Tuesday's dreariness was 3 times darker than solar eclipse day in Seattle
SEATTLE -- If it seemed like it was dusk at lunchtime on Tuesday, you weren't that far off from being right. In fact, it was actually darker during the noon hour Tuesday in Seattle than it was during the peak of the solar eclipse on Aug. 21!
A thick cloud layer courtesy of an moderately-strong inbound cold front did a fantastic job of not only dumping a decent amount of rain in the city, but blocking out the sun.
According to researcher Mark Albright with the UW Atmospheric Sciences Department, Tuesday was the darkest day as far as measured solar output at the UW in two years at a paltry 0.61 MJ/m2 (Mega joules/meter squared -- measure of energy output). That number sounds low and it is -- a summer day where we have extended daylight hours will net over 30 MJ/m2. It turns out that Tuesday was the darkest day since Dec. 12, 2015 at 0.56.
You can see how dark it was on this time lapse video which spanned about Noon-1:30 p.m. Tuesday.
But that's not all. Albright went and looked at the instant solar energy output during the peak of the solar eclipse in Seattle on Aug. 21 when the sun was about 92 percent obscured -- about 33 watts/meter squared. That was during a cloudless sky and the output jumped back to 819 W/m2 as the moon moved away and the eclipse ended.
Tuesday morning, the solar output peaked at 48 W/m2 at 9:45 a.m., then decreased steadily as the clouds thickened and rain fell during the cold front passage. At 12:13 and 12:22 p.m., solar output measured just 11 W/m2 -- just 33% of the sun energy of peak eclipse time!
And yes, Seattle noticed.
Though some found the silver lining:
And true to #SoNorthwest form, some locals actually enjoy the gray:
For those looking hoping for brighter days, there is good news in the forecast. Long range models suggest a large ridge of high pressure will build in next week for some sunnier skies for a while.