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FloodWY

Wyoming Flood Hazard Profile

Hazard Data · Model Version 2.5

Overview

Wyoming's flood record is short by national standards — OpenFEMA lists 7 federal flood declarations between 1963 and 2023 — but the exposure is concentrated rather than absent. Snowmelt-driven flooding on the Bighorn, Wind River and Green River systems arrives in a narrow seasonal window, and the counties affected have among the smallest response capacities in the country, so a single event consumes a disproportionate share of local capability.

In the Historical Record

7
federal disaster declarations (1963–2023)
FEMA OpenFEMA Disaster Declarations
557
NFIP flood insurance claims paid
FEMA OpenFEMA NfipClaims, 1978–2024

Counted from the records this platform holds. A figure is shown only where the underlying dataset could be read.

County by County in Wyoming

What federal records show has happened in each county: storms, disaster declarations and flood insurance claims. The counties below have the longest NOAA storm records in Wyoming.

All Wyoming counties

Notable Historical Events

1June 2023 flooding — FEMA DR-4739, the most recent declaration
2June 2017 flooding — FEMA DR-4327
3June 2010 flooding — FEMA DR-1923

Hazard Scoring Approach

Calchis computes a Calchis Hazard Score (0–10) for flood hazard at any US address. The score is composed of weighted sub-components derived from federal data sources and published research. All score components are transparent and returned in API responses.

These are hazard scores — physical intensity likelihood only. They do not include property exposure or vulnerability data. We never call a hazard score a risk score. See the full methodology for scoring details.

Analyze Your Address

Enter any Wyoming address to see location-specific flood hazard scoring with full methodology transparency.

Open Live Map — Wyoming

Data Sources

FEMA Disaster Declarations (OpenFEMA)www.fema.gov
NOAA NWPS River Gaugeswater.noaa.gov
USGS StreamStatsstreamstats.usgs.gov

Related

Monitoring flood exposure in Wyoming?

This page is a state-level profile. Calchis scores individual addresses, tracks live flood events against your own locations, and alerts you when one approaches them.

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Calchis Hazard Score — derived from federal and academic sources listed above. Property exposure data not included. Not a substitute for professional actuarial assessment. Decision-support intelligence — not a primary alerting or dispatch system. Verify against official sources.