Warm East Wind Returns, Without The Fire Smoke

September 26, 2017

7:30pm Tuesday

Today was a spectacular early Fall day with high temps right around 80 in the metro area

It was the warmest day in about a week and a half

Tomorrow will be much warmer since we’ll go from a northerly flow today to a pure easterly wind flow

This means a big jump in temps, not only here in the valleys but also along the coastline.  Models are forecasting a 3-4 millibar pressure gradient across the Cascades which should give us gusts 35-45 mph in the western Gorge.  That east wind at the beaches (for just one day!) should push temperatures up into the 78-88 degree range

A wind switch back to west or southwest Thursday drops temperatures 15-20 degrees that day.

Here in the metro area temperatures should rise a solid 4-6 degrees tomorrow plus another degree or two Thursday.  Of course that puts us in the mid-upper 80s.  I think it’s unlikely we hit 90 at PDX; it’s more likely that at least one of the official metro area stations hits 90 one of those days.  It’s always a tough call at the end of the warm season due to lingering overnight inversions.  Regardless, it’s going to be quite warm for a few hours each of the next two afternoons.

As for fire smoke, I took a close look at the high-res GOES-16 visible imagery and couldn’t find any smoke being put out by any fire in our region.  That said, the view is from 23,000 miles out in space and most likely there are smoldering spots with each fire.  This morning I smelled fire smoke at my home but skies/air remained clear otherwise.   As a result I think we’ll at least smell a bit of smoke in parts of the metro area tomorrow, but that should be it.  No dense haze or smoke this time around.

Enjoy the warm & sunny weather because it’s pretty obvious we’re headed into another cool & wet pattern.  Friday and Saturday sure don’t look like soakers, but a wetter southwesterly flow Sunday and Monday should give us quite a soaking.  Here’s the ECMWF rain forecast through next Monday afternoon:

Notice in this pattern (southwest flow) more rain can make it over the Cascades.  You might finally get your first fall soaking in central Oregon if you get lucky! Looking farther ahead here is the 2 week outlook from the ECMWF model, showing 24 hour rain totals.  Time is from left to right.   Left is now, right is two weeks from now.    Top half of the graphic consists of 51 horizontal lines…each one representing one of the ensemble member 24hr rainfall forecasts.  You can see just about all of them start off with rain later Friday, then a 2nd peak in rain next Monday, and a 3rd sometime later next week.  Big picture is that there is no obvious dry period after Thursday, but there may be some sort of break the middle of next week.

Chief Meteorologist Mark Nelsen