Weather Updates

‘Polar’ air will make it feel like autumn in July next week

Last summer it reached 84 degrees May people were hitting Oak Street Beach. Next week we may have low temperatures

Last summer, it reached 84 degrees in May and people were hitting the Oak Street Beach. Next week, we may have low temperatures in the 40s in mid-July. What gives? The "polar vortex,' of course. | Sun-Times File Photo

storyidforme: 69017146
tmspicid: 24466485
fileheaderid: 12207929
Graphic: July temperatures, then and now
Article Extras
Story Image

Updated: July 11, 2014 7:25PM

Don’t freak out. The “polar vortex” coming next week won’t be as bad as you think.

The coldest it is likely to get next week is somewhere in the upper 40s to mid-50s at night, forecasters say.

Around this time last year, Chicago’s high temperatures were in the mid-80s, and the city was about to begin a string of days in the low-to-mid 90s.

In contrast, by next Tuesday or Wednesday, temperatures will climb only into the low 70s, at best — that’s about 15 degrees below normal, according to the National Weather Service.

It’s due to a July version of the polar vortex — the phenomenon that pushed last winter’s temperatures below zero.

Andy Foster, a meteorologist at the National Weather Service Central Region Headquarters, said next week could feel like autumn, with highs reaching the upper 60s to low 70s; overnight lows will be in the upper 40s to mid 50s.

The temperature drop this year is due to a deep area of low pressure pushing cooler Canadian air farther south, Foster said.

Jeff Masters, director of meteorology for Weather Underground, said the previous long winter is also partly to blame.

Both meteorologists agree the term “polar vortex” isn’t exactly the best term to refer to what’s happening.

“What a better term would be is ‘a polar air outbreak,’” Masters said. “We’re getting air from northern Canada that’s moving southward and it looks similar to the winter time polar vortex pattern, but not quite as cold.”

According to Foster, the cooler summer is not affecting how warm or cool the winter may be and also has little to do with global climate change.

“One event like this doesn’t dictate or tell us anything about global warming or cooling,” Foster said. “It’s just one weather event. When we talk about climate change, we’re talking about a long-term thing.”

It’s not unusual to get a few days of chillier weather in July, Masters said. And weather experts are not expecting Chicago temperatures to break any records.

“This sure beats 95 [degrees] and humid,” Masters said. “So I’ll take it.”

It was a view apparently shared by many people spending time outside Friday. Some were taking a break from work; others were on their way to the beach — and regardless of all the “polar” predictions, there were no signs of anyone trying to bundle up.

Amanda Porter, eating lunch with friend Paul Doraski along the Chicago River, said the city is known for unpredictable weather, after all, so she isn’t surprised to hear the “polar vortex” isn’t going away.

“When I heard about it, I just said, ‘Oh, look — it’s Chicago.’ ”


Twitter: @mlespana

© 2014 Sun-Times Media, LLC. All rights reserved. This material may not be copied or distributed without permission. For more information about reprints and permissions, visit To order a reprint of this article, click here.