Warmest in a Month Today

September 26, 2016

9pm Monday…

What a “scorcher” by late September standards…many of us in the western valleys hit 90 today; quite rare the 2nd half of the month.

Here in Portland the official high was 89 degrees:


Not quite a record, but close, and right on our forecast of 88-89 the past few days.  That always feels good.  Here are some other numbers around the west side of Oregon and Washington:


Models did very well with this one, both GFS and ECMWF kept pegging a high temperature in the western valleys around 90 degrees (or slightly below) for at least the last 4-5 days.  850mb temperatures peaked out at +22 over Salem this morning which was forecast as well.  Easterly flow was quite weak yesterday, but right on the 2-3 millibar forecast today.

Moving on, we have a nice marine push along with a weak cold front coming inland tonight.  That means a good 10-15 degree drop in high temps.  We’ll end up in the low-mid 70s.

The next 3 days look quite uneventful, then we go into a wetter pattern for the first week of October.  Take a look at the ECMWF ensemble rain forecast for the next 10 days:


Those green bars along the bottom show the ensemble average and the blue is the operational model.  Basically rain gradually accumulates starting sometime late Friday through at least the middle of next week.  The 18z GFS was similar with plenty of wet weather this weekend through early next week.  Snow levels will drop to around 5,000′ too so we may see at least a dusting of snow down to Timberline Lodge.

Finish up your outdoor projects by Friday morning!

Chief Meteorologist Mark Nelsen