Hillsborough County Disaster Risk
Hillsborough County, New Hampshire
FEMA Risk Rating
Relatively Moderate
National Percentile
90th
of 3,144 counties
State Rank
#1
of 10 (1 = highest risk)
Flood Risk
93th
percentile
Hazard Risk Breakdown
Flood
River, coastal, and surface flooding risk
Moderate
Higher than 93% of US counties
Wildfire
Wildland and wildland-urban interface fire risk
Relatively Low
Higher than 67% of US counties
Tornado
Tornado and severe thunderstorm risk
Moderate
Higher than 83% of US counties
Earthquake
Seismic activity and ground shaking risk
Moderate
Higher than 88% of US counties
Hurricane
Tropical cyclone and hurricane risk
Moderate
Higher than 93% of US counties
Risk Overview
About Natural Disaster Risk in Hillsborough County, New Hampshire
Hillsborough County High-Risk Zone
Hillsborough County's composite risk score of 89.76 far exceeds the national average of 69.89, placing it in the "Relatively Moderate" category as the riskiest county in New Hampshire. Residents face significantly elevated natural disaster exposure compared to most U.S. counties.
Riskiest County in New Hampshire
Hillsborough County ranks most dangerous among New Hampshire's eight counties with a composite score of 89.76, a full 19.87 points above the state average of 69.89. Every major hazard category scores above state and national medians.
Dramatically Riskier Than Adjacent Counties
Hillsborough (89.76) substantially exceeds neighboring Merrimack County (78.21) and Rockingham County (85.85) across virtually all hazard categories. Its exceptional scores for tornado (82.60), flood (92.62), and earthquake (88.17) risks set it apart statewide.
Floods, Tornadoes, and Earthquakes Threaten
Hillsborough County faces extraordinary flood risk at 92.62, tornado risk at 82.60, and earthquake risk at 88.17—all among the nation's highest. These converging hazards make the county one of America's most disaster-exposed regions.
Comprehensive Insurance Is Non-Negotiable
Hillsborough County residents must obtain flood insurance (92.62 risk), earthquake coverage (88.17 risk), and tornado/wind protection (82.60 risk) as essential, not optional. Consult a local insurance agent to ensure policies address all major exposures without gaps.
Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor
Preparedness Guide
What to Prepare for in Hillsborough County
Top Hazards by Exposure
Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)
Risk Advisory: Hillsborough County
Risk Verdict
Natural hazard risk in Hillsborough County is higher than the majority of U.S. counties, with a national composite rank of 90th. Hillsborough County's elevated composite score reflects cumulative multi-hazard exposure; households should prepare for the county's two or three primary hazard types.
Hazard Breakdown
Flood risk is Hillsborough County's dominant natural hazard, ranked at the 93th percentile nationally under FEMA's National Risk Index. Hurricane ranks second at the 93th percentile nationally. Additional tracked hazards include earthquake (88th percentile), tornado (83th percentile), wildfire (67th percentile).
Preparedness Context
With flood ranked as the primary hazard at the 93th percentile nationally, Hillsborough County households should build a go-bag that includes important documents, medications, and supplies to sustain the family for at least three days if evacuation is needed. Secondary hurricane exposure at the 93th percentile adds a second preparedness layer; households should review coverage options and alert sign-up for both hazard types. A waterproof container for documents (insurance policies, ID, prescriptions) and a clear household communication plan for when phone networks are congested are the two highest-value low-cost preparedness steps for Hillsborough County households.
Regional Context
A composite score 19.9 points above the New Hampshire state average puts Hillsborough County in a higher-risk category than most counties in the state.
Is your household prepared for Hillsborough County's hazards?
Review FEMA's county-specific preparedness checklists and emergency planning guides.
Frequently Asked Questions
What is the natural disaster risk in Hillsborough County, NH?
What types of natural hazards affect Hillsborough County?
How does Hillsborough County risk compare to the New Hampshire average?
Is Hillsborough County at risk for flooding?
How is natural disaster risk measured?
Why is Hillsborough 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.