Enter any address in Mercer County, New Jersey to see its FEMA flood zone
Flash flooding from thunderstorms is the most frequent type of flood event in Mercer County, NJ, with 74 occurrences in the last 30 years. Recent examples include flash flooding on August 6, 2024, caused by heavy rainfall ahead of the remnants of Tropical Storm Debby, which also brought damaging wind gusts. Coastal flooding has also occurred, such as on January 10, 2024, when southerly flow pushed water into coastal communities along the Delaware River, and on April 4, 2024, due to strong onshore flow from a storm moving up the coast.
National Flood Insurance Program (NFIP) data shows that properties in Zone A have experienced the most claims, with an average of 1,387 claims and an average water depth of 8.6 feet. However, properties in Zone X and Zone X_SHADED have seen higher average payouts, suggesting significant damage even with lower claim volumes and varying water depths. Homeowners in areas designated as Zone A, as well as those in coastal communities or near tidal rivers, should pay particular attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
26 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Mercer County, New Jersey has recorded 139 flood-related events since 1996 according to NOAA's Storm Events Database, including 74 flash floods and 51 river or area floods. The county has received 28 federal disaster declarations, 2 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1965–2021)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Remnants Of Hurricane Ida | Hurricane | Sep 1, 2021 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Winter Storm And Snowstorm | Severe Storm | Jan 22, 2016 |
| Hurricane Sandy | Hurricane | Oct 26, 2012 |
| Remnants Of Tropical Storm Lee | Severe Storm | Sep 28, 2011 |
| Hurricane Irene | Hurricane | Aug 27, 2011 |
| Severe Winter Storm And Snowstorm | Snowstorm | Dec 26, 2010 |
| Severe Storms And Flooding | Severe Storm | Mar 12, 2010 |
| Severe Storms And Inland And Coastal Flooding | Severe Storm | Apr 14, 2007 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Coastal Flood | Jan 10, 2024 | 0.00K |
| Flash Flood | Aug 6, 2024 | 40.00K |
| Flash Flood | Aug 6, 2024 | 0.00K |
| Coastal Flood | Apr 4, 2024 | 0.00K |
| Coastal Flood | Dec 18, 2023 | 0.00K |
| Flash Flood | Jul 15, 2023 | 0.00K |
| Coastal Flood | Dec 23, 2022 | 0.00K |
| Coastal Flood | Oct 29, 2021 | 0.00K |
| Flash Flood | Jul 29, 2021 | 0.00K |
| Flash Flood | Oct 26, 2021 | 0.00K |
Coastal Flood — Jan 10, 2024
A strong system affected the region with steady southerly flow pushing water up into coastal communities both along the ocean and within the Delaware River/Bay and Chesapeake Bay. Water levels on the tidal Delaware River were higher due to 2 to 4+ inches of rainfall.
Flash Flood — Aug 6, 2024
A predecessor rainfall event set up ahead of the remnants of Tropical Storm Debby. A hot and humid airmass was in place, resulting in a very moist and unstable airmass. A few showers and thunderstorms developed, producing damaging wind gusts across portions of New Jersey, downing trees and wires.
Coastal Flood — Apr 4, 2024
Strong onshore flow with a potent storm moving up the NJ/Delaware coast resulted in water piling up along the New Jersey coast and within the back bays. Water also moved up the Delaware Bay, which also resulted in tidal flooding within the Delaware River.
Coastal Flood — Dec 18, 2023
An area of low pressure passing over the region resulted in strong onshore flow and a push of water onshore and up the Delaware Bay and Delaware River, where moderate coastal flooding was observed.
Flash Flood — Jul 15, 2023
Thunderstorms brought locally heavy rain to parts of central New Jersey from the late afternoon into the evening of July 15. Rainfall totals were as high as 3 to 5 inches.
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Mercer County, New Jersey:
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.
Properties in Mercer County, New Jersey 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.