Live
Active alerts for this county
Boise County, Idaho severe weather history spans 99 recorded events between 1961 and 2025. The dominant hazard is thunderstorm wind, accounting for 27.3% of all recorded events. It ranks #2,886 nationally and #23 in Idaho.
99
Recorded events
1
Direct deaths
6
Direct injuries
$251K
Property damage
The record
What the Boise County, Idaho severe weather history record shows
Across the archive, Boise County, Idaho severe weather history averages 1.5 recorded events a year. The busiest stretch on record is the 2020s, with 30 events logged in that decade alone. Roughly 5 events fall before 1990 and 94 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Boise County, Idaho record is thunderstorm wind, responsible for 1 direct deaths. The costliest is flash flood, with $100K in reported property damage. In total, 7 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Boise County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 27 | 1 | $51K | 78 | 1970–2025 |
| Hail | 21 | 0 | $0 | 2 | 1961–2024 |
| Flash Flood | 20 | 0 | $100K | 0 | 1997–2025 |
| Heavy Rain | 19 | 0 | $0 | 0 | 1996–2024 |
| Flood | 6 | 0 | $100K | 0 | 1998–2023 |
| Debris Flow | 5 | 0 | $0 | 0 | 1997–2024 |
| Wildfire | 1 | 0 | $0 | 0 | 2002–2002 |
Decade by decade
Boise County, Idaho severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Significant events
Deadliest events on record in Boise County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Aug 22, 2010 | Thunderstorm Wind | IDAHO CITY | 1 | 0 | $0 |
| Aug 8, 1993 | Thunderstorm Wind | 0 | 4 | $0 | |
| Aug 11, 1993 | Thunderstorm Wind | 0 | 1 | $0 | |
| Jun 15, 1987 | Thunderstorm Wind | 0 | 1 | $0 |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Forest Service Roads were washed out with debris flows. The top end of Fall Creek road was washed out and the West Fork of James Creek near Atlanta road was also washed out. A new washout scar was seen in the wilderness area near Jackson Peak on the Upper North Fork of the Boise River.
A small amount of water in a recently burned area with steep slopes allowed standing water to accumulate to 3 feet next to Hwy 21 near MP 80. This occurred around the same time as mudslides and rockslides on the same highway. While radar captured very little precipitation, this area was known to be susceptible to runoff, especially with the recent wild fires.
Rain amounts of 0.2-0.3 inches in an hour caused a debris flow that trapped cars near MP 103 of Hwy 21. This surprisingly small amount of water produced a mudslide because of two important reasons. First, the Wapiti burn scar last year burned very intensely in the flood location, leaving lots of ash and debris on the ground. Second, this portion of Hwy 21 is notorious for avalanches because of it's steep, fairly sparse forest. The very steep open slopes that were primed with ash allowed the small amounts of water to run off almost immediately, carrying debris and mud with it.
Context
Risk, population and federal disasters
Relatively Low
FEMA NRI risk rating
8,273
Population (ACS)
$476K
Median home value
7
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Apr 9, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Sep 18, 2012 | Fire | KARNEY FIRE | FM |
| Sep 13, 2005 | Hurricane | HURRICANE KATRINA | EM |
| Sep 1, 2000 | Fire | WILDFIRES | DR |
| Jan 4, 1997 | Severe Storm | SEVERE STORMS, FLOODING, MUD AND LANDSLIDES | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Boise County, Idaho?
99 events are on record between 1961 and 2025, causing 1 direct deaths and $251K in property damage.
What is the most common severe weather hazard in Boise County?
Thunderstorm Wind, with 27 recorded events — 27.3% of everything in the archive for this county.
How many federal disaster declarations cover Boise County?
7 federal disaster declarations from FEMA include Boise County, each tied to a specific incident period.
How risky is Boise County compared with the rest of the country?
FEMA's National Risk Index rates Boise County as relatively low risk, placing it in the 49 percentile of its state for expected annual loss.
Where does the Boise County, Idaho severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Blaine County 114
- Bonner County 125
- Bingham County 285
- Bonneville County 223
- Benewah County 50
- Boundary County 66
Cite this page
“Boise County, Idaho.” Severe Weather History. severeweatherhistory.com/county/idaho/boise-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.