Lemhi County, Idaho
County storm and disaster record · FIPS 16059 · population 7,951 · 4,564 sq mi
NOAA's Storm Events Database holds 350 records for Lemhi County, Idaho from 1950 through June 30, 2026, on 252 days; the most frequent are winter storm records (149 records). 215 of them are forecast-zone records, which the National Weather Service files once per zone: a county covered by several zones receives each one, so a single storm can add several records on the same day. The deadliest single record is the July 22, 2003 wildfire: 2 deaths. FEMA has issued 5 declarations naming the county since 1984, 3 of them for natural hazards; the latest for a natural hazard was “Hurricane Katrina” on September 13, 2005.
The record, 1950 to 2026
Storm records filed for the county each year (2026 to June 30, 2026). Before 1996 NOAA recorded only tornadoes (from 1950), thunderstorm wind and hail (from 1955).
- recorded, no damage figure
- under $100,000
- $100,000 or more
- $1 million or more
- $10 million or more, or a death
- $100 million or more, or 10 deaths
- a year's colour: its recorded damage or deaths
- a year with a death
- 1955: wind and hail recorded from 1955
- 1996: all 48 event types from 1996
- Storm records
- 350on 252 days, 1950 to June 30, 2026
- Deaths recorded
- 34 injuries
- Damage, 2025 dollars
- $86Mas filed (scale steps before 1993)
- Tornadoes
- 3strongest F1
- FEMA declarations
- 5latest 2020
Source: NOAA NCEI Storm Events Database, records through June 30, 2026 (file revision 20260918); damage converted to 2025 dollars with the BLS CPI-U. Search the record at NCEI. BLS consumer price index.
What hazards hit Lemhi County most?
The most frequent records are winter storm records: 149 since 1996. The rank column places the county among Idaho's counties by days with a record per 1,000 square miles of land over each hazard's complete period.
| Hazard | Records | Days | First, last | Killed | Injured | Damage | Rank in state |
|---|---|---|---|---|---|---|---|
| Winter storms | 149 | 118 | 1996-2026 | 0 | 0 | $11K | 43 of 44 |
| Severe thunderstorm wind | 57 | 41 | 1976-2025 | 0 | 1 | $179K | 38 of 44 |
| High wind and dust storms | 37 | 29 | 1996-2025 | 0 | 0 | $763K | 39 of 44 |
| Hail | 32 | 20 | 1966-2024 | 0 | 0 | $645K | 40 of 44 |
| Floods | 27 | 23 | 1996-2026 | 0 | 1 | $83M | 36 of 44 |
| Extreme cold | 18 | 13 | 2006-2026 | 0 | 0 | – | 28 of 44 |
| Landslides and avalanches | 12 | 10 | 2003-2023 | 0 | 0 | $5K | 22 of 44 |
| Heavy rain | 8 | 6 | 2004-2014 | 0 | 0 | – | 31 of 44 |
| Tornadoes | 3 | 3 | 1956-1987 | 0 | 0 | $657K | 35 of 44 |
| Heat | 2 | 1 | 2024-2024 | 0 | 0 | – | 31 of 44 |
| Lightning | 2 | 2 | 1998-2010 | 1 | 2 | – | 21 of 44 |
| Wildfires | 2 | 2 | 2000-2003 | 2 | 0 | – | 39 of 44 |
| Fog, smoke and funnel clouds | 1 | 1 | 2009-2009 | 0 | 0 | – | 41 of 44 |
Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.
How many tornadoes has Lemhi County had?
NOAA records 3 tornadoes in Lemhi County from 1956 to 1987, the strongest rated F1, with 0 deaths and 0 injuries recorded in the county. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.
Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 3 tornadoes whose track touched Lemhi County since 1950 (NOAA's county records number 3, the same count); along their whole tracks they killed 0 people.
Map of the strongest tornado tracks in Idaho.
Every tornado record filed for Lemhi County (3)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 1987-06-15 | Lemhi County | F1 0.1 mi x 20 yd | 0 | 0 | $250K step |
| 1984-08-24 | Lemhi County | F1 0.1 mi x 7 yd | 0 | 0 | $3K step |
| 1956-06-01 | Lemhi County | F1 0.5 mi x 33 yd | 0 | 0 | $30 step |
A damage figure marked "step" is a record from before 1993: NOAA then filed damage by category, and the figure is the category as entered, in the dollars of that year, not an estimate of the loss.
Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.
When was the last damaging storm in Lemhi County?
The most recent record with damage, injuries or deaths is the December 17, 2025 high wind ($15,000 in damage in 2025 dollars).
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-05-17 | Winter WeatherLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2026-04-25 | Frost/FreezeLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2026-01-27 | FloodTendoy, Lemhi County | 0 | 0 | – | |
| 2025-12-21 | Winter WeatherLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2025-12-18 | Winter WeatherLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2025-12-17 | High WindLemhi County · forecast zone Eastern Lemhi County | 66 kt wind | 0 | 0 | $15K |
| 2025-12-17 | High WindLemhi County · forecast zone Western Lemhi County | 63 kt wind | 0 | 0 | $5K |
| 2025-12-04 | Winter WeatherLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2025-06-21 | Winter WeatherLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – | |
| 2025-06-19 | Thunderstorm WindLeadore, Lemhi County | 70 kt wind | 0 | 0 | $70K |
| 2025-02-07 | Winter StormLemhi County · forecast zone Western Lemhi County | 0 | 0 | – | |
| 2025-02-07 | Winter StormLemhi County · forecast zone Eastern Lemhi County | 0 | 0 | – |
Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.
The deadliest and costliest records
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2003-07-22 | WildfireShoup, Lemhi County Two fire fighters were killed on the Cramer Fire, 17 miles west of Shoup in western Lemhi County. Several days of hot and dry conditions caused the Cramer Fire to expand rapidly. The fire fighters were killed near a helipad waiting for a helicopter to pick them up, when the fire over took them. | 2 | 0 | – | |
| 2010-08-10 | LightningCarmen, Lemhi County A 37 year old man riding a horse was struck by lightning and killed. | 1 | 0 | – | |
| 1998-06-25 | LightningLeadore, Lemhi County A couple of Bureau of Land Management employees were struck by lightning while in a car. They were off from work for at least 5 days following. | 0 | 2 | – | |
| 2010-08-05 | Thunderstorm WindCarmen, Lemhi County Winds were measured by the Kriley Creek RAWS. | 56 kt wind | 0 | 1 | – |
| 1996-02-08 | FloodLemhi County · forecast zone Western Lemhi County Major flooding took place the second week of February in Northern Idaho. Conditions that developed in late January contributed significantly to the flood. Large amounts of low elevation snow fell during the third week of January, especially in Northern Idaho where valley locations reported 10 additional inches of snow ... | 0 | 1 | $83M |
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 1996-02-08 | FloodLemhi County · forecast zone Western Lemhi County | 0 | 1 | $83M | |
| 2013-08-01 | HailSalmon, Lemhi County | 1.00 in hail | 0 | 0 | $621K |
| 2016-12-20 | High WindLemhi County · forecast zone Eastern Lemhi County | 52 kt wind | 0 | 0 | $615K |
| 2025-06-19 | Thunderstorm WindLeadore, Lemhi County | 70 kt wind | 0 | 0 | $70K |
| 2025-12-17 | High WindLemhi County · forecast zone Western Lemhi County | 63 kt wind | 0 | 0 | $5K |
| 2013-09-05 | Thunderstorm WindNorth Fork, Lemhi County | 76 kt wind | 0 | 0 | $1K |
Before 1993 NOAA filed damage by category, not amount, so the list above starts in 1993. The highest category filed here before then (entered as $250K, in the dollars of the day) holds: June 15, 1987 (tornado, Lemhi County).
Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.
Is it getting more frequent?
Records per decade for Lemhi County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).
| Hazard | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020-26 |
|---|---|---|---|---|---|---|---|---|
| Winter storms | – | – | – | – | 21 | 54 | 44 | 30 |
| Severe thunderstorm wind | 0 | 0 | 4 | 1 | 5 | 23 | 19 | 5 |
| High wind and dust storms | – | – | – | – | 1 | 19 | 10 | 7 |
| Hail | 0 | 1 | 1 | 4 | 2 | 14 | 9 | 1 |
| Floods | – | – | – | – | 3 | 7 | 13 | 4 |
| Extreme cold | – | – | – | – | 0 | 4 | 8 | 6 |
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
Records by month in Lemhi County. The two busiest months are in violet.
The values, month by month
Jan 31 · Feb 32 · Mar 17 · Apr 15 · May 20 · Jun 31 · Jul 42 · Aug 54 · Sep 25 · Oct 19 · Nov 21 · Dec 43 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Lemhi County
FEMA's register lists 5 declarations that include Lemhi County: 3 major disasters, 2 emergencies and 0 fire management assistance declarations. Most were for biological (2) and hurricane (1).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2020-04-09 | DR-4534 | Biological | Covid-19 Pandemic |
| 2020-03-13 | EM-3467 | Biological | Covid-19 |
| 2005-09-13 | EM-3244 | Hurricane | Hurricane Katrina |
| 2000-09-01 | DR-1341 | Fire | Wildfires |
| 1984-02-16 | DR-697 | Snowstorm | Ice Jams and Flooding |
Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.
How many floods has Lemhi County had?
NOAA's Storm Events Database holds 27 flood or flash flood records for Lemhi County from 1996 to 2026, on 23 days, with 0 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Lemhi County ranks 2020th of 2,942 U.S. counties.
The National Flood Insurance Program has paid $267,000 on 24 claims filed in Lemhi County; the most in one year was 3 in 2010. Claims count insured losses only: uninsured flood damage is not in this file.
The values, year by year
1982: 1 · 1984: 2 · 1985: 2 · 1986: 2 · 1997: 2 · 2009: 1 · 2010: 3 · 2011: 1 · 2012: 1 · 2013: 1 · 2015: 3 · 2017: 3 · 2023: 2; the other years: 0.
Source: FEMA OpenFEMA NFIP Redacted Claims, as of September 8, 2026; claims by year of loss, payments in the dollars of the year paid. OpenFEMA dataset page.
FEMA's modeled risk for Lemhi County
FEMA's National Risk Index rates Lemhi County Very Low overall, with an expected annual loss of $11.4 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.
| Hazard | Risk rating | Expected annual loss | Modeled frequency |
|---|---|---|---|
| Landslide | Relatively Moderate | $139K | 4.1 a year (modeled) |
| Wildfire | Relatively Moderate | $2.0M | once in about 241 years (modeled) |
| Lightning | Relatively Moderate | $591K | 31 a year (modeled) |
| Riverine Flooding | Relatively Low | $7.9M | once in about 2 years (modeled) |
| Cold Wave | Relatively Low | $383K | about once a year (modeled) |
| Avalanche | Very Low | $1K | once in about 100 years (modeled) |
| Earthquake | Very Low | $288K | once in about 51 years (modeled) |
| Winter Weather | Very Low | $17K | 28 a year (modeled) |
Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.
Counties that share a border with Lemhi County
Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.
Next
- Tornadoes in IdahoEvery Idaho tornado since 1950 and the counties with the most per square mile
- Winter storms in IdahoThe state's winter storm records, by county, year and month
- The Idaho recordEvery hazard in the state, its deadliest events and its federal declarations
- FEMA's risk rating for each hazard in Lemhi CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Lemhi County's FEMA declarations (CSV)5 rows: every declaration that named the county, for your own analysis