Flood Watch

Locations Affected

Saint Louis, MO ∙ Columbia, MO ∙ O'Fallon, MO ∙ Saint Charles, MO ∙ Florissant, MO ∙ Saint Peters, MO ∙ Vera, IL ∙ Lake Tekakwitha, MO ∙ Valles Mines, MO ∙ Barnhart, MO

Full Alert Message

Flood Watch National Weather Service St Louis MO 512 AM CDT Tue May 19 2026 ...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 PM CDT THIS AFTERNOON... * WHAT...Flash flooding caused by excessive rainfall continues to be possible. * WHERE...Portions of southwest Illinois, including the following areas, Madison IL, Monroe IL and Saint Clair IL and east central Missouri, including the following areas, Jefferson MO, Lincoln MO, Saint Charles MO, Saint Louis City MO and Saint Louis MO. * WHEN...Until 1 PM CDT this afternoon. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. * ADDITIONAL DETAILS... - Potential rainfall amounts of 1 to 2 inches, with localized higher amounts. These amounts will occur across areas that experienced heavy rainfall yesterday. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

---