Bizarre Clouds Seen Over Puget Sound, Plus My Latest Podcast/Forecast

 During the past day, I have received several emails and pictures of a strange cloud feature seen from roughly 4 PM to 5:30 PM on Thursday.  Let me show you.

Theresa Verway took this picture from Shilshoe Beach in Seattle around 4:12 PM 



Steve Moseley took this picture in N. Seattle around 5:18 PM



And here are two views from the Seattle PanoCan, one around 4 PM and the other around 5:30 PM.  Note the blue skies nearby....that will be important.




So what caused these strange clouds?    

To gain some insight, let's take a look at high-resolution satellite imagery at the same time.....that should provide some major hints!

Here is a high-resolution visible image at 4:30 PM.  For a trained meteorologist the imagery suggests a high-amplitude mountain wave forced by the Olympics.


Let me explain, using a marked-up version of the image below.  On Thursday, there were strong southwesterly winds (from the southwest) approaching the Olympics--see red arrow.  As the air rose on the western side of the Olympics, clouds (and precipitation) were enhanced.   

But as the air moved down the northeast side of the Olympics it descended, drying the air and producing a clear zone (see blue arrow).  

The movement of the air up and over the Olympics established a mountain wave pattern and the air subsequently rose rapidly downstream, forcing an impressive area of clouds (green arrow).  


This high-amplitude mountain wave pattern can be simulated by our best forecast models, such as the UW WRF modeling system.  In fact, our model predicted this interesting cloud (see below)



Such high-resolution mountain wave clouds can have very complex structures in three dimensions, and that was certainly the case on Thursday afternoon.  So complex that some folks have mistaken these clouds for UFOs--unidentified flying objects.



My podcast today will be about the interesting forecast for this week--lots of weather action and mountain snows ahead!.
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  I have received several emails and pictures of a strange cloud feature seen from roughly Bizarre Clouds Seen Over Puget Sound, Plus My Latest Podcast/Forecast  I have received several emails and pictures of a strange cloud feature seen from roughly Bizarre Clouds Seen Over Puget Sound, Plus My Latest Podcast/Forecast
Like the podcast? Support on Patreon 


I have received several emails and pictures of a strange cloud feature seen from roughly Bizarre Clouds Seen Over Puget Sound, Plus My Latest Podcast/Forecast







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