County Hazards

Storm events on record through

Big Horn County, Wyoming Storm events, disaster declarations and flood insurance claims on record

This page is a county record of past events and claims. It does not show the flood zone or the risk of an address. For the flood map of an address, use FEMA's address search (opens in a new tab).

NCEI has 222 storm events on record for Big Horn County, Wyoming, from 1950 through 30 Jun 2026.

The newest event on record is a thunderstorm wind event on 1 Aug 2025.

FEMA has 4 disaster declarations on record for the county from 1964 through 1 Oct 2026. The newest is DR-4535 of 11 Apr 2020.

OpenFEMA has 9 NFIP claims on record for the county from 1978 through 8 Sep 2026. The NFIP paid $248 thousand on these claims.

The NWS collects event reports from a variety of sources, which include (but are not limited to): county, state, and federal emergency management officials, local law enforcement officials, SKYWARN spotters, NWS damage surveys, newspaper clipping services, the insurance industry, and the general public, among others.

The National Weather Service reports property and crop damage estimates using available data at the time of event reporting. These values should therefore be considered broad estimates. Damage amounts are not adjusted for inflation.

Zone (NWS Forecast Zone): A zone is a geographic area defined by the NWS for issuing forecasts, watches, and warnings. While zones often align with counties, they can also represent smaller or subdivided areas within a county to account for differences in weather conditions, such as elevation or proximity to water. Larger-scale events—such as heat, cold, drought, and winter storms—are typically recorded by zone.

The words of the agency. Source: NOAA NCEI, Storm Events Database, page "Frequently Asked Questions", copied on .

This is raw, unedited data from FEMA's National Emergency Management Information System (NEMIS) and as such is subject to a small percentage of human error.

The words of the agency. Source: FEMA, OpenFEMA Dataset "Disaster Declarations Summaries - v2", copied on . The page gives: last data refresh 2026-10-01.

It is derived from the National Flood Insurance Program system of record, staged in the program's reporting platform and redacted to protect policy holder personally identifiable information.

The words of the agency. Source: FEMA, OpenFEMA Dataset "NFIP Redacted Claims - v3", copied on . The page gives: last data refresh 2026-09-09.

Dates of the data: NCEI storm events through . OpenFEMA disaster declarations through . NFIP claims through .

Since the last update: no change is on record for Big Horn County. The site compares the agency data at each update. Updates of the data

The five hazards

Storm events on record for Big Horn County by hazard and period (NCEI, through 30 Jun 2026)
Hazard1950 to 20262000 to 20092010 to 20192020 to 2026Newest event
Hail6231193
Tornado33630
Flood303222
Wind87182824
Winter0000None on record
Other event types10Heat, cold, drought, wildfire, lightning, fog, tropical and other types
All storm events222607829

A hazard name opens the page of that hazard for the county. A hazard has a page from 10 events. The year 2026 has the events through 30 Jun 2026 only.

A county count has the events that NCEI gives to the county. It also has the events of a forecast zone that has the name of the county. A zone with another name counts for the state only.

Rates of Big Horn County beside the total of the counties of Wyoming and of the United States
MeasureBig HornAll counties of WyomingAll counties of the United States
Storm events for each 100 square miles, 1950 to 20267.110.549.3
Storm events for each 10,000 residents, 1950 to 2026190.9176.952.5
NFIP claims for each 1,000 policies in force, 2016 to 2025no figure55.9185.3

The columns for the state and the United States total the counties. They count the events of each county in the same way as the county column. The site gives a rate for each 10,000 residents only from 10,000 residents. Residents and area: Census Bureau, 2021.

Newest storm events on record

Thunderstorm Wind63 mph (55 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind67 mph (58 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind59 mph (51 knots, measured gust)

6 miles NE of HYATTVILLE

Thunderstorm Wind67 mph (58 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind58 mph (50 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind63 mph (55 knots, measured gust)

At COWLEY ARPT

Thunderstorm Wind69 mph (60 knots, measured gust)

At GREYBULL ARPT

Flash Flood

1 mile NE of SHELL. Damage estimate: $10 thousand

Thunderstorm Wind59 mph (51 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind59 mph (51 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind71 mph (62 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind61 mph (53 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind59 mph (51 knots, measured gust)

At GREYBULL ARPT

Hail1.25 in, half dollar size

5 miles SW of BYRON

Hail1.00 in, quarter size

6 miles NW of GREYBULL ARPT

Thunderstorm Wind63 mph (55 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind64 mph (56 knots, measured gust)

5 miles E of KANE

Thunderstorm Wind64 mph (56 knots, measured gust)

At COWLEY ARPT

Thunderstorm Wind70 mph (61 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind59 mph (51 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind66 mph (57 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind58 mph (50 knots, measured gust)

At GREYBULL ARPT

Hail1.00 in, quarter size

3 miles N of BASIN

Thunderstorm Wind59 mph (51 knots, measured gust)

At GREYBULL ARPT

Thunderstorm Wind79 mph (69 knots, measured gust)

At GREYBULL ARPT. Damage estimate: $25 thousand

The 25 events above are the newest in the NCEI record. A place is the text of the NCEI record: a distance and a direction from a reference place. Wind speed is in miles per hour, with the knots that NCEI gives. The site does not show a place text that names a private property or reads as a person. Download these events (CSV)

Storm events on record for Big Horn County by year, 1950 to 2026
DecadeYear that ends in 0Year that ends in 1Year that ends in 2Year that ends in 3Year that ends in 4Year that ends in 5Year that ends in 6Year that ends in 7Year that ends in 8Year that ends in 9All
1950s00000000123
1960s01201001005
1970s00003211209
1980s02003101119
1990s2521021105129
2000s37701611431860
2010s10901599579578
2020s3294740 (part of the year)29

A darker cell has a larger count. The number is in each cell.

NCEI recorded tornado events from 1950, and hail and thunderstorm wind events from 1955. It recorded all event types from 1996. A count before 1996 has fewer event types.

FEMA disaster declarations

FEMA has 4 disaster declarations on record for Big Horn County from 1964 through 1 Oct 2026. The newest is DR-4535: COVID-19 PANDEMIC.

Disaster declarations that name Big Horn County (OpenFEMA, through 1 Oct 2026)
DeclaredNumberTypeIncident typeTitle in the FEMA recordAssistance
DR-4535Major disasterBiologicalCOVID-19 PANDEMICIndividual, Public
EM-3479EmergencyBiologicalCOVID-19Public
DR-4007Major disasterSevere StormSEVERE STORMS, FLOODING, AND LANDSLIDESPublic
DR-557Major disasterFloodSEVERE STORMS, FLOODING & MUDSLIDESIndividual, Public

DR is a major disaster declaration. EM is an emergency declaration. FM is a fire management assistance declaration. A declaration for the whole state is on the Wyoming page. What a disaster declaration is

The dataset includes declared recovery programs and geographic areas (county not available before 1964; Fire Management records are considered partial due to historical nature of the dataset).

The words of the agency. Source: FEMA, OpenFEMA Dataset "Disaster Declarations Summaries - v2", copied on . The page gives: last data refresh 2026-10-01.

Flood insurance claims (NFIP)

OpenFEMA has 9 NFIP claims on record for Big Horn County from 1978 through 8 Sep 2026.

The NFIP paid $247,622 on 7 claims.

FEMA counts 16 residential policies in force on 3 Aug 2026. The site gives a rate for each 1,000 policies only from 100 policies, because one claim changes a smaller rate too much.

NFIP claims in Big Horn County by year of loss, 1978 to 2026
DecadeYear that ends in 0Year that ends in 1Year that ends in 2Year that ends in 3Year that ends in 4Year that ends in 5Year that ends in 6Year that ends in 7Year that ends in 8Year that ends in 9All
1970s101
1980s00000000000
1990s00000001001
2000s00000000000
2010s02003100006
2020s0000100 (part of the year)1

A darker cell has a larger count. The number is in each cell.

NFIP claims by year of loss with the amount paid: 6 years
NFIP claims in Big Horn County by year of loss, with the amount paid (OpenFEMA, through 8 Sep 2026)
Year of lossClaimsClaims with a paymentAmount paid
20241not shownnot shown
20151not shownnot shown
20143not shownnot shown
20112not shownnot shown
19971not shownnot shown
19781not shownnot shown

A year with fewer than 5 claims shows the count of claims and no amount. A year with 1 to 4 claims with a payment shows no amount either. Such an amount could point to one property. The amount is the sum of the building, contents and increased cost of compliance payments. How FEMA redacts NFIP claims

This dataset is not intended to be an official federal report, and should not be considered an official federal report.

Note, the County Code field may not reflect the individual county the property is located as projects can be associated with more than one county

The words of the agency. Source: FEMA, OpenFEMA Dataset "NFIP Redacted Claims - v3", copied on . The page gives: last data refresh 2026-09-09.

FEMA cannot verify the quality and/or timeliness of any data or any analysis derived therefrom after the data has been retrieved from FEMA.gov.

The words of the agency. Source: FEMA, OpenFEMA Terms and Conditions, copied on . The page gives: last updated 2025-01-22.

National Risk Index

Risk Index rating
Very Low
Risk Index score
31.1 of 100
Expected Annual Loss rating
Very Low
Expected Annual Loss
$8.9 million
Social Vulnerability rating
Relatively Moderate
Community Resilience rating
Very Low
National Risk Index of Big Horn County by hazard type (FEMA, December 2025 release)
Hazard typeRisk Index ratingExpected Annual Loss
AvalancheVery Low$110
Cold waveRelatively Low$1,134,455
DroughtRelatively Low$53,957
EarthquakeRelatively Low$424,845
HailVery Low$87,805
Heat waveVery Low$12,499
Ice stormVery Low$3,946
Inland floodingRelatively Low$6,167,310
LandslideRelatively High$493,309
LightningRelatively Low$125,761
Strong windVery Low$79,985
TornadoVery Low$155,238
Volcanic activityVery Low$3
WildfireVery Low$80,910
Winter weatherRelatively Low$48,923

The National Risk Index dataset leverages available source data for natural hazard and community risk factors to develop a baseline relative risk measurement for each United States county and Census tract.

The rating is a qualitative categorization that describes the community in comparison to all other communities at the same level, ranging from “Very Low” to “Very High.”

The National Risk Index data are meant for planning purposes only.

The words of the agency. Source: FEMA, National Risk Index Data: Frequently Asked Questions (December 2025, v1.20), copied on .

The labels and the ratings are those of FEMA. Expected Annual Loss is a figure for a whole county. It is not a figure for a property. How to read the National Risk Index

Tropical storm and hurricane tracks

The HURDAT2 record of the National Hurricane Center goes through the 2025 season. It has no track at tropical storm strength within 100 miles of the centre point of Big Horn County.

ZIP Codes, cities and towns of Big Horn County

A city or town has no page of its own. This page is the record for the whole county, which has these places:

  • Basin
  • Burlington
  • Byron
  • Cowley
  • Deaver
  • Frannie
  • Greybull
  • Hyattville
  • Lovell
  • Manderson
  • Shell

Official channels

These links open the pages of the agencies. The site checked the links on .

Cite this page

County Hazards. "Big Horn County, Wyoming: storm events, disaster declarations and flood insurance claims on record". https://countyhazards.com/county/wy/big-horn/. Data: NOAA NCEI Storm Events Database through 30 Jun 2026; FEMA OpenFEMA disaster declarations through 1 Oct 2026; FEMA OpenFEMA NFIP claims through 8 Sep 2026. Page made on .

Where the data comes from

  • Storm events: NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026.
  • Disaster declarations: OpenFEMA Disaster Declarations Summaries, read on 1 Oct 2026.
  • NFIP claims: OpenFEMA NFIP Claims, as of 8 Sep 2026. Multiple-loss properties: 2 Aug 2026. Policies in force: 3 Aug 2026.
  • National Risk Index: FEMA, December 2025 release. Storm tracks: NHC HURDAT2 through the 2025 season.
  • Residents, area, places and adjacent counties: US Census Bureau, 2021 vintage.

How the counts are made · Corrections · Hazards in all states: hail, tornado, flood, wind, winter

Questions

How many tornado events are on record for Big Horn County?
NCEI has 33 tornado events on record for Big Horn County from 1950 through 30 Jun 2026. 7 events have a rating of EF2 or F2, or a higher rating.
How large is the hail on record for Big Horn County?
NCEI has 62 hail events on record from 1955 through 30 Jun 2026. 16 events have a hail size of 1.75 inches or more. NCEI names 1.75 inches a golf ball.
Which month has the most storm events on record for Big Horn County?
June has 108 of the 222 storm events on record from 1950 through 30 Jun 2026.
How many NFIP claims are there for each 1,000 policies in force in Big Horn County?
FEMA counts 16 residential policies in force on 3 Aug 2026. The site gives a rate for each 1,000 policies only from 100 policies, because one claim changes a smaller rate too much.