A dangerous stretch of heat is settling over the upper Midwest this weekend, and forecasters across Iowa and South Dakota are urging people not to shrug it off.
The National Weather Service has posted extreme heat warnings and advisories from eastern Iowa to the Sioux Falls area, with the worst of it expected Sunday and Monday. In many spots the heat index, the combination of temperature and humidity, will climb past 100 degrees, and forecasters in Iowa expect afternoon peaks between 105 and 110.
How hot it will get
The buildup is already underway. Around Cedar Rapids, dew points that sat in the mid 60s early Saturday are expected to reach the mid 70s by evening, pushing the heat index well into the 90s. That is only the beginning. Sunday and Monday have been flagged as First Alert Days, with several hours each day of a heat index at or above 100 and the potential to touch 110 during the afternoon and early evening. In Sioux Falls, a heat advisory takes hold at noon Saturday as highs climb into the mid to upper 90s, and counties to the south fall under a more serious extreme heat warning through the weekend…