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Flood in Ravalli County, Montana

22 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.

22 events · 1 deaths recorded · peak month May · county share of state 1.9%

2021-07-01: Flood2020-05-20: Flood2018-05-10: Flood2018-05-10: Flood2018-05-08: Flood2017-06-13: Flood2014-05-27: Flood2014-05-24: Flood2014-03-06: Flood2014-02-12: Flood2014-01-11: Flood2008-11-12: Flood2008-11-12: Flood2006-11-07: Flood
Flood event locations in and around Ravalli County. Dots: Flood event locations in the kept record. Boundaries: US Census Bureau.

NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. Storm records through 30 Jun 2026.

Ravalli County, Montana, has 22 flood events in the NCEI record since 1950, with at least one in 10 different years.

May is the busiest month, with 8 of the recorded events. The last 20 years account for 13 events against 9 in the 20 years before, a change that reflects reporting practice as much as weather.

The county holds 1.9% of the 1,175 flood events recorded in Montana; its 0.9 per 100 square miles compares with 0.8 statewide.

NCEI attributes 1 death in the county to floods and flash floods.

Compared with Montana

MeasureRavalli CountyMontanaUS
Flood events since 1950221,175183,559
Per 100 square miles0.90.85.2
Per 10,000 residents4.810.65.5
Deaths recorded192,961
Busiest monthMayJuneJune

By year

195019882026
Flood events recorded in Ravalli County per year, 1950 to 2026 (2026 is partial).

Seasonality

Jan
1
Feb
1
Mar
1
Apr
0
May
8
Jun
1
Jul
6
Aug
1
Sep
0
Oct
0
Nov
3
Dec
0
Flood events in Ravalli County by month of occurrence, all years.

Recorded events

All 22 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.

DateEvent typeMagnitudeProperty damageCrop damageDeathsInjuriesGeography
1 Jul 2021Flash Flood—$15K$15K——County
20 May 2020Flood—————County
10 May 2018Flood—$1K———County
10 May 2018Flood—$1K———County
8 May 2018Flood—————County
13 Jun 2017Flood—$30K$1K——County
27 May 2014Flood—————County
24 May 2014Flood—————County
6 Mar 2014Flood—$16K———County
12 Feb 2014Flood—————County
11 Jan 2014Flood—————County
12 Nov 2008Flash Flood—$6K———County
12 Nov 2008Flash Flood—$6K———County
7 Nov 2006Flood—$60K———County
23 Aug 2003Flash Flood—————County
21 Jul 2001Flash Flood—————County
20 Jul 2001Flash Flood—————County
20 Jul 2001Flash Flood—————County
15 Jul 2001Flash Flood—————County
15 Jul 2001Flash Flood—————County
16 May 1996Flood—————County
16 May 1996Flood———1—County

Questions and answers

How many flood events has Ravalli County had?

22 events in the NCEI Storm Events record between 1950 and 2026. Reporting of floods and flash floods became far more complete after 1996, so early decades undercount.

When was the last recorded flood event in Ravalli County?

1 Jul 2021 (Flash Flood). Records reach NCEI about 120 days after the month ends.

What was the most damaging flood event recorded in Ravalli County?

The flood of 7 Nov 2006, with property damage estimated by NCEI at $60K.

How does Ravalli County compare with Montana for flood?

0.9 events per 100 square miles against 0.8 statewide; the county holds 22 of the state's 1,175 recorded events.

Provenance

NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026, public domain. County-recorded events plus zone-recorded events whose forecast zone is named for the county (marked "Forecast zone"). Population and area from the US Census Bureau (2021). Built 1 Oct 2026. See the methodology, the Flood hub and the county page.