Enter any address in Johnson County, Wyoming to see its FEMA flood zone
Flash flooding from intense rainfall events is the dominant flood character in Johnson County. Over the past 30 years, the NOAA Storm Events Database recorded 27 flash flood events and 13 flood events. Recent examples include minor flooding east-southeast of Barnum on June 4, 2023, following approximately an inch of rain in 20 minutes, and minor flooding of rural roads across the southern Bighorn Mountains on September 4, 2023, due to persistent moderate rain causing fast-rising streams.
While many reported flood events have resulted in no reported damage, National Flood Insurance Program (NFIP) claims have been filed in various zones. Claims in Zone X_UNSHADED averaged $4807, Zone A averaged $4695, and Zone X averaged $2790. Homeowners in areas prone to flash flooding, particularly those near creeks and streams, and those located in or near areas designated as Zone A, 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.
Johnson County, Wyoming has recorded 40 flood-related events since 1996 according to NOAA's Storm Events Database, including 27 flash floods and 13 river or area floods. The county has received 7 federal disaster declarations, 2 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1978–2024)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| House Draw Fire | Fire | Aug 22, 2024 |
| Wildfires | Fire | Aug 21, 2024 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms And Flooding | Flood | May 24, 2015 |
| 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 | Sep 4, 2023 | 0.00K |
| Flash Flood | Jun 4, 2023 | 0.00K |
| Flood | Jun 4, 2023 | 0.00K |
| Flood | May 27, 2019 | 0.00K |
| Flood | May 28, 2018 | 0.00K |
| Flash Flood | Jun 12, 2017 | 0.00K |
| Flood | May 25, 2015 | 5.00K |
| Flood | May 24, 2015 | 50.00K |
| Flood | May 24, 2015 | 0.00K |
| Flash Flood | May 24, 2015 | 0.00K |
Flash Flood — Sep 4, 2023
A large area of persistent moderate rain caused fast rising streams and creeks, leading to minor flooding of rural roads across the southern Bighorn Mountains.
Flash Flood — Jun 4, 2023
Almost an inch or rain fell around 20 minutes to the east-southeast of Barnum. Minor flooding occurred. No damage was reported.
Flood — Jun 4, 2023
A thunderstorm with heavy rain caused almost an inch of rain to fall within 20 minutes to the east-southeast of Barnum. Minor flooding occurred. No damage was reported.
Flood — May 27, 2019
Across Johnson County, two to four inches of rain fell from May 27th through May 28th. This caused rapid rises of creeks and streams as well as the Middle Fork of the Powder River. The river gauge at 10 miles upstream of Kaycee peaked at 10.3 feet, which is 2.3 feet above flood stage. In Kaycee, minor flooding occurred, especially around the fairgrounds but no damage was reported. Moderate floo...
Flood — May 28, 2018
Heavy rain brought flooding in portions of Johnson County north of Buffalo. Highway 193 near Fort Phil Kearney was closed due to flooding from Rock Creek. Water was also crossing Old Highway 87. No structural damage was reported.
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 Johnson 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 Johnson 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.