There is a significant chance of several thunderstorms tomorrow (Thursday) over eastern Washington, eastern Oregon, and northern Idaho, with the potential for heavy rain, lots of lightning, and strong winds.
The Spokane National Weather Service office has a severe thunderstorm warning out:
The predicted strong thunderstorms will move in during the afternoon. The National Weather Service high-resolution HRRR model shows an intense line of thunderstorms (convection) moving through around 10 PM Thursday.
The line of thunderstorms will be associated with very strong winds in eastern Washington, with some gusts exceeding 60 mph (see wind gust forecast at PM tomorrow, below). I suspect the wind farms will be "feathered" to reduce damage.
Heavy precipitation will also fall, with the HRRR model going for huge totals over the Oregon Cascades. Substantial rainfall (over a half inch) over the Yakima River drainage.
The UW forecast model is also producing heavy rain over eastern Washington, which should be a great relief to those concerned about drought.
Why the potential for such an intense event?
The "set-up" is illustrated in the upper-level map below (for 500 hPa pressure, about 18,000 ft).
An upper-level trough of low pressure is approaching (yellow arrow), producing uplift that can release atmospheric instability. A second trough to the south (red arrow) is moving moist, unstable air in from the southwest northward into our region. Upslope on the eastern slopes of the Cascades will contribute additional meteorological fuel.
In short, later tomorrow will be an exciting time from the Cascades and to the east.
There are a LOT of moving parts with this one. Minor differences in timing these shortwaves or in actual surface dewpoints could make a real mess of things. I’m about to head to the east side with my camera, and I don’t see enough consistency in the models to trust any of them for position and timing. I’ll probably just keep a close eye on reporting station data, radar and satellite imagery, and use the interstates to stay mobile.
ReplyDeleteIf the UW model radar imagery and lightning forecasts DO end up verifying, or even getting close, I’ll be mighty impressed!
I’m in Spokane, and I can’t wait!
ReplyDeleteHaving grown up in the Midwest, I loved when thunderstorms would roll through.
My brothers and I got caught in our “fort” out in the woods one summer day when a storm dropped golf-ball sized hail on us.
Good thing the roof was in place!😂
They’re predicting possible 1.5” hail with this one.
I don’t think my garden would love that. 🙂
I am rooting for some action here on the West side too.
ReplyDeleteWow, that forecast was right on. Looks more like a Southeast storm than a Northwest.one
ReplyDeleteSo today in Western Washington, we have a slight smattering of misty rain....to be followed tomorrow by warming, sunny weather. Virtually no torrential, Spring rain has shown up so far this year...and no thunder/lightning storms....bizarre weather...but our more dry Eastern Washington, is going get drenched?
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