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NWS St. Louis Announces Changes To May 16, 2025 Tornado Damage Assessment

After a year-long review of new ground survey data and aerial imagery, NWS St. Louis made several adjustments to the May 16, 2025 tornado damage assessment. Read More >

Thunderstorms and associated heavy rainfall will be able to easily produce flash flooding across portions of Missouri and Illinois through this evening. A Flood Watch is in effect for the area through the evening. Stay alert while driving, never drive into water over the roadway!
The first round of hot and humid conditions for the season will hit us Tuesday-Wednesday. It's been some time since we've seen heat index values in the upper 90s to low 100s and our bodies aren't used to the heat stress yet. Take extra caution this week, stay hydrated, weather light colored, loose clothing, and monitor yourself and others for signs of heat illness.
Summer heat and thunderstorm chances will be the main impacts this week. Some thunderstorms will be capable of producing locally heavy rain at time, while temperatures combine with moisture to produce high heat index values Tuesday and Wednesday.