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Flash Flood — Hamlin, SD

Jun 28, 2025

Flood Cause
Heavy Rain

A volatile atmospheric setup on the afternoon and evening of June 28th led to the development of several powerful supercell thunderstorms across far eastern South Dakota. These storms produced multiple tornadoes, including two that caused significant damage in Deuel County. The strongest tornado was rated as a high-end EF3. Storms also produced large hail and instances of flash flooding from heavy rainfall.

Source: NOAA National Weather Service Storm Events Database (event 1277320). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Hamlin, SD

This event is one of many recorded floods in Hamlin County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Hamlin County flood data →

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