Warm Spring Evening

April 30, 2009

Snapshot I'm getting old because I can still clearly remember the day we hit 90 degrees here in Portland 11 years ago.  A gusty east wind was blowing in the Gorge and it had been a bit hazy as well.  I could have the date wrong, but I also think this was the warm spell where we had a ton of Chinese dust in the air…the stuff that crosses the Pacific occasionally in the spring time and ends up here.  We had several days of extremely hazy conditions with no apparent source and a dry east wind blowing.

We sure didn't get much (hardly any) easterly flow during the daytime today, but still made it to 68 degrees.  But I see offshore gradients are picking up now and several spots have light east wind blowing, including here at the station in NW Beaverton.  We often get some easterly wind down off the West Hills in patterns like this.  The dewpoint is down around freezing as well.

IF we were to have solid sunshine tomorrow, the big chart we use shows a high temp in the mid 70s.  Instead, all models insist thick high cloud cover moves in soon after sunrise and lingers most of the day.  The first wave of an approaching upper-level trough just brings a few sprinkles to southern Oregon, but then the 2nd wave should give us some very light showers by daybreak Saturday.  The main surge of moisture this weekend looks like late Saturday and very early Sunday.  There may even be a break during the day on Sunday and possibly for the first part of Monday.  But then a wet westerly flow is still on for early next week…Mark Nelsen