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Onondaga County, New York Flood Zones

Check an Address in Onondaga County

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

The Flooding Character of Onondaga County

Flash flooding from intense thunderstorms is the dominant flood character in Onondaga County. Over the past 30 years, the NOAA Storm Events Database recorded 61 flash flood events, resulting in 2 fatalities. Recent examples include events in May 2025 and August 2023, where slow-moving storm systems and repeated thunderstorm complexes produced torrential rainfall, leading to localized flooding of roads, ditches, and urban areas.

National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A and Zone X have experienced the highest number of claims, with average payouts and water depths varying by zone. Homeowners in these zones, as well as those in Zone X_UNSHADED, should pay particular attention to their flood risk.

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

Read First-Hand Flood Stories from Onondaga County

43 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 Onondaga County

Onondaga County, New York has recorded 70 flood-related events since 1996 according to NOAA's Storm Events Database, including 61 flash floods and 9 river or area floods. The county has received 19 federal disaster declarations, 5 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Onondaga County Disaster History

FEMA Disaster Declarations (1972–2021)

Disaster Declarations
19
Flood/Coastal Disasters
5
Hurricane Disasters
1
Latest Disaster
Remnants Of Tropical Storm Fred (2021-08-18)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Onondaga County

DeclarationTypeDate
Remnants Of Tropical Storm FredHurricaneAug 18, 2021
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Hurricane SandyHurricaneOct 27, 2012
Severe Storms, Flooding, Tornadoes, And Straight-line WindsFloodApr 26, 2011
Hurricane Katrina EvacuationHurricaneAug 29, 2005
Severe Storms And FloodingSevere StormAug 13, 2004
Severe Storms And FloodingSevere StormMay 13, 2004
Power OutageOtherAug 14, 2003
Ice StormSevere Ice StormApr 3, 2003

Recorded Flood Events in Onondaga County

NOAA Storm Events Database (1996–2025)

Total Flood Events
70
River/Area Floods
9
Flash Floods
61
Total Property Damage
$36.4M
Flood Deaths
2

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Onondaga County

TypeDateDamage
Flash FloodMay 6, 20252.00K
Flash FloodDec 18, 20231.00K
Flash FloodAug 7, 20230.00K
Flash FloodAug 7, 20231.00K
Flash FloodAug 7, 20232.00K
Flash FloodAug 7, 20235.00K
Flash FloodAug 7, 202350.00K
Flash FloodAug 7, 202380.00K
Flash FloodJun 29, 20213.00K
Flash FloodOct 26, 2021150.00K

Onondaga County Flood History

Flash Flood — May 6, 2025

A slow moving upper level low pressure system interacted with a surface frontal boundary to induce torrential rain-producing thunderstorms. These storms moved into Central New York during the afternoon and repeatedly struck the same areas leading to localized flash flooding of roads, ditches and urban areas.

Flash Flood — Dec 18, 2023

Low pressure moved north along the Atlantic Seaboard spreading steady and heavy rain into central New York during the overnight hours. Rainfall amounts of 2 to 4 inches were observed along with a considerable amount of melting snow into area rivers and streams. Widespread flash flooding and river flooding occurred during this event.

Flash Flood — Aug 7, 2023

Thunderstorms developed ahead of a slow moving cold front tracking through Western and Central New York during the afternoon and evening. Numerous thunderstorm complexes moved over the same locations in Onondaga county producing up to 6 inches of rain in a short amount of time. Much of the area affected was predominantly urbanized land cover. Flooding of streets and drainage systems occurred fo...

Flash Flood — Jun 29, 2021

Slow moving thunderstorms embedded in a stagnant, hot and humid airmass produced torrential rainfall and urban flooding in the Syracuse, NY area.

Flash Flood — Oct 26, 2021

Deep moisture from the Atlantic Ocean was fed into a warm frontal zone located over Central New York by low pressure near New York City. This led to areas of moderate to heavy rainfall totaling between 3 to 5 inches of rain with locally higher amounts. This rainfall led to widespread flash flooding across the Southern Tier and Finger Lakes region.

Source: NOAA National Weather Service Storm Events Database.

Onondaga County NFIP Flood Insurance Claims

Total Claims Filed
779
Total Paid Out
$6.6M
Avg Claim
$11,733
Avg Water Depth
5.8 ft

Claims by Flood Zone

A Zones (High Risk)
450
X Shaded (500-yr)
24
X Unshaded (Low)
70

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

Flood Zone Types in Onondaga County

FEMA assigns flood zone designations to areas in Onondaga 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 Onondaga County

Properties in Onondaga 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.