FEMA Records
31
High volume
New York · FEMA + NOAA + National Risk Index
Nassau County, NY
31 FEMA disaster declarations (1965-2024), with a FEMA National Risk Index rating of Relatively High. Most common hazard: Hurricane.
- 31
- FEMA declarations
- 21
- Major disasters
- 97
- NRI risk · Relatively High
- Hurricane
- Top hazard
The verdict
Two federal records point in the busier direction for Nassau County. Its 31 FEMA declarations are 26% above the New York county mean and exceed the count for 88% of the 3,266 counties in this registry. Separately, FEMA's National Risk Index places it in the riskiest 3%, based on modeled expected annual loss, social vulnerability, and community resilience.
- Riskiest 3%
- of U.S. counties for FEMA National Risk Index score
- Relatively High
- FEMA National Risk Index rating
- 31
- FEMA declarations vs 21 national county avg
- 51,518
- 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.
FEMA OpenFEMA declaration desk
County FIPS 36059 · Nassau County 31 declarations · rank 363/3,266
DECL-HEAVY · MAJOR-MID · RANK-MID · PHOTO-FINISH · NRI-HIGH · ACT-HIGH · TYPE-LEAD · VS-ST-ABOVE
- DECL-HEAVY 31
- MAJOR-MID 68%
- RANK-MID #363
- PHOTO-FINISH Galveston
- NRI-HIGH 97
- ACT-HIGH High
- TYPE-LEAD Hurricane
- VS-ST-ABOVE +26%
Nearest declaration peer: Galveston, TX (0 declaration gap)
FEMA Disaster Declarations Summaries v2 filing stamps for this county register. Read with this county → · New York state profile
Nassau County among high-volume declaration counties
FEMA declaration records among Nassau County and nearest peers by total count
- Los Angeles · largest
Los Angeles · largest
88 declarations
- Galveston · near 31
Galveston · near
31 declarations
- Nassau · this county 31
Nassau · this county
31 declarations
- Orange · near 31
Orange · near
31 declarations
- Woodward · near 31
Woodward · near
31 declarations
- Ujelang · smallest 1
Ujelang · smallest
1 declarations
What this shows Nassau County carries 31 FEMA declaration records, ranked 363 of 3,266 counties in this registry.
Where Nassau County ranks in the national declaration registry
Nassau County vs. high-volume counties in this registry
FEMA disaster declarations, all-time · Nassau County
31 Top 12% higher than 88% of 3,266 counties
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
Nassau County's FEMA Risk Index score
Which hazard drives modeled loss here?
FEMA's modeled annual dollar loss for Nassau County is led by Riverine Flooding (about $183.9M Expected Annual Loss, Historical Loss Ratio Very Low), while Winter Weather carries the highest National Risk Index rating (Very 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 Nassau County's hazard record show?
Reading the federal records together
FEMA's NFIP table contains a substantial paid-claim history for this county: 51,518 claims and $2.3B in payments. PlainHazard labels 500 or more claims a heavy registry record; that is a reporting bucket, not an official FEMA risk grade. The average paid claim was $44.3K. NFIP totals exclude uninsured flood losses and do not measure how many properties currently carry a policy.
The declaration register points in the busier direction. Nassau County's 31 federal records stand 26% above the New York county mean of 24.5. That comparison describes how often federal action was recorded, including any Major Disaster, Emergency, and Fire Management entries shown on this page; it does not convert the count into future probability.
FEMA National Risk Index
This county sits among the highest-risk counties nationally on FEMA's National Risk Index, a composite score of 97.1/100 (Relatively High). Expected Annual Loss is rated Relatively High (roughly $298.6M in annualized losses). Social vulnerability reads Relatively Low and community resilience Very High, both critical modifiers of realized harm here. Of the 18 hazards FEMA models, Winter Weather stands out as the sharpest exposure here, rated Very High. FEMA's modeled frequency puts that hazard at an average of 9.8 times per year here, based on 122 historical events on record.
75 /100
Historical Activity Index
Very High historical activity
Nassau County, NY · 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) High
22/30
31 OpenFEMA declarations, full ingest window (1.5x national county average)
County Disaster Density High
16/25
31 declarations (1.3x state county average of 25)
Major Disaster Share High
17/25
21 of 31 declarations are major disasters (68%)
Hazard Diversity Very High
20/20
8 different disaster types declared in Nassau County
FEMA NRI 8-hazard radar - Nassau County
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.
Major Disaster share
68%
Major-heavy
NRI risk score
97
Relatively High
Source: FEMA National Risk Index Per-county per-hazard ratings, December 2025 release
How often does each hazard strike Nassau 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 |
|---|---|---|
| Winter Weather | Very High | an average of 9.8 times per year |
| Ice Storm | Very High | roughly once every 1 years |
| Coastal Flooding | Very High | an average of 3.8 times per year |
| Riverine Flooding | Relatively High | an average of 3.3 times per year |
| Lightning | Very High | an average of 27 times per year |
| Strong Wind | Relatively High | an average of 4.9 times per year |
| Earthquake | Relatively Moderate | roughly once every 529 years |
| Heat Wave | Relatively Moderate | 5.8 modeled event-days per year |
| Hurricane | Relatively High | roughly once every 6 years |
| Cold Wave | Relatively High | roughly once every 2 years |
| Tornado | Relatively Moderate | roughly once every 8 years |
| Landslide | Relatively Low | roughly once every 13 years |
| Wildfire | Very Low | roughly once every 8,099 years |
| Hail | Very Low | an average of 1.7 times per year |
| Drought | Very Low | 0.8 modeled event-days per year |
Source: FEMA National Risk Index Modeled annualized frequency; drought and heat wave use event-days/year, December 2025 release
Disaster Types
Hurricane 12
Severe Storm 6
Flood 4
Snowstorm 3
Biological 2
Other 2
Fire 1
Drought 1
What Hurricane declarations mean here
Hurricane is the most frequent declaration type on Nassau County's federal record, 39% of its declarations. Atlantic tropical systems run on a defined season, 1 June to 30 November, with most activity concentrated between August and October; Pacific and territorial basins run on their own calendars. A single named storm routinely produces one declaration number covering a long corridor of counties at once, well inland as well as on the coast, which is why an affected county's count can jump by several in one year without several separate events having occurred.
One practical distinction matters when reading these records: a tropical declaration usually bundles wind, storm surge and inland rainfall flooding under a single incident, but the insurance behind them is split. Wind damage falls to property insurers, while flood and surge damage is covered only under a separate National Flood Insurance Program policy. That is why a county can show heavy declaration activity and a comparatively small NFIP claims record, or the reverse.
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 - 21 67.7%
of all 31 declarations
Emergency - 10 32.3%
of all 31 declarations
FEMA Declarations Timeline
| Year | Declarations | |
|---|---|---|
| 2024 | 1 | |
| 2021 | 4 | |
| 2020 | 2 | |
| 2013 | 2 | |
| 2011 | 3 | |
| 2010 | 2 | |
| 2005 | 1 | |
| 2004 | 1 | |
| 2003 | 2 | |
| 2001 | 2 | |
| 1999 | 1 | |
| 1998 | 1 | |
| 1997 | 1 | |
| 1996 | 1 | |
| 1993 | 2 | |
Show 5 earlier declaration years
| 1986 | 1 | |
| 1984 | 1 | |
| 1976 | 1 | |
| 1971 | 1 | |
| 1965 | 1 | |
Disaster Declarations
How the 31 FEMA declarations break into federal action codes (DR / EM / FM). Same DISTINCT grain as the table below.
Download these 31 declarations as CSV . FEMA source data is public domain; our derived presentation is CC0.
| DR# | Title | Type | Incident | Date |
|---|---|---|---|---|
| 4755 | SEVERE STORM AND FLOODING | DR | Flood | 2024-01-30 |
| 4615 | REMNANTS OF HURRICANE IDA | DR | Hurricane | 2021-09-05 |
| 3572 | REMNANTS OF HURRICANE IDA | EM | Hurricane | 2021-09-02 |
| 3565 | HURRICANE HENRI | EM | Hurricane | 2021-08-22 |
| 4567 | TROPICAL STORM ISAIAS | DR | Hurricane | 2020-10-02 |
| 4480 | COVID-19 PANDEMIC | DR | Biological | 2020-03-20 |
| 3434 | COVID-19 | EM | Biological | 2020-03-13 |
| 4085 | HURRICANE SANDY | DR | Hurricane | 2012-10-30 |
| 3351 | HURRICANE SANDY | EM | Hurricane | 2012-10-28 |
| 4020 | HURRICANE IRENE | DR | Hurricane | 2011-08-31 |
| 3328 | HURRICANE IRENE | EM | Hurricane | 2011-08-26 |
| 1957 | SEVERE WINTER STORM AND SNOWSTORM | DR | Severe Storm | 2011-02-18 |
| 1899 | SEVERE STORMS AND FLOODING | DR | Severe Storm | 2010-04-16 |
| 1869 | SEVERE STORMS AND FLOODING ASSOC W TD IDA & NOR'EASTER | DR | Severe Storm | 2009-12-31 |
| 3262 | HURRICANE KATRINA EVACUATION | EM | Hurricane | 2005-09-30 |
| 1534 | SEVERE STORMS AND FLOODING | DR | Severe Storm | 2004-08-03 |
| 3186 | POWER OUTAGE | EM | Other | 2003-08-23 |
| 3184 | SNOW | EM | Snowstorm | 2003-03-27 |
| 1391 | FIRES AND EXPLOSIONS | DR | Fire | 2001-09-11 |
| 3155 | WEST NILE VIRUS | EM | Other | 2000-10-11 |
Show 11 earlier declaration records
| DR# | Title | Type | Incident | Date |
|---|---|---|---|---|
| 1296 | HURRICANE FLOYD MAJOR DISASTER DECLARATIONS | DR | Hurricane | 1999-09-19 |
| 1244 | NY - SEVERE WX, SEPT 7, 1998 | DR | Severe Storm | 1998-09-11 |
| 1146 | SEVERE STORMS, FLOODING, HEAVY RAINS, HIGH WINDS | DR | Severe Storm | 1996-11-19 |
| 1083 | BLIZZARD OF 96 (SEVERE SNOW STORM) | DR | Snowstorm | 1996-01-12 |
| 3107 | SEVERE BLIZZARD | EM | Snowstorm | 1993-03-17 |
| 974 | COASTAL STORM, HIGH TIDES, HEAVY RAIN, & FLOODING | DR | Flood | 1992-12-21 |
| 750 | HURRICANE GLORIA | DR | Hurricane | 1985-10-18 |
| 702 | COASTAL STORMS & FLOODING | DR | Flood | 1984-04-17 |
| 520 | HURRICANE BELLE | DR | Hurricane | 1976-09-03 |
| 311 | SEVERE STORMS & FLOODING | DR | Flood | 1971-09-13 |
| 204 | WATER SHORTAGE | DR | Drought | 1965-08-18 |
Storm Events in New York
Statewide NOAA context only. PlainHazard does not currently attribute these state totals to Nassau County.
| Storm Type | Events | Fatalities | Injuries | Property Damage |
|---|---|---|---|---|
| Thunderstorm Wind | 8,295 | 6 | 45 | $45.0M |
| Winter Weather | 2,261 | 7 | 17 | $705.5K |
| Flash Flood | 1,775 | 23 | 3 | $674.3M |
| Strong Wind | 1,399 | 2 | 12 | $9.2M |
| Winter Storm | 1,228 | 13 | 2 | $4.9M |
Source: NOAA Storm Events Database State-level aggregated data, 2015-2025
NFIP Flood Insurance Claims
Total Claims
51,518
Total Paid
$2.3B
Avg Per Claim
$44.3K
Source: FEMA National Flood Insurance Program (NFIP) OpenFEMA Claims Data
FEMA National Risk Index
Overall Risk
Relatively High
Score: 97.1/100
Expected Annual Loss
Relatively High
$298.6M/year
Social Vulnerability
Relatively Low
Community Resilience
Very High
Hazard Risk Breakdown
Winter Weather Very High
Ice Storm Very High
Coastal Flooding Very High
Riverine Flooding Relatively High
Lightning Very High
Strong Wind Relatively High
Earthquake Relatively Moderate
Heat Wave Relatively Moderate
Hurricane Relatively High
Cold Wave Relatively High
Tornado Relatively Moderate
Landslide Relatively Low
Wildfire Very Low
Hail Very Low
Drought 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: Winter Weather
Winter Weather in the model means the accumulation of snow and cold that disrupts rather than destroys: road closures, roof loads, burst pipes and lost heating. Its costs land heavily on transport and on households least able to absorb an interruption.
Worth noting for Nassau County: the model and the federal record do NOT point at the same hazard. Winter Weather carries the highest modeled rating (Very High), while the county's declaration history is led by Hurricane. 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
Nassau County's closest FEMA peer: Yazoo County, MS
Comparisons use published FEMA declaration fields plus the National Risk Index composite for Nassau County. Record similarity, not a safety rating.
Closest declaration profiles
Nassau County shows 31 FEMA declarations, led by Hurricane.
Similar Major-disaster share
Nassau County: 21 of 31 of its declarations are Major.
Similar modeled NRI score
Nassau County: NRI composite 97.1 (Relatively High).
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 Nassau County - capture-dated entries only.
Compare beyond this state
Nationwide peers by NRI score & FEMA declaration volume
Two PlainHazard-derived comparison paths for Nassau 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.
Similar NRI composite
Nearest out-of-state counties by FEMA NRI score. This county: 97.1 (Relatively High).
Similar declaration volume
Nearest out-of-state counties by FEMA declaration count. This county: 31. NRI peers are excluded so the two link sets stay distinct.
Further reading for this county
Understanding disaster data
Nassau County's NFIP claims file (51,518 claims) and FEMA declaration history measure different federal records - this guide separates them from modeled NRI risk.
More PlainHazard guides
- Most disaster-prone counties - U.S. counties ranked by FEMA declaration totals.
- Understanding disaster data - declarations vs storm events vs NRI scores.
- Preparing for natural disasters - household checklist (not county-specific advice).
Frequently Asked Questions
What is the most common disaster type in Nassau County?
The most common disaster type in Nassau County is Hurricane, with 12 declarations. Other disaster types include Severe Storm (6), Flood (4), Snowstorm (3).
How does Nassau County's FEMA declaration record compare with the New York average?
FEMA lists 31 declaration records for Nassau County. That is 26% above the New York county mean of 24.5. Its count is also 50% above the national county mean of 20.7. A larger declaration history records more federal actions; it is not a forecast of the county's next hazard.
How many major FEMA disaster declarations has Nassau County received?
Nassau County has received 21 major disaster declarations, representing 68% of all 31 disaster declarations.
How many flood insurance claims has Nassau County filed?
Nassau County has 51,518 National Flood Insurance Program (NFIP) claims totaling $2.3B in payments, with an average of $44.3K per claim.
Does FEMA's top risk-rated hazard match the highest Expected Annual Loss in Nassau County?
No. In Nassau County, Winter Weather has the highest National Risk Index rating (Very High), while Riverine Flooding leads Expected Annual Loss at about $183.9M. FEMA's risk score and dollar-loss model use different inputs, so the leaders often differ.
What was the worst year for disasters in Nassau County?
The most active year for disaster declarations in Nassau County was 2021, with 4 declarations. The county has FEMA disaster data spanning 1965 to 2024.
What is the FEMA National Risk Index score for Nassau County?
According to the FEMA National Risk Index, Nassau County, New York has an overall risk score of 97.1 out of 100 (Relatively High). Social vulnerability here rates Relatively Low, while community resilience comes in at Very High. The Expected Annual Loss (EAL) score is Relatively High, representing $298.6M in annualized losses.
Which natural hazard poses the greatest risk to Nassau County?
Based on FEMA NRI data, the highest-risk natural hazard in Nassau County as of the latest release is Winter Weather (risk rating: Very High). Other significant hazards include Ice Storm (Very High) and Coastal Flooding (Very High). FEMA's modeled event frequency puts winter weather here at an average of 9.8 times per year, drawn from 122 historical events on record. FEMA derives these ratings from historical event frequency, the assets exposed, and the community's vulnerability profile.
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 Nassau County · vintage 2026-08-25 · Methodology · New York profile · Verify with FEMA OpenFEMA · Verify with NOAA Storm Events