Sep 10, 1998
A funnel cloud was reported by a pilot (pirep) just northwest of Delta. Heavy thunderstorm rains caused flash flooding in eastern Washington county. Several roads were closed due to debris and flood waters. 1.59" of rain fell at the Zion National Park Headquarters that afternoon.
Source: NOAA National Weather Service Storm Events Database (event 5663920). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Washington County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.