Chicago walks a month in Seattle's gloomy sky shoes
Any Seattle transplants living in Chicago this January must have thought they brought the weather with them.
The "Windy City" needs a new nickname after spending a near-record 8 consecutive days under completely overcast skies this month. Between Jan. 22 and the 29th, they never saw even one peep of sunshine with the observer at Chicago's O'Hare Airport reporting 10 out of 10 on the cloud cover scale each day. It's their longest streak in 25 years and 4th longest streak on record, coming in behind the record 12-day gloom stretch between December 29-January 9 in 1991-92, according to Bill Snyder with WGN-TV.
It's a cloudy streak Seattleties could be proud of. In fact, it might have even outdone Seattle -- certainly has so recently. Going back five years, the longest streak of days I could find here was five 10s in a row, both in January 2013 and February 2012. The National Weather Service doesn't keep the data easily accessible beyond 5 years here so I don't know Seattle's all-time record, but eight would be a challenge.
Overall, Chicago netted 16 days in January completely overcast, making it their second-gloomiest January on record.
So, does Seattle have to cede our crown as GrayTown, USA?
While Chicago is leading Seattle in the gray this January, overall if you want to count up overall gloom scores, Seattle certainly still has plenty to brag about... if you want to brag about these sort of things.
Each day is given a percentage of cloud cover score ranging from 0 (totally sunny/0% cloud cover) to 10 (100% overcast all day) with a sliding scale in between based on percentages. (A day with 70 percent cloud cover would, for example, rate a 7.) Thus a "perfect" overcast score -- as in never seeing the sun -- for a 31-day month would be 310.
If you add up each day's 0-10 cloud score for January in Chicago, you get 251 -- or a daily average of 8.1. This past January, Seattle had a score of 211, for an average of 6.8, but EACH of our three months' prior nearly matches Chicago's gray January: October was 249, November was 247 (with only 30 days in the month so had a higher average score) and 250 in December. That second-gloomiest January on record for them? Routine autumn and winter out here.
And we've had some whopper months in the past five years that what they lacked in consecutive days with 10s, still made up for in nearly overcast days. December 2015 had a cloud score of 264, and December 2012 was a dark, dreary 272 for an average score of 8.8. In that month, the "sunniest" day was a 7, meaning nearly every day was considered cloudy.
Also backwards: Snow. Seattle has been sunnier, but snowier than Chicago this January. Seattle did get officially 3" of snow in the month, while Chicago had just 0.6".
As expected, we out-rained them 4.22" to 2.87" but then again, Chicago had two days in a row when they hit 0 for a low, so...Chicago still the winter champion overall. But just don't think you're going to steal our cloudy crown anytime soon.