St. John Island, U.S. Virgin Islands: Natural Disaster Risk and History
FEMA's National Risk Index (v1.20, December 2025) gives St. John Island, U.S. Virgin Islands no overall risk score (insufficient data); the hazards with the largest estimated yearly losses are hurricanes, earthquakes and inland (river and flash) flooding, $6.7 million a year in all.
OpenFEMA lists 25 federal disaster declarations that included St. John Island since 1970, not counting 2 for COVID-19; the latest is DR-4841-VI (Tropical Storm Ernesto, declared 25 October 2024). NOAA's Storm Prediction Center has no tornado on record touching St. John Island from 1950 to 2025.
Official warnings now All official warnings
Population 3,882 Buildings worth $1.4 billion Area 93 sq mi FIPS 78020
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Hurricane | Insufficient Data | — | $5.4 million | about once every 3.8 years | 61 |
| Earthquake | Insufficient Data | — | $825,116 | about once every 7.9 years | — |
| Inland flooding | Insufficient Data | — | $385,830 | about once every 3.1 years | 9 |
| Tsunami | Insufficient Data | — | $70,188 | about once every 24 years | 9 |
| Coastal flooding | Insufficient Data | — | $12,506 | about once every 4.8 years | — |
| Tornado | Insufficient Data | — | $534 | rarer than once in 1,000 years | 0 |
| Volcanic activity | Insufficient Data | — | $93 | about once every 99 years | 1 |
| Hail | Insufficient Data | — | $44 | about once every 602 years | 0.1 |
| Strong wind | Insufficient Data | — | $13 | about once every 602 years | 1 |
| Cold wave | Insufficient Data | — | — | — | 0 |
| Drought | Insufficient Data | — | — | — | 0 |
| Heat wave | Insufficient Data | — | — | — | 0 |
| Winter weather | Insufficient Data | — | — | — | 0 |
| Avalanche | Not Applicable | — | — | — | — |
| Ice storm | Not Applicable | — | — | — | — |
| Landslide | Insufficient Data | — | — | — | — |
| Lightning | Insufficient Data | — | — | — | — |
| Wildfire | Insufficient Data | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 25
Most common: Hurricane 17, Flood 3, Tropical Storm 2, Severe Storm 2.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 4 | Flood ×2, Hurricane, Drought |
| 1980s | 3 | Hurricane ×2, Flood |
| 1990s | 5 | Hurricane ×5 |
| 2000s | 3 | Hurricane ×2, Severe Storm |
| 2010s | 7 | Hurricane ×6, Severe Storm |
| 2020s | 3 | Tropical Storm ×2, Hurricane |
The last 10
Widest declarations that included St. John Island
- Tropical Storm Ernesto (2024, DR-4841-VI): 3 U.S. Virgin Islands counties designated.
- Tropical Storm Ernesto (2024, EM-3611-VI): 3 U.S. Virgin Islands counties designated.
- Potential Tropical Cyclone Nine (2020, EM-3531-VI): 3 U.S. Virgin Islands counties designated.
Named storms in its declarations: Tropical Storm Ernesto (2024), Hurricane Dorian (2019), Hurricane Maria (2017), Hurricane Irma (2017), Hurricane Earl (2010), Hurricane Omar (2008), Tropical Storm Jeanne (2004), Hurricane Lenny (1999), Hurricane Georges (1998), Hurricane Bertha (1996), Hurricane Marilyn (1995), Hurricane Hugo (1989), Tropical Storm Klaus (1984), Hurricane David (1979).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. U.S. Virgin Islands also had 2 statewide declarations with no county list.
Tornado record since 1950 0
No tornado in NOAA's Storm Prediction Center record touched St. John Island between 1950 and 2025. That does not mean one cannot happen.
How St. John Island compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| St. John Island (this page) | — | Insufficient Data | — | — |
| St. Thomas Island | 20 km | Insufficient Data | — | — |
| Culebra Municipio, PR | 58 km | Insufficient Data | — | — |
| St. Croix Island | 67 km | Insufficient Data | — | — |
| Vieques Municipio, PR | 78 km | Insufficient Data | — | — |
| Fajardo Municipio, PR | 98 km | Insufficient Data | — | — |
Nearest by distance between county centres. Every county in U.S. Virgin Islands, ranked.
Vulnerability and resilience
| Social vulnerability | Data Unavailable |
|---|---|
| Community resilience | Data Unavailable |
| Community risk factor | — |
| Expected annual loss, all hazards | $6.7 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for St. John Island's main hazards
- Right now: official warnings · all official warnings on Global Incident Tracker.
- Hurricane: Is there a hurricane now? · Cyclone preparation
- Earthquake: Earthquakes today · Earthquake safety guide
- Inland flooding: Flood safety: why shallow water kills · Floods recorded
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about St. John Island
What natural disasters is St. John Island, U.S. Virgin Islands most at risk from?
FEMA's National Risk Index (v1.20, December 2025) gives St. John Island, U.S. Virgin Islands no overall risk score (insufficient data); the hazards with the largest estimated yearly losses are hurricanes, earthquakes and inland (river and flash) flooding, $6.7 million a year in all.
How many federal disaster declarations has St. John Island had?
OpenFEMA lists 25 federal disaster declarations that included St. John Island since 1970, not counting 2 for COVID-19; the latest is DR-4841-VI (Tropical Storm Ernesto, declared 25 October 2024). Another 2 U.S. Virgin Islands declarations were made statewide without a county list.
How many tornadoes have hit St. John Island?
NOAA's Storm Prediction Center has no tornado on record touching St. John Island from 1950 to 2025.
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.