May 26, 2019
A slow-moving low pressure system was accompanied by unusually-high amounts of moisture, periods of steady of heavy rain, and some thunderstorms over north-central Montana during May 25th through the early morning of the 28th. In addition, relatively-high snow levels allowed rain to fall on lingering snowpack along the Rocky Mountain Front, where easterly upslope flow enhanced rainfall totals. Portions of the Rocky Mountain Front received as much as around 3 to 6 inches of total rainfall. Runoff
Source: NOAA National Weather Service Storm Events Database (event 818917). 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.