3rd Heat Wave of Summer Has Arrived

August 5, 2018

10pm Sunday

The heat was back today…with the entire metro area reaching 90 degrees.

Todays Observed Highs OrWa 2017

The 92 at PDX marks the 21st time we’ve hit 90 this summer

90 Degree Days Summer Heat

Hot high pressure is pushing north through the Intermountain region this evening and that means hot weather sticks around the next few days.

Mark Why So Hot with Smoke

Tomorrow we should warm just slightly, but then a warmer atmosphere overhead Tuesday/Wednesday should push us well into the 90s.  Temperatures up around +22 to +24 at 850mb (around 5,000′) mean we could hit 100 in Portland.  But we don’t get offshore flow, plus another limiting factor for high temps is the thick layer of fire smoke this week.  It arrived this evening in Northwest Oregon and with the upper-level flow (see map above) out of the south/southeast through Thursday we should continue to see a sickly yellow sky obscured at times by even thicker smoke.

By the way, with the hot ridge centered right over Eastern Oregon, some areas in the Columbia Basin could approach 110 degrees Wednesday/Thursday.  Places like Hermiston, Boardman, & the Tri-Cities.

We won’t see any records this week because the big 1981 heat wave put those records up around 105!

Mark Hot Heatwave So Far

Try to stay cool this week; hopefully this will be the last heat wave with unusually warm nights.  It’s been great for the garden but miserable for those of you without air conditioning.

On the rain front…wow it’s dry!

Mark Dry Spells Summer Recent

Today was day #34 with no measurable rain at PDX.  That’s right in line with a typical summer dry spell, but of course the big story this year is the extremely dry late spring.  Very little rain in the past 3 1/2 months!  That’s very stressful on our trees/vegetation, especially since it happened 3 years ago as well.

Let’s hope for a (brief) late summer or early fall soaking!

Chief Meteorologist Mark Nelsen