September 13, 2026

A "Perfect" Storm Hits the Northwest

If you were to order a "storm" for the Northwest, you would request one that drops lots of rain over the crest and eastern side of the Cascades, decisively ending the wildfire season and providing needed moisture to late-season crops.

To do so would require an upper-level low centered along the northern Oregon or southern Washington coast, which would swing moisture in from south into eastern Oregon and Washington.  

Exactly what is happening this weekend (see upper-level map for 2 PM Saturday).

Upper-level chart (500 hPa pressure level) for 2 PM Saturday. 

The resulting clouds swirling around the low are impressive:


As was the radar image last night.


Consider the  "storm" precipitation totals as of this morning around 6 AM (below).

Nearly an inch at some locations east of the Cascade crest as moist air swung around the low and rose on the eastern slope.


Looking forward, the total precipitation predicted through 5 AM Monday (by the UW WRF model) is quite impressive, with several inches forecast east of the Cascades, exactly where we need it to end the fire season


And believe it or not, it is cold enough aloft to result in some snow at higher elevations (see below)


We will have a warm/dry period this week, followed by the return to much heavier precipitation in ten days.  Welcome to autumn.




13 comments:

  1. Thank you. Is the total precipitation predicted by the UW WRF model graphic publicly accessible? I looked at the Modeling tab but didn't get that graphic.

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  2. We picked up 1.15 in. of rain over the weekend here in Yakima.

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    Replies
    1. That is very impressive for this time of the year!

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  3. Good rains fell on the Little Giant fire which should help take care of that fire but much less fell on The Sisi fire northwest of Stehekin, probably less than a quarter of an inch, so it will probably take another good storm to take care of that area.

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    Replies
    1. At least these horrific blazes don't seem to be spreading any further. They have scorched more than enough acres.

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  4. The Trump administration plans to announce Monday that the United States will no longer limit the planet-warming pollution that power plants pump into the air while burning coal and gas, according to two people familiar with the proposal. See what you voted for? How about some more 'folk wisdom' on doing this?

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    Replies
    1. I certainly didn't. I don't see how any thinking person could vote for him.

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    2. I guess we will be having more problems with air quality going forward. Such a shame.

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  5. I got 0.51 inches of rain on the Bothell-Mill Creek line during the Sunday wee hours. Better than anything since June.

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  6. Good news. Mt. Rainier fires appear to be out but it looks like most of the other fires further east are still burning

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  7. The past few days have been strangely hazy. Accuweather has even shown poor air quality readings. I can't really tell if it's wildfire smoke or pollution getting trapped in a stagnant weather pattern. We've been cloudy, a little wet, and breezy at times. I'd normally associate clouds with a marine push, but perhaps these clouds are coming from the E/SE and bringing smoke along with them.

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  8. Total WA wildfire acreage for the year has now surpassed 900000 - second only to 2015 and nearly 100000 acres more than the previous second place holder, 2020.

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  9. The 36hr UW WRF model really nailed the heavy precip over the Cascades on September13-14, especially over the eastern slopes, even the snowfall over the Enchantments. Had that unprepared Oklahoma couple visited the Enchantments at any other time this month, even without a tent or overnight gear, they likely would have been okay.

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