Editor's Note: The latest story on storm timing for Thursday, June 13 can be found here. Our original story continues below.
The Chicago area is seeing a blast of summery heat this week, but it could end with the threat of severe thunderstorms.
According to the Storm Prediction Center, most of the Chicago area is at a slight risk of severe storms on Thursday, the second of five prediction levels used by the SPC. The far western suburbs, including parts of DeKalb, LaSalle, Kendall and Grundy counties, are at an enhanced risk according to the latest guidance.
The main threats will be gusty winds, but other severe threats are also on the table according to forecast models.
Here’s what we know about the potential for severe storms.
Wednesday Afternoon
High temperatures are expected to soar into the upper-80s and even the low-90s across the area, according to forecast models. At least some sunshine will also help fuel the warm temperatures, with humidity slowly on the rise.
Local
Wednesday Evening
Clouds are expected to build into the area, sweeping across northern Illinois from northwest to southeast, according to forecast models.
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A dome of high pressure is expected to help tamp down any real development of showers and thunderstorms out ahead of a cold front that’s slowly pushing across the upper Great Plains, but a few widely scattered showers and storms could form late Wednesday or even into Thursday morning.
Thursday Morning
After a brief clearing period overnight, more clouds are expected to build in the morning, with the development of showers and thunderstorms possible.
It’s unlikely that any of the storms would reach severe limits, but there are still chances for gusty winds, frequent lightning and heavy rains with any storms that develop.
That round of storms is expected to end in the late morning hours.
Thursday Afternoon
Temperatures will once again warm into the upper-80s and low-90s, but humidity will also be on the rise, pushing heat indices into the low-to-mid 90s across the area.
Clouds will also start to build back in during the early afternoon hours ahead of the arrival of a cold front in the region.
Thursday Evening/Night
The possibility of severe weather roars to life in the late afternoon and into the evening, but the exact timing of their arrival is still being dialed in.
The Storm Prediction Center has upgraded most of the area to a slight risk of severe storms Thursday night, with gusty winds the main threats.
If supercells develop, which is possible given the deterioration of the high pressure dome over the area, then large hail could also occur in any storms that develop, along with the possibility of isolated tornadoes.
Those storms are expected to begin arriving around the time of the evening commute, and could sweep quickly across the area from northwest to southeast.
Friday
Cooler temperatures are expected, with highs near their seasonal averages in the low-80s across much of the area.
Some parts of the Chicago area that are closer to Lake Michigan could potentially see temperatures in the 70s thanks to breezes off the lake.
Weekend
Highs are expected to soar back into the 90s by Sunday, and a long-lasting heat wave could potentially grip the area for at least a week, according to the National Weather Service’s long-range forecasting guidance.
