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Lemhi River near Lemhi

Highest listed crest 7.19 ftFlood stage 6.5 ft16 crests since 1971

The Lemhi River near Lemhi crested above flood stage 6 times among the 16 crests the National Weather Service lists from 1971 to 2026. The highest, 7.19 ft on June 21, 1984, was minor flooding, 0.69 feet above flood stage.

The gauge

Highest listed crest
7.19 ft
June 21, 1984; 2,430 cubic feet per second
Flood stage
6.5 ft
Major flooding from 10.0 ft
Crests at major
0
6 above flood stage
Most recent flood crest
January 29, 2026
7.07 ft, minor flooding
Location
Lemhi County
Idaho

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Lemhi River near Lemhi
Action stage6.05Jun 13, 2022The level at which the NWS or its partners begin to take action
Flood stage (minor)6.56Jan 29, 2026Minimal or no property damage, but possibly some public threat
Moderate flood stage8.50—Some inundation of structures and roads near the stream
Major flood stage10.00—Extensive inundation of structures and roads

Every listed crest

16 crests from 1971 to 2026. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Lemhi River near Lemhi, 1971 to 2026 46810ft Flood stage 6.5 ftMajor 10.0 ft Jun 27, 1971: 6.01 ft, action stage; 1,960 cubic feet per secondJul 6, 1975: 6.72 ft, minor flooding; 1,990 cubic feet per secondJun 24, 1982: 6.62 ft, minor flooding; 1,770 cubic feet per secondJun 21, 1984: 7.19 ft, minor flooding; 2,430 cubic feet per secondJun 2, 1986: 6.22 ft, action stage; 1,780 cubic feet per secondJun 5, 1995: 6.06 ft, action stage; 1,530 cubic feet per secondJun 10, 1996: 5.76 ft, below flood stage; 1,170 cubic feet per secondJun 17, 1999: 5.83 ft, below flood stage; 1,350 cubic feet per secondJun 22, 2009: 6.13 ft, action stage; 1,590 cubic feet per secondJun 17, 2010: 5.63 ft, below flood stage; 1,150 cubic feet per secondJun 24, 2011: 6.67 ft, minor flooding; 2,200 cubic feet per secondJun 5, 2017: 6.70 ft, minor flooding; 1,410 cubic feet per secondJun 1, 2018: 5.81 ft, below flood stage; 1,110 cubic feet per secondJun 13, 2022: 6.12 ft, action stage; 1,260 cubic feet per secondJun 2, 2025: 4.76 ft, below flood stage; 484 cubic feet per secondJan 29, 2026: 7.07 ft, minor flooding; 1,860 cubic feet per second Highest, 7.19 ft, Jun 21, 1984 19801990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Lemhi River near Lemhi 1970s: 1 1980s: 2 2 1990s: 0 2000s: 0 2010s: 2 2020s: 1 1970s1980s1990s2000s2010s2020s
  1. These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
  2. Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.

Highest crests

Highest listed crests, Lemhi River near Lemhi
1Jun 21, 19847.19+0.69Minor2,430
2Jan 29, 20267.07+0.57Minor1,860
3Jul 6, 19756.72+0.22Minor1,990
4Jun 5, 20176.70+0.20Minor1,410
5Jun 24, 20116.67+0.17Minor2,200
6Jun 24, 19826.62+0.12Minor1,770
7Jun 2, 19866.22−0.28Action1,780
8Jun 22, 20096.13−0.37Action1,590
9Jun 13, 20226.12−0.38Action1,260
10Jun 5, 19956.06−0.44Action1,530
11Jun 27, 19716.01−0.49Action1,960
12Jun 17, 19995.83−0.67Below flood stage1,350
13Jun 1, 20185.81−0.69Below flood stage1,110
14Jun 10, 19965.76−0.74Below flood stage1,170
15Jun 17, 20105.63−0.87Below flood stage1,150
16Jun 2, 20254.76−1.74Below flood stage484

Other gauges in Lemhi County

Flood gauges in Lemhi County
Salmon7.510.33 ft, Feb 7, 19854

Lemhi County: every hazard · River floods across the country · Idaho

NOAA National Water Prediction Service, gauge LERI1, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.