Saint Louis, MO – Residents across the Illinois-Missouri border region are bracing for a prolonged and dangerous heat wave beginning Saturday afternoon and lasting through Tuesday evening. Heat index values are expected to climb as high as 106 degrees, with little relief overnight as low temperatures hover in the mid to upper 70s for several consecutive days.
According to the National Weather Service in St. Louis, an Extreme Heat Watch is in effect for multiple counties, including Jersey, Madison, Monroe, and St. Clair in Illinois, and Jefferson, St. Charles, St. Louis, and St. Louis City in Missouri. This extended period of high heat and humidity significantly increases the risk of heat-related illnesses.
Across the affected areas, including cities like St. Louis, Edwardsville, Belleville, and Alton, residents should take immediate precautions. Staying in air-conditioned environments is crucial, and those without access to reliable cooling should seek out public cooling centers. Drink plenty of fluids and avoid prolonged sun exposure, especially during the peak afternoon hours.
Historically, this region has experienced severe heat events in June, notably in 1933 and 1988. The extended duration of this upcoming heat wave, with consistent high heat index values and warm overnight lows, poses a serious threat. Car interiors can reach lethal temperatures quickly, so never leave children or pets in unattended vehicles.
Warnings remain in effect through Tuesday evening, and residents should continue to monitor local advisories for any updates or changes to the Extreme Heat Watch.