Summer Heat

Depending on your preferred weather app, you’ve probably seen something like this forecast for the next 10 days in Spokane from Accuweather:

Yes, summer heat has arrived.  The last two weeks of July and the first two weeks of August are on average the peak of the summer heat season.  Here’s the current weather map:

The dominant weather feature is a large high pressure center over the central US.  It set all-time records in eastern Montana on Sunday including 115F at Miles City.  

The high is just a little too far east to bring triple digits to the Northwest. But there’s also a small low just off the Washington coast.

We talked in the last blog about monsoon moisture paying a visit to our area this week.  For the most part this will be mountain thunderstorms.  Tuesday afternoon could see some storms over northeast Washington mountains.  But that small low is forecasted to move across northwest Washington mid-week, and when it does, that will be our best chance of rain in the lower elevations.  Still, it only a small chance  of rain in the Wednesday night through Thursday night time frame.  Here’s the probability of rain from the European model.

Dew formation will be tricky to predict this week.  Our dew points will rise to around 50, and our low temperatures should drop into at least the upper 50s, which should mean at least a light dew for a few hours. But we could also see some clouds at night, which will keep our low temperatures in the 60s and inhibit dew formation.

From Thursday onward our temperatures will ratchet up a few degrees, into the mid and upper 90s.  A few 100s are possible.  These temperatures could persist through all of next week.  And the monsoon moisture supply continues for a renewed threat of thunderstorms next week.