Excessive Heat — Minnehaha, South Dakota

2012-07-18 to 2012-07-24 · Minnehaha, South Dakota

Event narrative

Temperatures reaching the 90s to a few degrees above 100, and high humidity with dew points in the 70s, caused an extended period of excessive heat. The heat index peaked at 100 to 110 degrees each day, and did not fall enough at night to provide much relief to indoor locations that were not otherwise cooled. The excessive heat resulted in numerous heat related health complaints at the Sioux Falls air show on July 21st and 22nd. At least 10 people were transported to area hospitals and treated for heat exhaustion.

Wider weather episode

A combination of high heat and humidity persisted for several days. Daytime temperatures reached the 90s to several degrees above 100, and dew points were in the 70s. The heat index went as high as 110 degrees. Low temperatures were in the 70s, leading to some uncooled indoor locations remaining excessively warm through the night. The dangerous nature of the heat was added to by its continuing over a period of several days. The excessive heat caused an unknown number of heat related illnesses, including at least 10 people transported to area hospitals from the Sioux Falls air show during the weekend of July 21st and 22nd.

Source: NOAA Storm Events Database, event_id 401868. Narrative written by the NWS forecast office that issued the report.