845 flood insurance claims·$12.7M paid·13 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Nassau County, Florida. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
Nassau County experiences a flood risk profile driven primarily by tropical storms and frequent coastal flood events. Over the last 30 years, NOAA records show 22 tropical storm events resulting in 1 death, alongside 19 coastal flood events, 16 general flood events, 8 flash floods, 1 storm surge event, and 1 hurricane.
Recent weather patterns illustrate these localized hazards. In September 2024, Tropical Storm Helene produced peak wind gusts of 55 to 75 mph across the eastern half of the region as it tracked quickly north-northeast following a Category 4 landfall in the Florida Big Bend. Later, an extended local nor'easter from October 9 through 12, 2025, brought gusty winds of 40 to 51 mph and produced moderate tidal flooding along the coast, the Intracoastal Waterway, and inland areas.
Property owners should review their flood risk based on historical claims data across FEMA zones. Zone A recorded 393 claims with an average water depth of 7 inches and an average payout of $23,602, while Zone X logged 294 claims with an average water depth of 14 inches and an average payout of $26,729. Zone X Unshaded recorded 83 claims averaging 2 inches of water, Zone V recorded 46 claims averaging 10 inches of water, and Zone X Shaded recorded 27 claims averaging 1 inch of water. Coastal properties and homes situated within high-risk flood zones should pay the closest attention to these hazards.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
20% of Nassau County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
549 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 9 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 2017, with 178 claims and $5.2M paid, the year of Hurricane Irma.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
33 NOAA storm reports from Nassau County describe what happened, in the words of the forecasters who covered it. Read the Florida flood stories →
40 federal disaster declarations since 1973, 13 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Hurricane Milton | Oct 5, 2024 |
| Hurricane Helene | Sep 23, 2024 |
| Hurricane Debby | Aug 1, 2024 |
| Tropical Storm Debby | Aug 1, 2024 |
| Hurricane Idalia | Aug 27, 2023 |
| Tropical Storm Idalia | Aug 27, 2023 |
| Hurricane Nicole | Nov 7, 2022 |
| Tropical Storm Nicole | Nov 7, 2022 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
67 since 1996: 8 flash floods, 16 river or area floods and 20 coastal floods or surges.
| Event | Date | Damage |
|---|---|---|
| Coastal Flood | Sep 9, 2025 | — |
| Coastal Flood | Oct 9, 2025 | — |
| Flood | Sep 7, 2025 | — |
| Tropical Storm | Sep 26, 2024 | — |
| Tropical Storm | Oct 10, 2024 | — |
| Tropical Storm | Aug 4, 2024 | — |
| Tropical Storm | Aug 30, 2023 | — |
| Flood | Jul 28, 2023 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Coastal Flood · Sep 9, 2025. Persistent onshore (northeasterly) winds along the local coast for several days created a local nor'easter which produced gusty coastal winds around 40 mph at times, waves of showers and isolated storms, rough surf, frequent rip currents and coastal / tidal flooding impacts around high tides at the northeast Florida coast, Intracoastal Waterway and the St. Johns River basin.
Coastal Flood · Oct 9, 2025. An extended duration local nor'easter wind event developed October 9th and persisted through the 12th between high pressure wedging down the SE US coast and a sharpening coastal trough axis over the local coastal waters. Gusty winds of 40-51 mph impacted coastal areas, with the strongest winds from 10/9 in the afternoon through 10/10 in the evening along the Duval county coast of 51 mph. Tidal flooding reached mod…
Flood · Sep 7, 2025. A front approached from the northwest with a moist and unstable airmass ahead of it across the local area. Slow steering flow and high moisture across the area ahead of the front produced sea breeze showers and storms that produced locally heavy rainfall. Weak shear but high instability across the local marine waters produced waterspouts.
Tropical Storm · Sep 26, 2024. Hurricane Helene made landfall as a category 4 with peak winds of near 140 mph in the Florida Big |Bend just east of the Aucilla River Entrance in Taylor County, late Thursday evening September 26, |2024. Helene's main impact to southeast Georgia and northeast Florida was wind damage as it |tracked quickly north-northeast. The very powerful hurricane and the forward motion produced a |wide swath of wind damage ac…
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Nassau County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.