Much Cooler Weekend Ahead, But Not Much Rain | FOX 12 Weather Blog – KPTV.com

Much Cooler Weekend Ahead, But Not Much Rain | FOX 12 Weather Blog  KPTV.com

11:00pm Thursday…

We’ve had a nice spell of summer weather lately. Today was the 5th warm and dry day in Portland

We’ve only seen rain one day out of the past nine.

I finally hooked up my drip irrigation system in the garden the past two days; it’s pretty clear the summer dry spell has begun and we’re into a stable temperature regime. No long period of cold/wet weather is in sight.

THE BIG PICTURE

  1. There won’t be much rain the next 10 days or so. Showers are likely Sunday and MAYBE a shower the middle of next week, but that’s about it. You should now be watering everything in your yard and garden.
  2. Temperatures cool over the weekend, then bounce back to around normal through next week. There is NO SIGN of a hot spell or heat wave in the next 10+ days. If you want to hit the river or lake with your boat, you won’t find roasting hot temperatures to go with it.

In case you are headed to the northern Oregon or southern Washington coastline this weekend:

Take a look at the morning ECMWF ensemble model forecast of 24 hour rainfall. Each horizontal line on the upper half of the chart represents one “member”. Basically the model is run 50 times at a lower resolution with slightly different initial conditions.

Most ensemble members produce light showers overhead Sunday as an upper-level trough passes. But notice only about half of those give us .10″ or more. Not exactly a soaker! Then there are hints of a shower possibly Tuesday or Wednesday but that’s about it; mainly dry the next 15 days. The GFS model is similar

The cool weather coming for Saturday and Sunday is due to a cool upper-level trough dropping south out of Canada. If it was January we’d be talking about low elevation snow and modified arctic air moving south. The center of that low moves over Eastern Oregon and Idaho and that’s where the much heavier rain will fall. That low lingers through Monday and Tuesday over there. A very unusual late June soaker is on the way for northeast Oregon (which has been plenty wet this year). ECMWF thinks 1-2″ by Tuesday afternoon!

The Canadian model (GEM) brings an inch of rain all the down into the Ochoco mountains by this time.

This general pattern (without much rain) continues the rest of next week and likely beyond the 4th of July. Notice the below average heights across the West next week

Then just a bit below average heights for the 2nd week of July. This is from last night’s run of the ECMWF, but the GFS and GEM models are similar.

That’s it for this evening…I’ll be back at work Sunday.