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Big Horn County, Montana Flood Zones

Check an Address in Big Horn County

Enter any address in Big Horn County, Montana to see its FEMA flood zone

The Flooding Character of Big Horn County

Flash flooding from heavy thunderstorms is the dominant flood character in Big Horn County. Recent events include flash flooding on June 8, 2023, caused by slow-moving, moisture-laden thunderstorms, and widespread flooding on March 23, 2019, due to rapid snowmelt on frozen ground, which also led to ice jams.

National Flood Insurance Program claims data indicates that properties in Zone A and Zone X_Unshaded have experienced flood damage. Claims in Zone A, for example, show an average payout of $57,761 with an average water depth of 2.0 feet. Homeowners in areas designated as Zone A or Zone X_Unshaded, as well as those in areas with unknown flood risk, should pay the most attention to flood preparedness.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Big Horn County

4 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read Montana flood stories →

Flood Risk Data for Big Horn County

Big Horn County, Montana has recorded 24 flood-related events since 1996 according to NOAA's Storm Events Database, including 13 flash floods and 11 river or area floods. The county has received 8 federal disaster declarations, 1 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Big Horn County Disaster History

FEMA Disaster Declarations (1978–2021)

Disaster Declarations
8
Flood/Coastal Disasters
1
Latest Disaster
Pf Fire (2021-07-28)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Big Horn County

DeclarationTypeDate
Pf FireFireJul 28, 2021
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storms And FloodingSevere StormApr 4, 2011
Hurricane Katrina EvacuationHurricaneAug 29, 2005
Severe Winter StormsSevere StormApr 8, 2001
WildfiresFireJul 13, 2000
Severe Storms & FloodingFloodMay 29, 1978

Recorded Flood Events in Big Horn County

NOAA Storm Events Database (1996–2025)

Total Flood Events
24
River/Area Floods
11
Flash Floods
13
Total Property Damage
$4.0M
Flood Deaths
1

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Big Horn County

TypeDateDamage
Flash FloodJun 8, 20230.00K
FloodMay 27, 20190.00K
Flash FloodMay 26, 20190.00K
FloodMar 23, 20190.00K
FloodJun 1, 20150.00K
FloodMar 7, 20140.00K
FloodMar 6, 20140.00K
FloodMay 30, 20130.00K
FloodJun 1, 20130.00K
FloodFeb 22, 20120.00K

Big Horn County Flood History

Flash Flood — Jun 8, 2023

A very moist, easterly surface flow continued into the start of the second week of June. This resulted in dewpoints well above 50 degrees, as well as atmospheric precipitable waters over 1.00. Winds aloft continued to be light resulting in slow-moving, heavy thunderstorms. As a result, multiple flash flood events occurred across portions of central and south central Montana.

Flood — May 27, 2019

Several days of heavy rain, combined with snow melt from the northern Big Horn Mountains, resulted in areas of flooding across portions of Yellowstone, Big Horn and Powder River Counties.

Flash Flood — May 26, 2019

A strong jet streak moved over the forecast area during the late afternoon into the evening hours on the 26th. This jet streak provided for strong upper level divergence. |At the same time, a strong upper level disturbance moved over the forecast area. |All the above, combined with low-level moisture and wind shear, resulted in severe thunderstorms across portions of the Billings Forecast area.

Flood — Mar 23, 2019

Flooding occurred across many areas of south central and southeast Montana during the latter portions of the month. A considerable snow cover existed through the month. Surface and sub-surface ground temperatures remained frozen through the last week of March. Warming temperatures resulted in this snow to quickly melt. Widespread flooding occurred due to the snow melt not being able to soak in...

Flood — Jun 1, 2015

A very heavy and slow moving thunderstorm moved over Billings and Hardin during the evening hours on the 1st. Street and small creek flooding was reported.

Source: NOAA National Weather Service Storm Events Database.

Big Horn County NFIP Flood Insurance Claims

Total Claims Filed
13
Total Paid Out
$240,143
Avg Claim
$21,831
Avg Water Depth
1.9 ft

Claims by Flood Zone

A Zones (High Risk)
3
X Unshaded (Low)
2

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Big Horn County

FEMA assigns flood zone designations to areas in Big Horn County, Montana:

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.

View all flood zone types →

Flood Insurance in Big Horn County

Properties in Big Horn County, Montana 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.