Heavy Rain — Lemhi, Idaho

2013-09-05 · near Salmon, Lemhi, Idaho

Event narrative

The Salmon RAWS, located at 5,100 ft. MSL, reported 0.58 of rainfall in one hour. According to radar storm echo trends, the rain could have fallen in less than 30 minutes time.

Wider weather episode

Strong rising air associated with the nose of a 50 knot mid-level south-southwest jet combined with near record high moisture levels and an unstable atmosphere triggered wet multicellular thunderstorms over Lemhi County by late afternoon on September 5th. Flash flooding and power outages were the main impacts. To get an understanding how moist the air mass associated with this southwest surge was, the Boise weather balloon sounding recorded the 2nd highest moisture level (precipitable water values) on record on the evening of the 5th.

View location on OpenStreetMap → (45.1490, -113.9450)

Source: NOAA Storm Events Database, event_id 474054. Narrative written by the NWS forecast office that issued the report.