Strong Wind Gorge Now, Then This Afternoon In Valley

October 25, 2015

8am Sunday…

Looks like some real windy fall weather coming up today.  I’m not working, but with morning coffee I see two things going on:

  1.  Strongest east wind of the season so far is howling through the Gorge.  Over 8 millibars pressure gradient is “cold season worthy”.  It’s flowing from high pressure east of the Cascades to an approaching surface low off the central Oregon coastline.  Peak gusts likely 60-70 at Vista House and 50-60 in the windier areas around Cape Horn and Corbett through the morning hours.  Then it’ll go calm as a south wind arrives around noon or so.  Which leads us to…
  2. Gusty south wind for all of us this afternoon.  South wind gusts 25-40 mph will likely cause a few outages 3-7pm in the metro area and the valley.

A surface low is cozying up against the coast this morning and moves into western Washington this evening.  Note the mid-afternoon (2pm) surface map from the 12z NAM (latest model available).  You can see the pressure gradient turning southerly south of Salem at that time

slp.09.0000

Then at 7pm the low is weakening, but in a perfect position to cause a rush of southerly wind up (technically down) the valley

slp.14.0000

Not a big windstorm by any means, but enough to remind us November is only a week away!  In fact I noticed the cross section from the WRF-GFS last night has that “winter look”.

kpdx.th

By that I mean strong easterly flow, then southerly flow, then back to strong easterly again Tuesday.  My son has his last high school soccer game in Corbett Tuesday afternoon…looks like that ball is going to have a hard time getting into the goal when they are kicking into the east end!

Rain will be arriving for most of us soon, enjoy that and the refreshing fall breezes this afternoon.  Oh, and possibly a thunderstorm with the convective showers mid-late afternoon as well.

Chief Meteorologist Mark Nelsen