The Main Act is About to Begin, But Lack of Radar Coverage is a Problem

As predicted, the second.....and probably more potent...line of thunderstorms is now moving northward near the Oregon/WA border.

 The latest visible satellite image (4:26 PM) shows several major, strong convective systems entering Washington State.  The one on the right has good radar coverage from the Pendleton, Oregon NWS radar, but the western one is in the well-known radar hole over the eastern slopes of the Cascades.


 The radar image at the same time (below), shows intense radar returns with the eastern storms (red colors), but the western systems have poor coverage so we don't know how strong they are.  Since they are heading for the Cascades and western WA, this is not good.

Over the past half hour, lightning sensors have shown massive lightning in these storms (see below, each strike is shown by an "X")

There are some strikingly strong winds with this line of thunderstorms, with some gusts reaching 60-70 mph! (see the max gusts over the past hour below)

Notable weather enthusiast, Dr. Peter Benda of Bellevue, went storm chasing in the Tri-Cities today, and the picture of the mammatus clouds beneath the anvil of the approaching storm is scary (see below)

 And is another shot from Dr. Benda as the storm got close. Beautiful.  And you can see heavy rain falling out of the cumulonimbus.

And if you want to experience some of the strong outflow winds from the storm, check out the video he sent:

And there was hail with some of the more intense storms.  Here is a video provided by Pam Hayes showing the squash bass sized hail that hit around Tumalo, Oregon (just northwest of Bend) around 2 PM:
These storms will sweep northward during the next few hours.  Expect severe weather in the Columbia Basin and we will see how much of the action will get over the Cascades.  At the very least, the west side will have plenty of rain and some lightning.  The latest NWS HRRR forecast for 7 PM shows strong storms moving towards Ellensburg and Wenatchee, with others heading in the direction of Spokane, with light to moderate rain over the westside.  Without good radar coverage east of the Cascade crest, we won't be about to document the details there.


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