263 flood insurance claims·$3.8M paid·3 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 Ontario County, New York. 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.
Flash flooding from summer thunderstorms dominates the flood character of Ontario County, NY, accounting for 65 out of 82 total flood events recorded in the NOAA Storm Events Database over the last 30 years, alongside 17 general flood events.
This hazard is driven by weather patterns such as those on June 18, 2025, when showers and thunderstorms developed along a Lake Erie lake breeze boundary. High-moisture airmasses and slow-moving cold fronts from Lake Ontario caused heavy rainfall, with storms training over the same areas long enough to produce flash flooding issues.
National Flood Insurance Program claims data indicates that residents in Zone A should pay the most attention, as this zone accounts for 161 claims with an average payout of $24,892 and an average recorded water depth of 10 inches. Property owners in Zone X_UNSHADED (38 claims, average payout of $23,366, average water depth of 4 inches), Zone X (31 claims, average payout of $18,932, average water depth of 11 inches), and Zone X_SHADED (14 claims, average payout of $16,128, average water depth of 13 inches) have also experienced property damage and should review their risk.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
24% of Ontario County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
213 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 1993, with 52 claims and $480,646 paid.
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.
73 NOAA storm reports from Ontario County describe what happened, in the words of the forecasters who covered it. Read the New York flood stories →
20 federal disaster declarations since 1972, 3 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Remnants Of Tropical Storm Debby | Aug 8, 2024 |
| Severe Storms And Flooding | Jul 9, 2023 |
| Severe Storms And Flooding | May 13, 2014 |
| Hurricane Sandy | Oct 27, 2012 |
| Severe Storms, Flooding, Tornadoes, And Straight-line Winds | Apr 26, 2011 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Storms And Flooding | May 13, 2004 |
| Power Outage | Aug 14, 2003 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
82 since 1996: 65 flash floods and 17 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Jun 18, 2025 | — |
| Flash Flood | Aug 9, 2024 | — |
| Flood | Jun 12, 2023 | — |
| Flash Flood | Jul 9, 2023 | — |
| Flash Flood | Jul 1, 2023 | — |
| Flood | Oct 30, 2021 | — |
| Flood | Oct 29, 2021 | — |
| Flood | Oct 27, 2021 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · Jun 18, 2025. Showers and thunderstorms developed along a Lake Erie lake breeze boundary during the late morning of June 18th. With the very high moisture laden airmass over the area, heavy rain occurred within some of the showers and thunderstorms that developed. Some of the thunderstorms, especially early, trained over the same area long enough to cause flash flooding issues. Additional showers and thunderstorms developed dur…
Flash Flood · Aug 9, 2024. The remnants of Tropical Cyclone Debby tracked northeast across Central New York on Friday August 9. As the system tracked across the region, heavy rain pushed into parts of the forecast area, with the heaviest rain falling over the Southern Tier, Finger Lakes and up to the North Central New York areas. Flash Flooding was the primary threat from the remnants of the system, but some strong to severe thunderstorms a…
Flood · Jun 12, 2023. A cold front with a feed of rich moisture resulted in widespread moderate to heavy rain and a few instances of mainly road flooding from late in the afternoon on the 12th through early evening hours of the 12th. The heaviest rain and flooding reports received were centered across the Finger Lakes. No lightning was observed with the heavy rain. Some of the heaviest rain reports included; 2.95 inches at Clifton Spri…
Flash Flood · Jul 9, 2023. There was significant flash flooding including a building collapse and a water rescue in Canandaigua in the late afternoon as some estimates point to a 100 year flood event. A state of emergency was declared for Ontario county. Flash flooding also occurred in portions of Lewis County into the early evening. Numerous roads in these counties were flooded and impassable with some washed out. A weak wave of low pressu…
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 Ontario 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.