Nantucket County, Massachusetts
Natural disaster risk, federal disaster history and flood insurance facts.
Nantucket County, Massachusetts has a very low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 61% of US counties. It ranks 13th of 14 counties in Massachusetts. The costliest hazards here are hurricanes, inland flooding and coastal flooding. FEMA estimates about $23 million a year in expected losses, or roughly $1,605 per resident. Since 1978 it has been included in 17 federal disaster or emergency declarations for natural events (9 major disasters). The most recent was in September 2023 (Hurricane Lee). About 1 in 13 homes here carry federal flood insurance (714 policies). Since 1978, federal flood insurance has paid about $18 million on 602 claims here, including $5.4 million for floods in 1991.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Nantucket County
- Know your evacuation zone and route before June 1.
- Ask about roof age, shutters and the separate wind or hurricane deductible on your home policy.
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Learn your evacuation zone; it is set by surge risk, not by distance from the beach.
- Ask about flood insurance even outside a mapped high-risk zone.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Hurricane | 90.9 | $17M | ||
| Inland flooding | 16.6 | $4M | ||
| Coastal flooding | 70.0 | $2M | ||
| Earthquake | 22.4 | $65K | ||
| Lightning | 6.1 | $36K | ||
| Tornado | 4.1 | $25K | ||
| Strong wind | 2.0 | $17K | ||
| Hail | 4.0 | $17K | ||
| Cold wave | 4.3 | $16K | ||
| Drought | 21.9 | $12K | ||
| Wildfire | 13.0 | $8K | ||
| Winter weather | 1.9 | $2K | ||
| Ice storm | 0.1 | $162 | ||
| Landslide | 2.3 | $4 |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is very low and community resilience is very high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Nantucket County. 2020s bar runs to November 2026.
By type
Most recent
Show all 17
Massachusetts also had 10 statewide declarations that did not name single counties.
Storm history since 1958
Tornado risk by county ›The National Weather Service has logged 24 storm reports in Nantucket County since 1958 and about $20,500 in reported damage. No tornadoes are on record here.
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Apr 28, 2017 | Lightning | Nantucket | $10K |
| Jun 7, 2006 | Flood | Countywide | $5K |
| Aug 13, 2023 | Thunderstorm Wind | Nantucket | $3K |
| Jul 23, 2011 | Thunderstorm Wind | Nantucket | $1K |
| Mar 25, 2016 | Lightning | Nantucket | $1K |
| Aug 13, 2023 | Lightning | Nantucket | $1K |
Source: NOAA Storm Events Database, county-based reports through Aug 13, 2023. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Hurricanes and tropical storms
Hurricane risk by county ›Since 1856, 16 hurricanes and 20 tropical storms have passed within 65 miles of the center of Nantucket County, 15 of them since 1950. The strongest was Hurricane Gerda (1969), with top winds near 120 mph about 46 miles away.
Strongest storms nearby
| Date | Storm | Strength | Closest |
|---|---|---|---|
| Sep 9, 1969 | Gerda | Category 3, 120 mph | 46 mi |
| Sep 11, 1954 | Edna | Category 2, 110 mph | 34 mi |
| Oct 4, 1869 | Unnamed | Category 2, 105 mph | 49 mi |
| Aug 19, 1991 | Bob | Category 1, 95 mph | 62 mi |
| Aug 26, 1924 | Unnamed | Category 1, 95 mph | 64 mi |
| Sep 23, 1885 | Unnamed | Category 1, 90 mph | 46 mi |
Most recent storms
| Date | Storm | Strength | Closest |
|---|---|---|---|
| Jul 5, 2014 | Arthur | Category 1, 75 mph | 65 mi |
| Jul 21, 2006 | Beryl | Tropical storm, 50 mph | 65 mi |
| Aug 31, 2004 | Hermine | Tropical storm, 40 mph | 53 mi |
| Jul 25, 1997 | Danny | Tropical storm, 60 mph | 57 mi |
| Aug 19, 1991 | Bob | Category 1, 95 mph | 62 mi |
| Aug 7, 1988 | Alberto | Tropical storm, 40 mph | 59 mi |
Source: NOAA National Hurricane Center best-track records (HURDAT2), 1851 to 2025 for the Atlantic and 1949 to 2025 for the eastern Pacific. A storm counts if its track passed within 65 miles of the county's center while it was a tropical storm or hurricane. Strength is the storm's top sustained wind at that point, not the wind measured in the county. Older storms over the open sea were sometimes missed.
Flood insurance in Nantucket County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in Nantucket County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 12,594 housing units.
Compare in Massachusetts
All 14 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Middlesex County | Inland flooding | |
| Worcester County | Inland flooding | |
| Essex County | Inland flooding | |
| Suffolk County | Inland flooding | |
| Norfolk County | Inland flooding | |
| Bristol County | Inland flooding | |
| Plymouth County | Inland flooding | |
| Hampden County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Dukes County | 19 |
Common questions about Nantucket County
What is the biggest natural hazard in Nantucket County?
Hurricane has the highest expected yearly losses in Nantucket County, about $16.9 million a year in FEMA's estimate. Inland flooding is second at $3.8 million.
How many federal disasters has Nantucket County had?
Nantucket County has been included in 17 federal disaster or emergency declarations for natural events since 1978, including 9 major disasters. The most recent was Hurricane Lee in September 2023.
Is Nantucket County a high-risk place to live?
Its overall rating is Very Low, 13th highest of 14 in Massachusetts. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in Nantucket County?
Standard home insurance does not cover flooding. About 1 in 13 homes in Nantucket County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has Nantucket County had?
NOAA records list 0 tornadoes in Nantucket County since 1950. The weather service has also logged 2 hail reports and 6 floods here.
How many hurricanes have hit Nantucket County?
NOAA's hurricane records show 16 hurricanes and 20 tropical storms passing within 65 miles of the center of Nantucket County, including 1 major hurricane (Category 3 or stronger). The strongest was Hurricane Gerda (1969), with winds near 120 mph.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.