FloodZoneMap.org

Coos County, New Hampshire Flood Zones

Check an Address in Coos County

Enter any address in Coos County, New Hampshire to see its FEMA flood zone

The Flooding Character of Coos County

Flash flooding from heavy rainfall events is a significant concern in Coos County. Over the past 30 years, NOAA Storm Events data shows 74 flood events and 60 flash flood events, alongside 4 tropical storm events. For example, on July 10, 2024, remnants of Tropical Storm Beryl combined with a low-pressure system to bring 3 to 5 inches of rain to the region, causing flash flooding after preceding heavy rainfall saturated the ground.

National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A have experienced 43 claims with an average payout of $8,047 and an average water depth of 2.9 feet. Properties in Zone X, though fewer in number with 9 claims, have seen significantly higher average payouts of $13,388 with an average water depth of 20.2 feet. Homeowners in Zone A, Zone X, and areas with properties that may not be built to Base Flood Elevation (BFE) should pay particular attention to flood risk.

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

Read First-Hand Flood Stories from Coos County

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

Read New Hampshire flood stories →

Flood Risk Data for Coos County

Coos County, New Hampshire has recorded 138 flood-related events since 1996 according to NOAA's Storm Events Database, including 60 flash floods and 74 river or area floods. The county has received 28 federal disaster declarations, 6 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Coos County Disaster History

FEMA Disaster Declarations (1973–2024)

Disaster Declarations
28
Flood/Coastal Disasters
6
Hurricane Disasters
2
Latest Disaster
Severe Storm And Flooding (2024-07-10)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Coos County

DeclarationTypeDate
Severe Storm And FloodingSevere StormJul 10, 2024
Severe Storm And FloodingSevere StormDec 17, 2023
Severe Storms And FloodingFloodJul 9, 2023
Severe Storm And FloodingSevere StormDec 22, 2022
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe Storm And FloodingSevere StormOct 29, 2017
Severe Storms And FloodingSevere StormJul 1, 2017
Hurricane SandyHurricaneOct 26, 2012
Severe StormSevere StormOct 29, 2011

Recorded Flood Events in Coos County

NOAA Storm Events Database (1996–2025)

Total Flood Events
138
River/Area Floods
74
Flash Floods
60
Hurricanes/Tropical Storms
4
Total Property Damage
$13.9M
Flood Injuries
1

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Coos County

TypeDateDamage
Flash FloodJul 11, 20240.00K
Flash FloodJul 10, 20240.00K
Flash FloodJul 6, 20240.00K
Flash FloodJul 18, 20230.00K
FloodDec 18, 2023300.00K
FloodDec 18, 20230.00K
Flash FloodDec 18, 20230.00K
Flash FloodDec 18, 2023500.00K
Flash FloodJul 11, 20230.00K
FloodJul 10, 20230.00K

Coos County Flood History

Flash Flood — Jul 11, 2024

On July 10th the remnants of Tropical Storm Beryl phased with a low pressure system out of the Great Lakes to bring multiple rounds of heavy rainfall to northern New England, including Maine and New Hampshire. The previous 3 days had brought a swath of heavy rain just north of the White Mountains, saturating the ground and making it ideal for runoff. During the roughly 36 hour period, 3 to as m...

Flash Flood — Jul 10, 2024

On July 10th the remnants of Tropical Storm Beryl phased with a low pressure system out of the Great Lakes to bring multiple rounds of heavy rainfall to northern New England, including Maine and New Hampshire. The previous 3 days had brought a swath of heavy rain just north of the White Mountains, saturating the ground and making it ideal for runoff. During the roughly 36 hour period, 3 to as m...

Flash Flood — Jul 6, 2024

A slow moving cold front triggered scattered thunderstorms across northern New Hampshire on July 6th. Repeating storms across Grafton and Coos Counties produced locally heavy rainfall resulting in localized areas of road washouts.

Flash Flood — Jul 18, 2023

Scattered showers and thunderstorms with heavy rainfall developed across the White Mountains and areas northward on the afternoon of the 18th. Moist air supported torrential rainfall rates between 2 to 3 inches an hour, all of which fell over saturated soils. Localized flash flooding resulted where storms trained over the same locations.

Flood — Dec 18, 2023

Low pressure began organizing in the Gulf of Mexico on the 16th, setting record low sea level pressures as it traversed the Southeast through the 17th. Strong high pressure over the North Atlantic created a deep southeasterly flow that drew warm air into New England ahead of the approaching storm. By the time precipitation arrived on the evening of the 17th, temperatures were warm enough for ra...

Source: NOAA National Weather Service Storm Events Database.

Coos County NFIP Flood Insurance Claims

Total Claims Filed
82
Total Paid Out
$588,231
Avg Claim
$9,337
Avg Water Depth
11.0 ft

Claims by Flood Zone

A Zones (High Risk)
43
X Shaded (500-yr)
11
X Unshaded (Low)
3

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

Flood Zone Types in Coos County

FEMA assigns flood zone designations to areas in Coos County, New Hampshire:

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 Coos County

Properties in Coos County, New Hampshire 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.