National Weather Service United States Department of Commerce

A broken line of thunderstorms is expected to move into northeast Missouri and west central Illinois this evening between 900-1000 PM. The storms will be weakening as they move southeast, but a few could be strong to severe during the evening into the early overnight hours. Damaging wind gusts up to 60 mph are the primary threat. 1 inch hail is also possible. As the storms continue moving southeast overnight, they are expected to continue weakening and eventually dissipate. The best chance for rain will be across northeast Missouri into west central Illinois, but farther south and east the storms will likely break up enough that most areas will receive little if any rain.
Hot and humid weather will persist through next week. By Monday and Tuesday, temperatures will be near 100 in a number of locations. This combined with high humidity will create dangerous heat index values between 100 and 107 degrees during the afternoon hours on Monday and Tuesday. However, there is a chance that Tuesday could end up a bit cooler if a cold front moves in sooner than currently forecast. If you must be outside, take frequent breaks, wear light-colored, loose fitted clothing and drink plenty of water!