Clark County, Idaho
County storm and disaster record · FIPS 16033 · population 783 · 1,763 sq mi
NOAA's Storm Events Database holds 477 records for Clark County, Idaho from 1950 through June 30, 2026, on 427 days; the most frequent are winter storm records (309 records). 390 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 January 3, 1998 avalanche, filed for the forecast zone Upper Snake Highlands, which covers the county: 2 deaths. FEMA has issued 4 declarations naming the county since 2005, 2 of them for natural hazards; the latest for a natural hazard was “Grassy Ridge Fire” on July 29, 2018.
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
- 477on 427 days, 1950 to June 30, 2026
- Deaths recorded
- 125 injuries
- Damage, 2025 dollars
- $9.0Mas filed (scale steps before 1993)
- Tornadoes
- 6strongest F1
- FEMA declarations
- 4latest 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 Clark County most?
The most frequent records are winter storm records: 309 since 1996. 45% of its winter storm records since 1996 fell in December and January. 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 | 309 | 285 | 1996-2026 | 4 | 4 | $412K | 13 of 44 |
| Severe thunderstorm wind | 54 | 41 | 1956-2026 | 0 | 0 | – | 26 of 44 |
| High wind and dust storms | 35 | 31 | 2002-2026 | 0 | 0 | $2.6M | 30 of 44 |
| Extreme cold | 22 | 20 | 2002-2023 | 0 | 0 | – | 9 of 44 |
| Wildfires | 15 | 15 | 2000-2022 | 0 | 0 | $40K | 26 of 44 |
| Hail | 10 | 8 | 1967-2014 | 0 | 0 | $10K | 39 of 44 |
| Floods | 9 | 9 | 2001-2025 | 0 | 0 | $895K | 35 of 44 |
| Landslides and avalanches | 9 | 9 | 1998-2026 | 8 | 1 | $2K | 13 of 44 |
| Tornadoes | 6 | 6 | 1964-2013 | 0 | 0 | $69K | 20 of 44 |
| Drought | 2 | 2 | 2001-2002 | 0 | 0 | – | 9 of 44 |
| Heat | 2 | 2 | 2002-2003 | 0 | 0 | – | 24 of 44 |
| Heavy rain | 2 | 2 | 1996-2014 | 0 | 0 | $5.0M | 34 of 44 |
| Fog, smoke and funnel clouds | 2 | 2 | 2022-2023 | 0 | 0 | – | 34 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 Clark County had?
NOAA records 6 tornadoes in Clark County from 1964 to 2013, the strongest rated F1, with 0 deaths and 0 injuries recorded in the county. That is 20th of 44 Idaho counties by days with tornadoes per 1,000 square miles since 1950. 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 8 tornadoes whose track touched Clark County since 1950 (NOAA's county records number 6: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 0 people.
Map of the strongest tornado tracks in Idaho.
Every tornado record filed for Clark County (6)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2013-09-17 | Dubois, Clark County | EF0 0.5 mi x 10 yd | 0 | 0 | – |
| 2005-05-09 | Dubois, Clark County | F0 0.5 mi x 30 yd | 0 | 0 | – |
| 1997-06-30 | Dubois, Clark County | F0 0.2 mi x 25 yd | 0 | 0 | $6K |
| 1995-06-05 | Clark County | F0 0.1 mi x 10 yd | 0 | 0 | $10K |
| 1991-03-25 | Clark County | F1 1 mi x 70 yd | 0 | 0 | $25K step |
| 1964-06-21 | Clark County | 0 | 0 | – |
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 Clark County?
The most recent record with damage, injuries or deaths is the April 16, 2026 winter weather (3 injuries and $10,000 in damage in 2025 dollars).
Multiple car crashes occurred around 7:40 a.m on U.S. Highway 20 between mileposts 378 and 380 at the Osborne Bridge, which blocked all lanes from Bull Moose Lane to Henry’s Fork. Fremont County Chief Deputy reported there was a single-car rollover that triggered a secondary two-car T-bone crash directly behind. Three people suffered injuries and were transported to the hospital. Around 4 inches of snow fell in the Island Park area.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1329913)
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-06-10 | High WindButte County and Clark County · forecast zone Beaverhead-Lemhi Highlands | 56 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindSmall, Clark County | 68 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindDubois, Clark County | 52 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindDubois, Clark County | 62 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindDubois, Clark County | 54 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindSmall, Clark County | 68 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindSmall, Clark County | 61 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindDubois, Clark County | 52 kt wind | 0 | 0 | – |
| 2026-05-13 | Thunderstorm WindDubois, Clark County | 52 kt wind | 0 | 0 | – |
| 2026-04-16 | Winter WeatherClark County and 2 more · forecast zone Centennial Mountains-Island Park | 0 | 3 | $10K | |
| 2026-04-15 | High WindButte County and Clark County · forecast zone Beaverhead-Lemhi Highlands | 57 kt wind | 0 | 0 | – |
| 2026-04-12 | Thunderstorm WindSmall, Clark County | 50 kt wind | 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 |
|---|---|---|---|---|---|
| 1998-01-03 | AvalancheClark County and 3 more · forecast zone Upper Snake Highlands During the first week of January, dangerous avalanche conditions prevailed in the mountainous regions of central and eastern Idaho. On January 3rd one avalanche killed a snowmobiler near Island Park. In the same area and at roughly the same time, a second snow snowmobiler was reported missing and presumed dead due to ... | 2 | 0 | – | |
| 2018-11-07 | Winter WeatherButte County and Clark County · forecast zone Beaverhead-Lemhi Highlands Light snow produced snow and slush covered roads and was declared a contributing factor to a motor home rollover resulting in the death of a 78 year old man at 1:53 pm MST near milepost 178 south of Spencer on southbound interstate 15. Idaho state police determined in their investigation that driving too fast for road ... | 1 | 1 | – | |
| 2026-02-22 | AvalancheClark County and 2 more · forecast zone Centennial Mountains-Island Park An avalanche occurred at around 2 pm on February 22nd in Carrot Canyon in the Centennial Mountains. Four snowmobilers were buried with 3 escaping but one fatality did occur. | 1 | 0 | – | |
| 2019-02-09 | Winter StormClark County and Fremont County · forecast zone Centennial Mountains-Island Park Extremely heavy snow fell in the Island Park area with the COOP observer reporting 15 inches and amounts of up to 18 inches reported by the public. The Crab Creek SNOTEL had 13 inches and White Elephant SNOTEL had 13 inches. The heavy snow and wind may have contributed to a snowmobile accident around 8 pm on the 10th ... | 1 | 0 | – | |
| 2018-01-20 | AvalancheClark County and 3 more · forecast zone Upper Snake Highlands A snowmobiler was killed by an avalanche near Island Park east of Reyes Peak just below the waterfall. | 1 | 0 | – | |
| 2018-01-10 | AvalancheClark County and 3 more · forecast zone Upper Snake Highlands A snowmobiler died due to an avalanche on January 10th near Island Park. | 1 | 0 | – | |
| 2015-12-23 | Winter StormClark County and 3 more · forecast zone Upper Snake Highlands Four to 8 inches of snow combined with high winds with gusts over 30 mph caused extemely difficult travel conditions with one fatality in an accident on US Highway 20 near milepost 367 on Ashton Hill at 8 am on the 23rd. This caused the road to be closed for several hours. | 1 | 0 | – | |
| 2015-11-05 | Winter WeatherClark County and 3 more · forecast zone Upper Snake Highlands A fatal accident occurred on Highway 20 14 miles north of Ashton due to snow and ice on the roadway. A man driving westbound near milepost 375 slid into oncoming traffic. | 1 | 0 | – |
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2014-08-01 | Heavy RainDubois, Clark County | 0 | 0 | $5.0M | |
| 2002-04-23 | High WindClark County and 3 more · forecast zone Upper Snake Highlands | 0 | 0 | $2.5M | |
| 2018-03-13 | FloodKilgore, Clark County | 0 | 0 | $799K | |
| 2026-04-16 | Winter WeatherClark County and 2 more · forecast zone Centennial Mountains-Island Park | 0 | 3 | $10K | |
| 1995-06-05 | TornadoClark County | F0 0.1 mi x 10 yd | 0 | 0 | $10K |
| 1997-06-30 | TornadoDubois, Clark County | F0 0.2 mi x 25 yd | 0 | 0 | $6K |
| 2025-12-24 | FloodSmall, Clark County | 0 | 0 | $3K | |
| 2000-01-22 | AvalancheClark County and 3 more · forecast zone Upper Snake Highlands | 0 | 1 | $2K |
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 $25K, in the dollars of the day) holds: March 25, 1991 (tornado, Clark 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 Clark 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 | – | – | – | – | 31 | 107 | 97 | 74 |
| Severe thunderstorm wind | 3 | 0 | 0 | 0 | 1 | 7 | 2 | 41 |
| High wind and dust storms | – | – | – | – | 0 | 5 | 6 | 24 z |
| Extreme cold | – | – | – | – | 0 | 9 | 8 | 5 |
| Wildfires | – | – | – | – | 0 | 8 | 5 | 2 |
| Hail | 0 | 1 | 1 | 0 | 3 | 4 | 1 | 0 |
High wind and dust storms in the 2020-26: 24 records against 6 in the decade before, 24 of them forecast-zone records. Cells marked z rose mostly through zone records. The local National Weather Service office files these once per forecast zone, so a change in how it draws its zones or splits a storm into records moves this count as much as the weather does; read it beside the Clark County days with a record above.
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
45% of its winter storm records since 1996 fell in December and January. The two busiest months are in violet.
The values, month by month
Jan 67 · Feb 79 · Mar 50 · Apr 24 · May 26 · Jun 23 · Jul 24 · Aug 22 · Sep 18 · Oct 14 · Nov 36 · Dec 94 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Clark County
FEMA's register lists 4 declarations that include Clark County: one major disaster, 2 emergencies and one fire management assistance declaration. Most were for biological (2) and fire (1).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2020-04-09 | DR-4534 | Biological | Covid-19 Pandemic |
| 2020-03-13 | EM-3467 | Biological | Covid-19 |
| 2018-07-29 | FM-5263 | Fire | Grassy Ridge Fire |
| 2005-09-13 | EM-3244 | Hurricane | Hurricane Katrina |
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.
FEMA's modeled risk for Clark County
FEMA's National Risk Index rates Clark County Very Low overall, with an expected annual loss of $1.4 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 |
|---|---|---|---|
| Avalanche | Relatively Moderate | $468K | once in about 15 years (modeled) |
| Wildfire | Relatively Low | $151K | once in about 323 years (modeled) |
| Landslide | Very Low | $2K | about once a year (modeled) |
| Earthquake | Very Low | $109K | once in about 45 years (modeled) |
| Volcanic Activity | Very Low | $1 | once in about 2,000 years (modeled) |
| Drought | Very Low | $1K | 93 modeled event-days a year |
| Winter Weather | Very Low | $15K | 27 a year (modeled) |
| Cold Wave | Very Low | $154K | 2.6 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 Clark 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 Clark CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Clark County's FEMA declarations (CSV)4 rows: every declaration that named the county, for your own analysis