April 20, 2012


The latest model runs are in and it appears clear now that we have an extraordinary weekend ahead--with the only exception being the northwest WA coast.   The trend in model solutions suggest less concern for clouds reducing the highs on Sunday across the western interior.

The latest radar imagery (Friday 9:30 PM) indicates a few shower over SE Washington and that they are dissipating and moving out rapidly.

Tomorrow, as the ridge builds, temperatures will warm up considerably from the temperatures we experienced today: mid to upper 50s in the west and the upper 60s over the basin of eastern Washington.

Lets take a look what we expect.  First, lets start with the 4-km run of the UW WRF for 5 PM Saturday...near the time of max temperatures:

 Amazing.  Temperatures reach well into the 70s across the Willamette Valley and the basin of eastern Washington, and upper 60s extend as far north as Seattle.  Twenty four hours later, on Sunday afternoon, the temperatures surge upward, with upper 70s and lower 80s spreading across eastern Washington, the SW WA interior, and the Willamette Valley.  Even the Puget Sound region hits the lower 70s away from the water (see graphic)

Now this is of course, from a single model run.  Lets take a look at output from PROBCAST, which is based on statistically postprocessing an ensemble of forecasts.   PROBCAST is very good with warm temperature situations.  Below is Probcast's max temps for Saturday and Sunday.  Very similar idea to the WRF runs.

 Now the only reason to get nervous about this forecast is that there will be some clouds along the coast that will stretch into southern B.C.  Here is the cloud forecast from WRF for 5 PM Sunday:
You see what I mean--coastal cloud that extend into BC....and here is the probability of precipitation on Sunday from Probcast.  It looks like nearly all of WA, except for the far NW coast is safe.  Don't go up Vancouver Island or north of Vancouver---it looks wet there.  Personally, I plan to experience some real heat and mountain bike around the Ancient Lakes area near Quincy.  Enjoy the weekend....this is surely not like last spring.

PS:  the Lyrid Meteor Shower is this weekend...if you get up before dawn on Saturday or Sunday, take a look...

1 comment:

  1. Very warm here today in Walla Walla, WA, and right now I'm watching a major storm pass overhead--thunder, lightning, wind gusts, hard rain....very exciting.


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