Flash Flood — Grand, Utah

2010-08-19 · near Potash, Grand, Utah

Event narrative

Heavy rainfall within a short period of time resulted in flash flooding across the heavily used Mineral Bottom Road. Mineral Bottom Road was deeply washed out in the switchback section and an extensive amount of debris covered the road, which remained impassable as of mid September 2010. The road washout stranded 29 people who were airlifted by helicopter. The KGJX WSR-88D radar estimated 1.86 inches of rain within 60 minutes in the source region of the Mineral Bottom Road flash flood. The NPS' Island-In-The-Sky visitors center personnel measured 1.05 inches of rain, most of which fell within a half hour. Other locations in the area likely received flash flooding.

Wider weather episode

Monsoonal moisture resulted in strong thunderstorms which produced heavy rainfall, as well as hail and outflow winds that approached severe criteria.

View location on OpenStreetMap → (38.5124, -110.0030)

Source: NOAA Storm Events Database, event_id 250165. Narrative written by the NWS forecast office that issued the report.