Excessive Heat in Shiawassee, Michigan

During the afternoon and evening hours, heat index values at Owosso reached 100 to 105 degrees. While the heat index did not reach 105 for 3 hours, overnight heat index values never fall below 85 degrees.

The end of June marked the beginning of a prolonged period of extreme heat across much of southeast Michigan. This heat wave continued into early July. Most areas saw heat index values climb to around or above 105 with little to no relief during the overnight hours. For some locations, overnight heat index values remained around or above 80 degrees. While heat index values may not have reached 105 for 3 hours on June 30th, this was the first day of a heat wave that brought a prolonged period of extreme heat with little to no relief during the overnight hours.