This is total snowfall, NOT ACCUMULATION.  There will be lots of melting this time of the year.


What about the European Center forecast for the same period (see below)?  Very similar with light snow reaching the lowlands.

Let me be clear, there is no big snowstorm to worry about, but we will see unusually cool temperatures during the next week.  Don't put out your tomatoes yet!😁  Or don't run out to food store to purchase toilet paper, milk, and bread.

9 comments:

  1. Oh great....it snowed on friends in Forks yesterday and today in Kingston we has a brief bout of cold, very cold hail...

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  2. ok. so we had spring like weather in February, and now we might get wintery weather this March... the opposite of last year!

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  3. You can't trust the models this far out.They waffle on a daily basis;the GFS is notoriously bad.Remember,a week ago they were also calling for much colder weather for this past weekend that what actually occured.The NWS knows ( from bitter experience) not to make any snow call until 48 hours or less before the event.

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  4. Yesterday we had a few intense hail storms in the Cowichan Valley on south Vancouver Island.

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  5. The first fruit trees to bloom are usually apricots in April, but this year they're already blooming in the Lower Yakima Valley.

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  6. again port angeles with the snow they had a good snow year they got 2 plus feet on top of those maybe snow event 6 inches there lucky but they are next to the olympics soo it makes since

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  7. It was 26.4F in NW Bellingham this morning - the coldest day of the month so far and the coldest day since February 20.

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  8. Very cold on top of Mailbox Mt. yesterday, with fresh snow down to 3000 ft. And the surrounding mountains were very white. Winter isn't relaxing it's grip yet...

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  9. Well, there isn't any toilet paper at the store these days. It's a self-fulfilling prophecy.
    I saw a good coating of snow on a logging truck coming down from the highlands around Steven's pass this morning. My fruit trees are trying to bud out and I feel like I'm watching an unwary toddler trying to cross the street! No! Wait! AHHHHHHHHH!

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