Enter any address in Big Horn County, Wyoming to see its FEMA flood zone
Flash flooding from thunderstorms and general flooding from snowmelt and heavy rain are the dominant flood types in Big Horn County. Recent events include flash flooding on July 20, 2024, near Shell Creek, where culverts were plugged and a resident's bridge was washed out. Minor flooding also occurred around Medicine Lodge State Park on June 4, 2021, due to rapid snowmelt.
National Flood Insurance Program data shows that while Zone A areas have experienced the most claims and highest average payouts, claims have also occurred in Zone X and Zone X_Unshaded areas, with one claim in an unknown zone showing significant water depth. Residents in low-lying areas, near creeks and rivers, and those whose homes are not built to the Base Flood Elevation should pay the most attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
14 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Big Horn County, Wyoming has recorded 30 flood-related events since 1996 according to NOAA's Storm Events Database, including 10 flash floods and 20 river or area floods. The county has received 4 federal disaster declarations, 1 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1978–2020)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Flooding, And Landslides | Severe Storm | May 18, 2011 |
| Severe Storms, Flooding & Mudslides | Flood | May 29, 1978 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jul 20, 2024 | 10.00K |
| Flood | Jun 4, 2021 | 0.00K |
| Flood | May 27, 2019 | 0.00K |
| Flood | May 27, 2018 | 0.00K |
| Flood | Jun 22, 2017 | 0.00K |
| Flood | Feb 10, 2017 | 0.00K |
| Flood | Jun 2, 2017 | 0.00K |
| Flash Flood | May 15, 2015 | 2.00K |
| Flash Flood | Jun 7, 2015 | 5.00K |
| Flash Flood | Jun 5, 2015 | 0.00K |
Flash Flood — Jul 20, 2024
Three thunderstorms with heavy rainfall moved over the Trapper Creek drainage in short succession during Saturday afternoon, causing localized flash flooding near the confluence of Trapper Creek and Shell Creek. Culverts were plugged and at least one resident's driveway bridge was washed out. Boulders the size of wheelbarrows were moved onto agricultural land and damaged fences. A large number ...
Flood — Jun 4, 2021
Very warm temperatures caused rapid snowmelt in the Bighorn Mountains and brought minor flooding around Medicine Lodge State Park. The flooding remained in the low lying areas near the Big Horn River and caused no damage.
Flood — May 27, 2019
A persistent area of low pressure brought one to three inches of rain to portions of the eastern Big Horn Basin. The result was minor flooding in Worland and Medicine Lodge State Park. In Ten Sleep Canyon, two small mudslides occurred.
Flood — May 27, 2018
A combination of rain and snow melt produced minor flooding around Medicine Lodge Creek as the creek rose to flood stage. Flooding remained in low lying areas and caused no damage.
Flood — Jun 22, 2017
A combination of rapid snowmelt, releases from the Boysen Reservoir and some log jams caused flooding along portions of the Greybull and Big Horn Rivers. The flooding remained over low lying areas and caused little or no property damage.
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Big Horn County, Wyoming:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Big Horn County, Wyoming that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.