FloodZoneMap.org

Ontario County, New York Flood Zones

Check an Address in Ontario County

Enter any address in Ontario County, New York to see its FEMA flood zone

The Flooding Character of Ontario County

Flash flooding from thunderstorms is the primary flood concern in Ontario County. Over the last 30 years, the NOAA Storm Events Database has recorded 65 flash flood events and 17 general flood events. For example, on June 18, 2025, showers and thunderstorms trained over areas, causing flash flooding.

National Flood Insurance Program (NFIP) data shows that properties in Zone A have experienced the most claims, with 134 claims averaging $19,850 and an average water depth of 3.6 feet. Properties in Zone X_UNSHADED have also seen significant claims, with 27 claims averaging $14,609 and an average water depth of 1.4 feet. Homeowners in Zone A, Zone X_SHADED, and Zone X should pay particular attention to flood risk, as these areas have experienced substantial claims and water depths.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Ontario County

73 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read New York flood stories →

Flood Risk Data for Ontario County

Ontario County, New York has recorded 82 flood-related events since 1996 according to NOAA's Storm Events Database, including 65 flash floods and 17 river or area floods. The county has received 20 federal disaster declarations, 3 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Ontario County Disaster History

FEMA Disaster Declarations (1972–2024)

Disaster Declarations
20
Flood/Coastal Disasters
3
Latest Disaster
Remnants Of Tropical Storm Debby (2024-08-08)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Ontario County

DeclarationTypeDate
Remnants Of Tropical Storm DebbyTropical StormAug 8, 2024
Severe Storms And FloodingSevere StormJul 9, 2023
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storms And FloodingSevere StormMay 13, 2014
Hurricane SandyHurricaneOct 27, 2012
Severe Storms, Flooding, Tornadoes, And Straight-line WindsFloodApr 26, 2011
Hurricane Katrina EvacuationHurricaneAug 29, 2005
Severe Storms And FloodingSevere StormMay 13, 2004
Power OutageOtherAug 14, 2003

Recorded Flood Events in Ontario County

NOAA Storm Events Database (1996–2025)

Total Flood Events
82
River/Area Floods
17
Flash Floods
65
Total Property Damage
$13.4M
Flood Injuries
1

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Ontario County

TypeDateDamage
Flash FloodJun 18, 20250.00K
Flash FloodAug 9, 20240.00K
FloodJun 12, 20230.00K
Flash FloodJul 9, 20230.00K
Flash FloodJul 1, 20230.00K
FloodOct 30, 20210.00K
FloodOct 29, 20210.00K
FloodOct 27, 20210.00K
FloodOct 26, 20210.00K
FloodAug 19, 20210.00K

Ontario County Flood History

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 thunder...

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 se...

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 in...

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 wea...

Flash Flood — Jul 1, 2023

A weak wave aloft interacting with light winds and abundant moisture resulted in slow moving thunderstorms across the Finger Lakes late on the afternoon of the 1st. As storms merged together, they moved even slower with multiple rounds of heavy rain impacting portions of Ontario county. There were multiple reports of flooded roads in the Canandaigua and Geneva areas.

Source: NOAA National Weather Service Storm Events Database.

Ontario County NFIP Flood Insurance Claims

Total Claims Filed
212
Total Paid Out
$3.5M
Avg Claim
$23,971
Avg Water Depth
9.9 ft

Claims by Flood Zone

A Zones (High Risk)
134
X Shaded (500-yr)
11
X Unshaded (Low)
27

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Ontario County

FEMA assigns flood zone designations to areas in Ontario County, New York:

AE High Risk — 1% annual chance of flooding. Insurance required.

VE Very High Risk — Coastal flooding with wave action.

X (Shaded) Moderate Risk — 500-year floodplain.

X Low Risk — Outside major floodplains.

View all flood zone types →

Flood Insurance in Ontario County

Properties in Ontario County, New York that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.

Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.

Visit FloodSmart.gov to find an agent and get a quote.