Tornado Risk in New Hampshire

All New Hampshire counties ranked by FEMA National Risk Index tornado score

Tornado risk — violently rotating columns of air capable of catastrophic local damage — is rated for 10 of 10 New Hampshire counties in FEMA's National Risk Index. Hillsborough County carries the state's highest tornado score at 82.6, with $7M in expected annual tornado losses.

No New Hampshire county reaches the High band for tornado, and expected annual losses from tornado total roughly $17M statewide. The full ranking below links to each county's complete 18-hazard risk profile.

County Rankings — Tornado

#CountyTornado ScoreRatingAnn. Freq.Ann. Loss
1 Hillsborough County
82.6
Medium 0.16 / yr $7M
2 Rockingham County
73.5
Medium 0.12 / yr $4M
3 Merrimack County
56.2
Low 0.13 / yr $2M
4 Cheshire County
43.6
Low 0.14 / yr $1M
5 Strafford County
42.2
Low 0.04 / yr $1M
6 Belknap County
31.4
Low 0.05 / yr $675K
7 Grafton County
24.4
Very Low 0.18 / yr $378K
8 Sullivan County
22.7
Very Low 0.07 / yr $383K
9 Carroll County
18.9
Very Low 0.11 / yr $227K
10 Coos County
10.6
Very Low 0.12 / yr $63K

10 New Hampshire counties with measurable tornado risk. See the national tornado ranking or all New Hampshire counties by overall risk.

Frequently Asked Questions

Which New Hampshire county has the highest tornado risk?

Hillsborough County has the highest FEMA tornado risk score in New Hampshire at 82.6 (Medium), with $7M in expected annual losses and about 0.16 events per year.

How many New Hampshire counties face significant tornado risk?

10 New Hampshire counties record measurable tornado risk in FEMA's National Risk Index; 0 of them are rated High or Very High.

Other Hazards in New Hampshire