June 03, 2020

The Highest Cloud Tops in Many Years for Western Washington


Online Talk:  The Mathematics of Weather Prediction, Sunday, June 7 at 1 PM.

I will be giving a talk on the how mathematics is used in weather prediction that will be available online (Zoom).  This is part of the "Math Hour" outreach of the UW Department of Mathematics and is directed to middle and high school students, but should be interesting and accessible to a wide audience.  If you are interested, you should register here.  If the 1 PM session fills, will do it again at 2 PM.

On Saturday morning, as thunder rumbled through the region, something remarkable happened:  radar and satellite imagery revealed the highest thunderstorm tops I have ever seen west of the Cascade crest, with some extending to 49, 000 ft.

These were the tops of active thunderstorms, in an area where we get excited if they get to 25,000 ft.

We can determine the thunderstorm tops using the local National Weather Service weather radars, which provide echo tops:  the highest elevation in which the radars are seeing precipitation.  Clouds without precipitation could extended even higher!

The echo-top plot at 6:38 AM Saturday (1338 UTC) from the Camano Island radar shows a cell reaching 49,000 ft not far from Mt. St. Helens.  Unbelievable.

And such huge thunderstorms during that period were confirmed by the Portland radar. Here is the Portland radar image at 7:32 AM....only 47,000 ft.

These heights were confirmed by the Langley Hill radar near Hoquiam.

The visible satellite imagery at the time (6:41 AM) shows a number of large thunderstorm cells, with one in question to the northeast of Portland.

Zooming in, you can see the shadow of the very high thunderstorm core (known as an overshooting top in the weather biz), surrounded by a huge anvil area.

That super thunderstorm cell has plenty of "juice", with lots of lightning.  Here are the lightning strikes for the 30 minutes ending 7:30 AM.  Many dozens.

The Saturday morning even was associated with a very favorable set up, with a sharp upper  trough approaching, substantial mid-level instability, and an unusually warm/moist air mass.


  1. Any chance of photographs of the high tops from pilots? (I know there are few flights now...)

  2. I wonder how those heights compare to somewhere like Kansas

  3. But we still have not seen serious thunderstorms in Western Washington this year, so far...just wimpy ones!...Bring it on, Thor!

  4. I enjoyed some grape sized hail courtesy of one of those.

  5. I was watching a radar recording of those overshooting tops when they were in central WA...billowing like a frothing pot! Ultra cool!!!

  6. Average thunderstorm heights in the Midwest are 35,000 ft - 45,000 ft, however, severe thunderstorms can get to heights of 60,000 ft - 65,000 ft.

    1. True that is. These even the airlines cannot fly over. They must be flown around.

  7. So cool! So impressive how you can study clouds six ways to Sunday. This is information I can spout off to friends and family like a weather know-it-all!

  8. The new 500 meter satellite images are awesome. Love learning how to interpret them. Thanks for pointing out something new here!

  9. Evening storms approaching our little town in SE Wisconsin from the west would create the silhouette of towering alpine peaks. My dad and I used to go for walks and watch these 'mountains of the Midwest' slowly change shape, knowing that in 2-3 hours all Hell would break loose around us. Amazing 'engines' for transporting heat!

  10. Makes for a bumpy and nerve-racking plane ride!

  11. Cliff,

    Extreme thunderstorms are exciting and comforting for me. I really had a good time with them. Thanks for the education about them in Washington.


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