Weather Blog

Last weekend was the sunniest weekend in Seattle EVER!!!*

Last weekend was the sunniest weekend in Seattle EVER!!!*

It's a weekend you can tell your grandkids about some future February when they're getting ready to slosh through some slush on their way to a 2-hour delayed school day: "I remember the great sunny weekend of Feb. 20 in Aught-ten.  Blue skies as far as the eyes could see, and nary a cloud in sight. The air was so crisp, I could watch the Olympic events on Whistler from Kerry Park. In fact, to get there, I had to walk up Queen Anne hill with my sunglasses on -- both ways!!!!"

Yes, the statistics confirm that this past weekend was the sunniest weekend ever recorded in Seattle*.

OK, some of you might have noticed the little asterisk. That's because it was actually a tie, or at least, I assume it's a tie.

Here's the deal: both Saturday and Sunday rated a '0' on the 0-10 scale the National Weather Service uses to rate how obscured the sky was. To recap from Friday's blog, I believe it's calculated by a sun sensor that tallies the number of minutes it recorded sun and divides by the number of minutes in the day to get a ratio.  So if it recorded sun for 80 percent of the daylight minutes, that would mean the day rated a '2' on the cloud scale. Anywhere from 0-3 is considered an official sunny day. (And I'm not sure Sequim is abiding by that rule when they claim "300 days of sunshine a year", but I digress :) )

Now, scoring back-to-back zeros means the sensor didn't record any time during the entire weekend when the sun was obscured -- in essence, a perfect sunshine score. The asterisk comes in because admittedly, this is akin to saying: "I bowled a 300 game -- the best game ever bowled in the history of mankind!" Even though it's been done many times before, no one has actually bowled a higher score.

Update: I did go back through to Feb. 2005. the farthest back we have online records for these "sunshine scores". There are only seven instances where we had back-to-back perfect score days (two of which were three-day streaks), but none of them occurred over a weekend and all of them with the exception of one were in summer.

The exception was Feb. 2005, which is the gold standard for sunny recent sunny Februarys. That month saw a 10-day official sunshine streak from Feb. 15-24, starting off with three '0' scores, but those dates were Tuesday through Thursday. The weekend during that stretch rated a '0' and '1' and the highs were 48 and 50, as opposed to the pair of 57s we had this weekend, so I think 2010 wins. But 2005 does win on sunshine duration, as that 10 days went 0,0,0,1,1,0,1,2,1,0 on the sun scores.

The clear skies did make for some spectacular sunsets. Here is one taken from West Seattle by Brian Coy:

In the meantime, enjoy Monday's sunshine too -- which will likely make the first official six-day streak of sunshine since Sept. 2008.  I get the sense we'll be seeing lots of "10s" appear on the climate chart soon -- meaning it could be the cloudiest day in Seattle history!!!*