Happy '0' Day, Seattle: Jan. 31, 1950 is only time it's been 0 degrees here
(Blog originally published Jan. 31, 2018. Lightly edited to update dates/years to 2019)
There's a saying that records are made to be broken, but the record low set in Seattle 69 years ago Thursday could stand the test of time, or at least our lifetimes.
For when Seattleites awoke on Jan. 31, 1950, it was a bone-chilling zero degrees outsides -- the cherry on top of the epicly brutal winter of 1950.
That temperature still stands today as Seattle's coldest reading in history, and aside from an equally impressive low of 1 degree on Feb. 1, no other cold blast has really come that close to matching that temperature before or after in the 130 or so years records have been kept here. Seattle's coldest low outside those two days is 6 degrees set three times that January, and twice more in the winters of 1968 and 1955.
Seattle hasn't been in single digits since 1989 with a 7 degree reading. 12 degrees is the coldest we've been in the past two decades.
The cold blast at the end of January probably felt especially cruel because it came after weeks of snowstorms and other record cold blasts peppered through the month -- including Sea-Tac's snowiest day on record with 20.0" on Jan. 13.
Even more so, Mother Nature faked everyone out "Lucy-with-the-football" style when temperatures finally - but briefly -- warmed up with a Pineapple Express type system on Jan 19-21. The high soared to 42 degrees on Jan. 19 with 1.07" of rain falling on top of the 7" of snow still on the ground. The next two days it would warm to 48 degrees each day with another nearly 2" total of rain, wiping out all of the snow on the ground.
Whew, brutally winter over, right? Wrong. By the 23rd it was down into the 30s again, and on the 24th it was a high of 26 and a low of 10, with a low of 7 coming up the next day as arctic air once again came pouring out of B.C.
It started snowing on the 25th with another 10" of snow on the 26th. That once again left Seattle buried under several inches of snow as another punch of arctic air rolled in on top of the cold air that was already there.
The morning of the 31st it was likely crystal clear as a massive arctic high settled in B.C., allowing any heat to easily radiate back into space with plenty of snow on the ground to act like a personal freezer.
It would get up to 20 that day, but drop to 1 degree again that night.
Another pair of single digit lows came on Feb. 2 and 3, then winter finally went away on Feb. 4.
The record arctic blast left several lakes frozen, including Green Lake and much of Gig Harbor! We didn't have an NHL team back then, but boy, it would have been easy to get in some outdoor practice!
By Feb. 13, 1950, Seattle would spend nearly a week in the 50s, with a 58 degree reading on Feb. 25. (Warm rain event again; don't think everyone was heading to Alki.)
Could Seattle ever get to 0 again?
It's very unlikely. As you just read it took a series of steps to go just right to get there, and looking at the hourly observations that night, it seemed there might have been some sort of brief cold push to get the temp down that low. According to Weather Underground's Sea-Tac hourly record archives, it was 6 degrees at 5 a.m., 1 degree at 6 a.m. (and probably dipped to zero in between the observations) and back to 7 degrees at 7 a.m.
And Seattle has grown up a lot since 1950. Urban areas keep more heat in at night due to concrete and asphalt doing a better job of holding in the day's heat than grass and vegetation, so even a similar set up today would likely be a few degrees warmer in the city.