Excessive Heat — St. Louis, Missouri

2025-07-26 to 2025-07-29 · St. Louis, Missouri

Event narrative

Hot and extremely humid conditions led to heat index values over 105 degrees for several days. The heat index values peaked around 113 degrees. A total of 115 people were admitted to local hospital emergency departments for heat related illnesses in St Louis County and city from July 22 through 29th.

Wider weather episode

A period of hot and very humid weather began in mid July. Although thunderstorms brought some heat relief in the first few days, the heat and humidity expanded on July 22 and lasted through the 29th or 30th for many locations. While temperatures generally topped out in the mid 90s, extreme humidity led to heat index values near or over 110 degrees for a week or more.

Source: NOAA Storm Events Database, event_id 1280964. Narrative written by the NWS forecast office that issued the report.