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Flood in Flathead County, Montana
18 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.
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.
Flathead County, Montana, has 18 flood events in the NCEI record since 1950, with at least one in 10 different years.
May is the busiest month, with 7 of the recorded events. The last 20 years account for 11 events against 7 in the 20 years before, a change that reflects reporting practice as much as weather.
The county holds 1.5% of the 1,175 flood events recorded in Montana; its 0.4 per 100 square miles compares with 0.8 statewide.
Compared with Montana
| Measure | Flathead County | Montana | US |
|---|---|---|---|
| Flood events since 1950 | 18 | 1,175 | 183,559 |
| Per 100 square miles | 0.4 | 0.8 | 5.2 |
| Per 10,000 residents | 1.7 | 10.6 | 5.5 |
| Deaths recorded | 0 | 9 | 2,961 |
| Busiest month | May | June | June |
By year
Seasonality
0Feb
0Mar
0Apr
1May
7Jun
7Jul
2Aug
0Sep
0Oct
0Nov
1Dec
0
Recorded events
All 18 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.
| Date | Event type | Magnitude | Property damage | Crop damage | Deaths | Injuries | Geography |
|---|---|---|---|---|---|---|---|
| 29 Jun 2026 | Flood | — | — | — | — | — | County |
| 28 May 2026 | Flood | — | — | — | — | — | County |
| 15 Jun 2022 | Flash Flood | — | $500K | — | — | — | County |
| 12 Jun 2022 | Flood | — | — | — | — | — | County |
| 31 May 2020 | Flood | — | — | — | — | — | County |
| 22 May 2016 | Flood | — | $35K | — | — | — | County |
| 14 May 2013 | Flood | — | — | — | — | — | County |
| 13 May 2013 | Flood | — | — | — | — | — | County |
| 13 May 2013 | Flood | — | — | — | — | — | County |
| 11 Jun 2011 | Flood | — | — | — | — | — | County |
| 13 Jul 2009 | Flash Flood | — | — | — | — | — | County |
| 5 Nov 2006 | Flash Flood | — | $7.0M | — | — | — | County |
| 15 Jun 2006 | Flash Flood | — | — | — | — | — | County |
| 15 Jun 2006 | Flood | — | — | — | — | — | County |
| 15 Jun 2006 | Flood | — | — | — | — | — | County |
| 16 May 2006 | Flood | — | — | — | — | — | County |
| 19 Jul 2004 | Flash Flood | — | $20K | — | — | — | County |
| 24 Apr 1996 | Flood | — | — | — | — | — | County |
Questions and answers
How many flood events has Flathead County had?
18 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 Flathead County?
29 Jun 2026 (Flood). Records reach NCEI about 120 days after the month ends.
What was the most damaging flood event recorded in Flathead County?
The flash flood of 5 Nov 2006, with property damage estimated by NCEI at $7.0M.
How does Flathead County compare with Montana for flood?
0.4 events per 100 square miles against 0.8 statewide; the county holds 18 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.