Grafton County Disaster Risk
Grafton County, New Hampshire
FEMA Risk Rating
Relatively Moderate
National Percentile
82th
of 3,144 counties
State Rank
#3
of 10 (1 = highest risk)
Flood Risk
90th
percentile
Hazard Risk Breakdown
Flood
River, coastal, and surface flooding risk
Moderate
Higher than 90% of US counties
Wildfire
Wildland and wildland-urban interface fire risk
Very Low
Higher than 31% of US counties
Tornado
Tornado and severe thunderstorm risk
Very Low
Higher than 24% of US counties
Earthquake
Seismic activity and ground shaking risk
Relatively Low
Higher than 70% of US counties
Hurricane
Tropical cyclone and hurricane risk
Relatively Low
Higher than 78% of US counties
Risk Overview
About Natural Disaster Risk in Grafton County, New Hampshire
Grafton County Exceeds National Risk
Grafton County's composite risk score of 81.77 significantly exceeds the national average of 69.89, placing it in the "Relatively Moderate" category. This mountain county faces notably higher natural disaster exposure than most American counties.
Highest-Risk County in New Hampshire
Grafton County ranks third-riskiest among New Hampshire's eight counties with a composite score of 81.77, substantially above the state average of 69.89. Only Hillsborough and Rockingham counties exceed Grafton's overall disaster risk.
Significantly Riskier Than Coos County
Grafton's 81.77 score towers over neighboring Coos County (72.77) and Belknap County (57.38) across the state. Its exceptional flood risk of 90.08 and elevated earthquake risk of 69.62 set it apart among northern counties.
Floods and Earthquakes Are Major Threats
Grafton County leads the state in flood risk at 90.08, driven by its mountainous terrain and major river systems including the Connecticut River. Earthquake risk of 69.62 reflects the county's proximity to tectonic activity, while wildfire and tornado risks remain moderate.
Essential: Flood and Earthquake Coverage
Grafton County residents must secure comprehensive flood insurance and earthquake coverage given flood risk of 90.08 and earthquake risk of 69.62—among the state's highest. Standard homeowners policies exclude both hazards, making separate policies critical.
Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor
Preparedness Guide
What to Prepare for in Grafton County
Top Hazards by Exposure
Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)
Risk Advisory: Grafton County
Risk Verdict
At the 82th percentile nationally, Grafton County sits in the upper half of U.S. counties for natural disaster exposure. At this risk level, having a documented household preparedness plan — not just awareness — is the meaningful next step for Grafton County residents.
Hazard Breakdown
Flood risk is Grafton County's dominant natural hazard, ranked at the 90th percentile nationally under FEMA's National Risk Index. Hurricane ranks second at the 78th percentile nationally. Additional tracked hazards include earthquake (70th percentile), wildfire (31th percentile), tornado (24th percentile).
Preparedness Context
At the 90th percentile nationally for flood risk, Grafton County residents benefit from understanding their specific flood zone status. Even one inch of floodwater causes significant structural damage to properties outside officially designated high-risk zones. Alongside flooding, hurricane exposure at the 78th percentile means households benefit from a multi-hazard preparedness plan rather than focusing on flood alone. A tested family preparedness plan specific to Grafton County's primary hazards — including how to shelter in place or evacuate, and who to call — provides more real protection than a general emergency kit sitting unused on a shelf.
Regional Context
The New Hampshire county average is 11.9 composite points below Grafton County's score, a gap that reflects the county's elevated position in the state's hazard distribution.
Is your household prepared for Grafton County's hazards?
Review FEMA's county-specific preparedness checklists and emergency planning guides.
Frequently Asked Questions
What is the natural disaster risk in Grafton County, NH?
What types of natural hazards affect Grafton County?
How does Grafton County risk compare to the New Hampshire average?
Is Grafton County at risk for flooding?
How is natural disaster risk measured?
Why is Grafton County higher risk than average?
Data Source
Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.
Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.