We've struggled to shake the unseasonably cool temps for the last few weeks. We'll still struggle the next couple of days too. But by the weekend, and next week, there are some signs that our cool regime will turn around. Some 80s (maybe even 90s), that have been so elusive in our recent stretch, look to return.
For the last three and a half weeks, dating back to July 22nd, the area has been treated (or troubled, depending on your view of things) to temperatures far below normal. Only three times in that stretch have we eclipsed 80° for afternoon highs, none consecutively. This at the same time last year we were experiencing constant displays of heat.
In that stretch rain has been spotty, but thankfully we've picked up a couple timely soakings. And as you might expect with little rain, the humidity level has been low. I can't even think of the last time I had my air conditioning on!
The biggest reason by far for the seemingly early onset of fall, the jet stream. The Jet Stream's latest assessment (below) has been indicative of our recent stretch, a persistent northwesterly flow, allowing the cooler air that is usually bottled up north during the summer months into the upper midwest.
Occasionally this happens now and again during the summer. But rarely does it ever persist (more or less) for three and a half weeks. A blocking pattern, is to blame. It's a wind pattern that influences more north to south movement in the jet stream rather than being progressively moving west to east.
This pattern shift has yielded temperatures 3°F cooler over the last 30 days, with an average daily temperature during that stretch around 68°F.
Whether you like to see it or not, it appears summer isn't done yet. It appears a shift will be occurring to the jet stream. As soon as Sunday, but more pronounced by early next week. Check out the jet stream forecast by Tuesday morning, shifting north, allowing warmer air back into the upper midwest. 80s for sure look to return, possibly by Sunday, more likely by Monday. Heck, 90s may be in the future down the road too!
Just hold on you fall enthusiasts... your comfortably cool weather will return before you know it.
STORM TRACKER 6 CHIEF METEOROLOGIST