Updated: Sunday, 5:50 P.m.
Normally, the west coast marine layer is our summertime buddy. A reliable seasonable companion through thick (deep and stubborn) and thin (shallow and quick to burn off), we count on its murky morning goodness to keep our Northwest summers living up to their comfortable reputation. The 'cloudy start/sunny finish/afternoon temperatures in the 70s' routine is as commonplace in Seattle in late August as be-frappuccino'ed walkers are at Green Lake.
We'd rather our summer soul mate took a day off tomorrow. The long-awaited solar eclipse gets under way just after 9 a.m., the very time of the morning that the marine layer often is just beginning to burn off. Right now, the low clouds are brewing at the ocean beaches, and a light westerly push overnight will wrap some of that cloud deck around the Olympics and into the Sound by dawn. Many of us will wake up to some morning cloud cover.
Hopefully the August sun, at least before it's eclipsed, goes to town in burning that overcast right back to the coastline before the solar show gets underway. However, if you find yourself at 9:08 a.m. beneath a blanket of fuzzy gray, you might want to consider a 'Plan B'...a way to get out of our atmospheric conditions so that you might experience our astronomical one instead. That backup plan should be as follows: head for the hills. The foothills, actually. The marine layer always lingers longer right around the waterfront in Puget Sound. If you can get east of it, and about 500' on up (most of our east side communities have places that qualify), you should be in good shape for seeing that sunshine fade away.
Temperatures will be in the low to middle 60s through the eclipse. It maxes out in Seattle at 10:20 a.m. with 92% obscuration of the sun, and the entire historical event will be a wrap by 11:38 a.m. Phew! Remember to wear proper safety gear, and if you didn't find those snazzy solar eclipse viewing glasses in time, you can always make an old-fashioned pinhole projector box (easy instructions at Shannon O'Donnell KOMO on Facebook). Not ideal, perhaps, but better than nothing!
Monday and Tuesday afternoons looks great--lots of non-eclipsed sunshine--and highs in the 70s to low 80s.
A change-up occurs on Wednesday, as a weak impulse of low pressure ripples in our direction. It will send increasing clouds our way, and hopefully a few showers get thrown in there by Thursday, too. Temperatures cool to about 70 degrees by then.
After that, the morning marine layer makes a comeback on Friday. And this time, it will be a welcome sight.
Have a great night, and happy solar eclipse-ing!
Meteorologist Shannon O'Donnell
The KOMO4 Forecast Team
Today's Record Temperatures