Nothing But Sunshine In The Forecast – And Likely A Record-Breaking Dry Summer

Aug 25, 2017

Lots of sunshine and warmer temperatures are in the forecast all over the Puget Sound region. Once again, the mantra is “no rain.” And if you’ve been feeling like this has been a very dry summer – you’re right.

KNKX weather expert Cliff Mass says he’s sure we’ll at least tie the record for the driest summer in Seattle history, going all the way back to 1914.

“No rain as far as I can see,” said Mass of the weekend forecast. He says the scattered clouds in the Puget Sound region will dissipate as a weak disturbance moves through and temperatures will gradually warm up as the weekend progresses.

Warming Up This Weekend

Mass says Friday’s temperatures will get up into the mid to upper 70s. Then they’ll hit the low 80s on Saturday and the mid-80s on Sunday and Monday.

“So it’s just going to get warmer and warmer. And it looks like there’ll be a weak cooldown mid-week, but no rain at all in the models at this point. Completely dry,” Mass said.

That means the region is looking at tying a record for the driest July and August, based on rain measurements at Sea-Tac airport.

“The record is .02 inches of rain and that’s where we are right now,” Mass said. So if there is no rain before Sept. 1, that means people here will have in fact experienced the driest July-August in over 100 years. 

“And I think we’ll tie it,” he said. “I think that’s pretty much in the bag, because the models indicate no rain at all, at least for the next week.”

Persistent High Pressure Has Locked In Dry Skies

Mass says the driving force behind the dry weather is a persistent area of high pressure over us, with low pressure to both sides over the Pacific Ocean and on the East Coast.

“And this pattern has been locked in,” Mass said. “High pressure gives us sinking air, often offshore flow and that has basically ended any chance of precipitation.”

That has also prevented the occurrence of much in the way of lightening, Mass says, which has led to a relatively mild wildfire season in the Northwest, despite the extremely dry conditions.

To hear the full conversation, including a discussion of Cliff's experience of totality during last week's eclipse and its numerous meteorological effects, you can click on the 'play' icon at the top of this post. 

Weather with Cliff Mass airs at 9:02 a.m. Friday, right after BirdNote, and twice on Friday afternoons during All Things Considered. The feature is hosted by KNKX environment reporter Bellamy Pailthorp. Cliff Mass is a University of Washington professor of atmospheric sciences, a renowned Seattle weather prognosticator, and a popular weather blogger. You can also subscribe to podcasts of Weather with Cliff Mass shows, via iTunes or Google Play.