How Hot? : Version 2

July 18, 2006

So here we go with "how hot" talk again.

First, looks like last night’s marine push has pushed itself out since onshore gradients are much weaker this evening.  Probably no low clouds inland in the morning…that will be the last cloud cover we see until at least next Tuesday.

So you may have noticed I raised Friday 2 degrees, dropped Saturday 1, and Sunday 5.  All models have really come together on the large scale details from Friday-Sunday now, so we get to argue (I know you folks do) over the small details. 
I’ve noticed the trend over the last 24 hours of models is a slightly weaker upper-level high, and much more significant…it’s over or slightly east of us Saturday-Sunday.  The 1981 & 1965 heat waves that gave us 105+ had the upper level ridge slightly west of the coastline, which drags the thermal trough west to the Coast too.  In our forecast weekend pattern it doesn’t give us as sharp of a thermal trough west of the Cascades and saves the Coast from extreme heat too.  I REALLY doubt we’ll see 105 at PDX in this pattern.  Plus onshore flow late Saturday & Sunday should be enough to drop us into the 90’s Sunday, but I left the 100 on for Sunday for now.  I may drop it tomorrow, or the Drew/Andy forecasting duo may do that in the morning.
So as I mentioned at 10pm, it looks like a really good heat wave, comparable to 1994, but not 1981.  We would need the ridge to stick around through Tuesday for that.   Okay boys and girls, discuss in detail…Mark