Wednesday, July 28, 2010

Thunderstorms and Rain to the East

Thunderstorms and heavy rain have hit the eastern slopes of the Cascades and portions of eastern Washington and Oregon, with a little spill-over over the upper slopes of western WA.
Take a look at the radar imagery tonight around 7:15 PM from the Spokane and Portland radars (see below). Lots of echos east of the crest with very heavy rainfall over the eastern slopes near Wenatchee and Leavenworth.


The showers were so intense near Wenatchee that there was localized flooding and mudslides. Here are a few pictures courtesy of the Wenatchee World newspaper:


According to the Washington State DO, US 97 A, milepost 220 to 222, is closed over night due to heavy rain fall, mud and debris over the roadway.

Why the thunderstorms? The air east of the Cascades has been relatively unstable and a weak upper level trough (see below) has been moving through the east side, providing enough lift to release the instability (producing thunderstorms). The lightning detection network indicates hundreds of lightning strikes. This is not a good thing since they have the potential to initiate wildfires. In fact, one such lightning-produced fire was reported near Yakima.

More thunderstorms are expected east of the Cascade crest the next few days...so if you want rain you know where to go!

1 comment:

smokejumper said...

There was a flash flood warning issued for my zone today here in NW Yakima county. Local 2.5 inches of rain.

Because of my poor skills, my dad got around 50 acres of cut hay destoyed. My gauge picked up a tenth, but only 1000m down the road, I estimate it rained well over an inch. It was a tangible wall of water for 30 minutes.

Our dry creek bed is running muddy water tonight. That confirms flooding occurred further up the sage hills.

About 1/100th of the Heppner flood you wrote about in your book. I did not know about, simply amazing. People check it out.