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Idaho · FEMA + NOAA + National Risk Index

Custer County, ID

7 FEMA disaster declarations (1984-2020), with a FEMA National Risk Index rating of Relatively Low. Most common hazard: Biological.

7
FEMA declarations
5
Major disasters
52
NRI risk · Relatively Low
Biological
Top hazard

The verdict

Start with the local benchmark for Custer County: 7 FEMA declaration records are 16% below the Idaho county mean, even though the count is higher than 4% of counties in the national registry. On FEMA's distinct National Risk Index model, which combines expected loss with vulnerability and resilience, the county ranks in the riskiest 48%.

Riskiest 48%
of U.S. counties for FEMA National Risk Index score
Relatively Low
FEMA National Risk Index rating
7
FEMA declarations vs 21 national county avg
1
NFIP flood insurance claims filed

FEMA's National Risk Index and its declaration registry are separate measures. This county's registry includes Major Disaster (DR) and Emergency (EM) records; an EM authorizes a narrower set of federal assistance than a DR.

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FEMA OpenFEMA declaration desk

County FIPS 16037 · Custer County 7 declarations · rank 3140/3,266

DECL-LIGHT · MAJOR-MID · RANK-LOWER · PHOTO-FINISH · NRI-LOW · ACT-MODERATE · TYPE-LEAD · VS-ST-BELOW

  • DECL-LIGHT 7
  • MAJOR-MID 71%
  • RANK-LOWER #3,140
  • PHOTO-FINISH Clinton
  • NRI-LOW 52
  • ACT-MODERATE Moderate
  • TYPE-LEAD Biological
  • VS-ST-BELOW -16%

Nearest declaration peer: Clinton, IL (0 declaration gap)

FEMA Disaster Declarations Summaries v2 filing stamps for this county register. Read with this county → · Idaho state profile

Custer County among counties with fewer federal records

FEMA declaration records among Custer County and nearest peers by total count

declarations

What this shows Custer County carries 7 FEMA declaration records, ranked 3140 of 3,266 counties in this registry.

Source FEMA OpenFEMA Disaster Declarations Summaries v2 As of 2026-08-25

Custer County versus quieter counties in this dataset

Custer County among lower-declaration counties nationally

FEMA disaster declarations, all-time · Custer County

7 4th percentile higher than 4% of 3,266 counties

This county 0 90 all U.S. counties FEMA tracks, bucketed by value

Each bar is a band; taller bars hold more counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source FEMA Disaster Declarations Summaries v2 · 2026-08-25

Custer County's FEMA Risk Index score

0/100100/100Idaho avg39/10052.4/100
FEMA National Risk Index composite score vs. the Idaho county average

Which hazard drives modeled loss here?

FEMA's modeled annual dollar loss for Custer County is led by Riverine Flooding (about $5.1M Expected Annual Loss, Historical Loss Ratio Relatively High), while Landslide carries the highest National Risk Index rating (Relatively High). EAL and risk score use different inputs; they need not agree.

Source: FEMA National Risk Index (December 2025 release) - Expected Annual Loss vs composite risk rating by hazard.

What does Custer County's hazard record show?

FEMA National Risk Index

This county carries a high composite score on FEMA's National Risk Index, 52.4/100, rated Relatively Low. Its Expected Annual Loss rating is Very Low (roughly $10.6M in annualized losses), and a Very High social-vulnerability profile combined with Very Low community resilience shapes how much of that raw exposure becomes realized harm. Of the 18 hazards FEMA models, Landslide stands out as the sharpest exposure here, rated Relatively High. FEMA's modeled frequency puts that hazard at an average of 7.3 times per year here.

Reading the federal records together

This county has a small entry in FEMA's NFIP paid-claims table: 1 claim and $1.9K paid in total. PlainHazard calls 1-49 claims a light registry record, a label for this dataset rather than a finding that flood exposure is low. A short claims history can also reflect insurance take-up, the period covered, or losses that were never insured.

Start with the state benchmark: a Idaho county averages 8.3 federal declaration records, while Custer County has 7. The gap is 16% below that mean. Fewer entries indicate a quieter history of recorded federal actions, not immunity from a hazard and not a prediction about what happens next.

49 /100

Historical Activity Index

Moderate historical activity

Custer County, ID · PlainHazard-derived composite from federal records

This 0–100 index is an explicit PlainHazard composite from FEMA declaration history only on the county surface (this DB has no county-level NOAA damage row) . It is not FEMA's National Risk Index, not a forecast, and not a safety, insurance, or preparedness rating. Open the calculator · Methodology

FEMA Declarations (1953–present) Low
5/30

7 OpenFEMA declarations, full ingest window (0.3x national county average)

County Disaster Density Moderate
11/25

7 declarations (0.8x state county average of 8)

Major Disaster Share High
18/25

5 of 7 declarations are major disasters (71%)

Hazard Diversity Very High
15/20

6 different disaster types declared in Custer County

FEMA NRI 8-hazard radar - Custer County

Custer County NRI risk profile 8-axis FEMA National Risk Index radar showing per-hazard scores for Earthquake 25, Flood 25, Hurricane 0, Tornado 8, Wildfire 25, Drought 8, Heat Wave 8, Winter Storm 25. The simple mean of these eight displayed scores is 16 of 100. Earthquake Flood Hurricane Tornado Wildfire Drought Heat Wave Winter Storm 16 8-hazard mean
Custer County NRI risk profile FIPS 16037 · displayed-hazard mean 16/100
How to read this radar

Each axis: NRI risk rating (Very Low-Very High) on a 0-100 scale. Rounder = broad exposure; spiky = one or two hazards dominate.

FEMA Records

7

Low volume

Major Disaster share

71%

Major-heavy

NRI risk score

52

Relatively Low

Source: FEMA National Risk Index Per-county per-hazard ratings, December 2025 release

How often does each hazard strike Custer County?

FEMA's National Risk Index models a historical event count and an annualized frequency for each hazard type. Most hazards are expressed as modeled occurrences per year; FEMA expresses drought and heat-wave frequency as event-days per year. These modeled frequencies are not forecasts.

Hazard NRI Risk Rating Recurrence
Landslide Relatively High an average of 7.3 times per year
Avalanche Very High roughly once every 4 years
Wildfire Relatively Low roughly once every 796 years
Earthquake Relatively Low roughly once every 36 years
Riverine Flooding Relatively Low roughly once every 2 years
Winter Weather Relatively Low an average of 20 times per year
Lightning Relatively Low an average of 28 times per year
Cold Wave Relatively Low roughly once every 1 years
Volcanic Activity Very Low roughly once every 1,667 years
Heat Wave Very Low 0.3 modeled event-days per year
Strong Wind Very Low roughly once every 4 years
Drought Very Low 94 modeled event-days per year
Ice Storm Very Low roughly once every 67 years
Tornado Very Low roughly once every 8 years
Hail Very Low roughly once every 13 years

Source: FEMA National Risk Index Modeled annualized frequency; drought and heat wave use event-days/year, December 2025 release

Disaster Types

Biological 2
Flood 1
Hurricane 1
Fire 1
Severe Storm 1
Earthquake 1

What Biological declarations mean here

Biological is the most frequent declaration type on Custer County's record, 29% of its declarations. In practice this category is dominated by the COVID-19 declarations of 2020, which were issued across every US state and territory rather than in response to any local hazard event.

This has a direct consequence for how Custer County's number should be read. Because those declarations reached essentially every county in the country, they raise every county's total by a similar amount and tell you nothing about local hazard exposure. A county whose record is led by Biological declarations is, in most cases, a county with a genuinely quiet weather-hazard history, the pandemic records are simply the largest thing in an otherwise short list.

Declaration counts describe past federal action. They are a record of what was declared, not a forecast of future hazard probability.

Declaration Types

What DR / EM / FM mean

FEMA categorizes declarations as Major Disasters (DR), Emergencies (EM), or Fire Management Assistance (FM).

Major Disaster - 5 71.4%

of all 7 declarations

Emergency - 2 28.6%

of all 7 declarations

FEMA Declarations Timeline

Year Declarations
2020 2
2017 1
2005 1
2000 1
1997 1
1984 1

Disaster Declarations

How the 7 FEMA declarations break into federal action codes (DR / EM / FM). Same DISTINCT grain as the table below.

Download these 7 declarations as CSV . FEMA source data is public domain; our derived presentation is CC0.

DR# Title Type Incident Date
4534 COVID-19 PANDEMIC DR Biological 2020-04-09
3467 COVID-19 EM Biological 2020-03-13
4333 FLOODING, LANDSLIDES, AND MUDSLIDES DR Flood 2017-08-27
3244 HURRICANE KATRINA EM Hurricane 2005-09-13
1341 WILDFIRES DR Fire 2000-09-01
1177 SEVERE STORMS, SNOWMELT, LAND/MUD SLIDES, FLOODING DR Severe Storm 1997-06-13
694 EARTHQUAKE DR Earthquake 1983-11-18

Storm Events in Idaho

Statewide NOAA context only. PlainHazard does not currently attribute these state totals to Custer County.

Storm Type Events Fatalities Injuries Property Damage
Heavy Snow 1,495 1 13 $100.9M
Thunderstorm Wind 1,087 9 26 $3.6M
Winter Storm 492 4 15 $1.0M
High Wind 396 4 6 $10.6M
Winter Weather 297 10 15 $1.7M

Source: NOAA Storm Events Database State-level aggregated data, 2015-2025

NFIP Flood Insurance Claims

Total Claims

1

Total Paid

$1.9K

Avg Per Claim

$1.9K

Source: FEMA National Flood Insurance Program (NFIP) OpenFEMA Claims Data

FEMA National Risk Index

Overall Risk

Relatively Low

Score: 52.4/100

Expected Annual Loss

Very Low

$10.6M/year

Social Vulnerability

Very High

Community Resilience

Very Low

Hazard Risk Breakdown

Landslide Relatively High
Avalanche Very High
Wildfire Relatively Low
Earthquake Relatively Low
Riverine Flooding Relatively Low
Winter Weather Relatively Low
Lightning Relatively Low
Cold Wave Relatively Low
Volcanic Activity Very Low
Heat Wave Very Low
Strong Wind Very Low
Drought Very Low
Ice Storm Very Low
Tornado Very Low
Hail Very Low

Source: FEMA National Risk Index (NRI) Ratings reflect relative scores among all US counties. Data: hazards.fema.gov/nri

The model's sharpest exposure here: Landslide

Landslide risk is a function of slope, soil and water, so it is usually a SECOND-ORDER hazard: it is triggered by the rainfall, snowmelt, wildfire burn scars or seismic shaking that came first. That is why a county can carry high landslide exposure whose realized damage is recorded under a flood or storm declaration instead.

Worth noting for Custer County: the model and the federal record do NOT point at the same hazard. Landslide carries the highest modeled rating (Relatively High), while the county's declaration history is led by Biological. That is not a contradiction, the two measure genuinely different things. Declarations record federal ACTION, which requires damage costly enough to exceed state and local capacity; the Risk Index models EXPECTED annual loss across all 18 hazards whether or not any declaration ever followed. A hazard can be the county's largest modeled exposure and never once have driven a declaration.

National Risk Index ratings are modeled estimates of expected annual loss, not predictions of what will happen in any given year.

Data-matched county comparisons

Custer County's closest FEMA peer: Perry County, IL

Comparisons use published FEMA declaration fields plus the National Risk Index composite for Custer County. Record similarity, not a safety rating.

How these peers are chosen

Cohort: Published U.S. county equivalents outside the source state or territory. Each metric keeps six ETL candidates; three unique destinations are shown after de-duplicating across axes. Declaration-volume ranking combines count and Major-disaster share and prefers a different leading incident type; Major-share ranks the Major fraction adjusted for volume; NRI ranks the modeled composite score only.

Retained FEMA snapshot feed for Custer County - capture-dated entries only.

Compare beyond this state

Nationwide peers by NRI score & FEMA declaration volume

Two PlainHazard-derived comparison paths for Custer County: nearest out-of-state National Risk Index composite and nearest FEMA declaration count (floor ≥5 records). Record similarity only, not a forecast of the next hazard.

Further reading for this county

Understanding disaster data

FEMA's National Risk Index flags Landslide as the top modeled exposure here (Relatively High); the guide explains how that model differs from declaration counts.

More PlainHazard guides

Frequently Asked Questions

What is the most common disaster type in Custer County?
The most common disaster type in Custer County is Biological, with 2 declarations. Other disaster types include Flood (1), Hurricane (1), Fire (1).
How does Custer County's FEMA declaration record compare with the Idaho average?
The typical Idaho county has 8.3 FEMA declaration records; Custer County has 7, or 16% fewer. Against the national county mean of 20.7, this county's total is 66% lower. The comparison is historical and says nothing about the probability of a future event.
How many major FEMA disaster declarations has Custer County received?
Custer County has received 5 major disaster declarations, representing 71% of all 7 disaster declarations.
How many flood insurance claims has Custer County filed?
Custer County has 1 National Flood Insurance Program (NFIP) claims totaling $1.9K in payments, with an average of $1.9K per claim.
Does FEMA's top risk-rated hazard match the highest Expected Annual Loss in Custer County?
No. In Custer County, Landslide has the highest National Risk Index rating (Relatively High), while Riverine Flooding leads Expected Annual Loss at about $5.1M. FEMA's risk score and dollar-loss model use different inputs, so the leaders often differ.
What was the worst year for disasters in Custer County?
The most active year for disaster declarations in Custer County was 2020, with 2 declarations. The county has FEMA disaster data spanning 1984 to 2020.
What is the FEMA National Risk Index score for Custer County?
According to the FEMA National Risk Index, Custer County, Idaho has an overall risk score of 52.4 out of 100 (Relatively Low). The county's social vulnerability rating is Very High and community resilience is Very Low. The Expected Annual Loss (EAL) score is Very Low, representing $10.6M in annualized losses.
Which natural hazard poses the greatest risk to Custer County?
Based on FEMA NRI data, the highest-risk natural hazard in Custer County as of the latest release is Landslide (risk rating: Relatively High). Other significant hazards include Avalanche (Very High) and Wildfire (Relatively Low). FEMA's modeled event frequency puts landslide here at an average of 7.3 times per year. These scores are based on FEMA's analysis of historical event frequency, exposed assets, and community vulnerability.
Data Sources & Methodology

Disaster declaration data comes from the FEMA OpenFEMA Disaster Declarations Summaries v2 API, which includes all federally declared disasters, emergencies, and fire management assistance grants.

Storm event data is sourced from the NOAA Storm Events Database (2015-2025), which tracks significant weather events including thunderstorms, tornadoes, floods, and winter storms.

Flood insurance data comes from the FEMA National Flood Insurance Program (NFIP) OpenFEMA claims dataset.

This data is provided for informational purposes only. FEMA disaster declarations represent federal response actions and may not capture all local emergencies or weather events.

FEMA OpenFEMA declarations + NRI for Custer County · vintage 2026-08-25 · Methodology · Idaho profile · Verify with FEMA OpenFEMA · Verify with NOAA Storm Events