Sep 11, 2024
An upper level trough passed across the Northern Rockies September 11, which allowed for numerous thunderstorms to develop in the afternoon. Thermodynamic and kinematic ingredients were sufficient for a few strong thunderstorms, mostly across Southwest Montana. Additionally, a series of thunderstorms moved across the Horse Gulch burn scar, which resulted in flash flooding.
Source: NOAA National Weather Service Storm Events Database (event 1211448). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Lewis And Clark County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.