Heat advisory issued as heat index could rise to 106 on Saturday

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Incoming Kennerly kindergarteners Andrew and Hailey enjoy the Popsicles that Principal Todd Morgan handed out.

The National Weather Service in St. Louis has issued a heat advisory that will be in effect as temperatures soar to a heat index of 106 degrees from 9 a.m. to 8 p.m. Saturday.

Heat index values between 100 and 106 are expected from the late morning to early evening hours on Saturday due to temperatures in the mid-90s and dewpoints in the lower 70s, the NWS said.

The heat and humidity may cause heat stress during outdoor exertion or extended exposure. The very young, the elderly, those without air conditioning and those participating in strenuous outdoor activities will be the most susceptible. Also, car interiors can reach lethal temperatures in a matter of minutes.

The affected areas are St. Louis County, St. Louis city, Jefferson County,Monroe County, St. Charles County, Franklin County, Madison County, Bond County, Montgomery County, Lincoln County, Warren County, Clinton County, Macoupin County, Gasconade County, Ste. Genevieve, Washington County, Calhoun County, Jersey County, Greene County and Randolph County.