Weather Blog

75 degrees -- rarer than the Loch Ness Monster

75 degrees -- rarer than the Loch Ness Monster
If it seems like it's taking a long time to kick into some seriously warmer weather, you are correct. Last year, we were heading toward the 80s as we ended the month while in 2008, we had already notched our first 90 on May 17.

This year, 72 is still our high water mark for temperature, with mainly 60s still dotting the forecast for the foreseeable future. Weather statistic guru Jason Phelps went back and checked just how rare is it that we go so long before our first really warm day -- in this instance, he chose 75 degrees.

It turns out, we're nearing Top 5 territory. Here are the latest 75 degree days throughout Sea-Tac history:

1) 1991: June 9
2) 1955: June 8
3) 2000: June 3
4) 1981: May 28
5) 1964: May 27
6) 1950: May 25
7) 1986: May 25
8) 1948: May 24

So as of today, we'll be tied for 6th latest, and long range models show pretty confidently we'll slide into at least fourth place on Friday, and odds look pretty good we'll make it past June 3rd for third place.

Trusting the models beyond then is dubious, but at face value as of today, the pattern is such that there is perhaps a chance of ekeing out a 75 sometime around the weekend after next. Too early to say though and it's in the realm we could be talking about latest ever.

Now, before you bemoan that such a late start to warmth means we are doomed to a cold summer, there is evidence to the contrary. 1991, where we had to wait until June 9 for a 75 degree day, had a July, August and September that were all quite warmer than normal, marked by a 99 degree day on July 23rd which is now tied for third-hottest day on record.

1955 was even a bigger boomerang. These records are for Sea-Tac Airport, but at the Downtown Federal Building, it was 74 on June 7, 87 on June 8... and a whopping 100 on June 9th (95 at Sea-Tac.) So that streak ended in a real hurry. However, the rest of that summer ended up much cooler than normal into September.

In fourth place, 1981 was home to what was the hottest week on record until last summer with two weeks in August that had a five-day streak over 90 including a 99 and 98 back-to-back.

The official forecast for this summer by NOAA is for average temperatures and a higher chance of below-normal rainfall. So we'll see what happens, but despite our lack of toasty weather so far, I wouldn't put the swim trunks and inner tubes on Craigslist just yet :)