Hillsborough County, New Hampshire severe weather history spans 507 recorded events between 1955 and 2026. The dominant hazard is thunderstorm wind, accounting for 53.1% of all recorded events. It ranks #849 nationally and #4 in New Hampshire.
507
Recorded events
1
Direct deaths
20
Direct injuries
$11.1M
Property damage
The record
What the Hillsborough County, New Hampshire severe weather history record shows
Across the archive, Hillsborough County, New Hampshire severe weather history averages 7.1 recorded events a year. The busiest stretch on record is the 2020s, with 175 events logged in that decade alone. Roughly 52 events fall before 1990 and 455 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Hillsborough County, New Hampshire record is thunderstorm wind, responsible for 1 direct deaths. The costliest is flood, with $3.7M in reported property damage. In total, 7 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Hillsborough County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 269 | 1 | $1.7M | 96 | 1956–2026 |
| Hail | 110 | 0 | $13K | 2 | 1955–2025 |
| Flash Flood | 51 | 0 | $2.9M | 0 | 1996–2025 |
| Flood | 31 | 0 | $3.7M | 0 | 1997–2025 |
| Lightning | 24 | 0 | $1.3M | 0 | 1996–2014 |
| Tornado | 19 | 0 | $1.4M | F3 | 1956–1998 |
| Heavy Rain | 3 | 0 | $0 | 0 | 1996–2000 |
Decade by decade
Hillsborough County, New Hampshire severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
21 mapped tornado paths intersect this county: 18 touched down inside it and 3 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1963-05-20 | EF3 | 0 | 0 | 14.0 mi | Crossed in |
| 1998-05-31 | EF2 | 0 | 0 | 0.5 mi | Touched down here |
| 1997-07-03 | EF2 | 0 | 0 | 2.0 mi | Touched down here |
| 1968-07-17 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1965-08-28 | EF2 | 0 | 0 | 2.0 mi | Touched down here |
| 1963-06-09 | EF2 | 0 | 0 | 10.0 mi | Touched down here |
| 1961-07-02 | EF2 | 0 | 0 | 2.0 mi | Touched down here |
| 1986-06-16 | EF1 | 0 | 0 | 12.0 mi | Crossed in |
| 1984-07-05 | EF1 | 0 | 0 | 0.1 mi | Touched down here |
| 1984-07-05 | EF1 | 0 | 0 | 7.0 mi | Crossed in |
Significant events
Deadliest events on record in Hillsborough County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jul 6, 1999 | Thunderstorm Wind | AMHERST | 1 | 0 | $0 |
| Aug 13, 2003 | Lightning | PELHAM | 0 | 9 | $0 |
| Aug 23, 2020 | Thunderstorm Wind | DAVIS | 0 | 6 | $0 |
| Aug 18, 1999 | Lightning | MANCHESTER | 0 | 2 | $0 |
| Jul 1, 2015 | Thunderstorm Wind | NASHUA | 0 | 1 | $0 |
| Jul 9, 1996 | Lightning | MONT VERNON | 0 | 1 | $0 |
| Aug 20, 1968 | Tornado | 0 | 1 | $25K |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Flooding closed part of Route 202 in Peterborough, Route 122 and South Merrimack Road in Hollis, and widespread urban flooding in Nashua and Manchester. A mudslide closed a portion of Route 101 in Wilton. Minor to moderate flooding was observed on the larger mainstem rivers. The Merrimack River at Nashua crested at 23.5 feet at 8 am on the 17th (flood stage is 18 feet), while at Goffs Falls the Merrimack crested at 16.8 feet at 1 pm on the 17th (flood stage is 11 feet). The Contoocook River at Peterborough crested at 7.2 feet at 1 pm on the 16th (flood stage is 5.5 feet. The Souhegan River at Merrimack crested at 12.7 feet at 545 am on the 17th (flood stage is 9 feet).
Approximately $1 Million in road damages reported town wide in Peterborogh. Old Town Farm Rd and Old Jaffrey Rd received significant damage. Old Town Farm Road is a dead end and had 18 homes isolated by the road washouts.
The NWS Storm survey team confirmed straight line wind damage in Milford, NH due to a microburst. The team observed 7 damaged homes….two destroyed vehicles and approximately 150 downed trees. No known injuries or fatalities occurred with this |storm.
Context
Risk, population and federal disasters
Relatively Moderate
FEMA NRI risk rating
426,378
Population (ACS)
$421K
Median home value
31
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Apr 3, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Mar 25, 2015 | Severe Storm | SEVERE WINTER STORM AND SNOWSTORM | DR |
| Mar 19, 2013 | Severe Storm | SEVERE WINTER STORM AND SNOWSTORM | DR |
| Oct 30, 2012 | Hurricane | HURRICANE SANDY | EM |
| Dec 5, 2011 | Severe Storm | SEVERE STORM AND SNOWSTORM | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Hillsborough County, New Hampshire?
507 events are on record between 1955 and 2026, causing 1 direct deaths and $11.1M in property damage.
What is the most common severe weather hazard in Hillsborough County?
Thunderstorm Wind, with 269 recorded events — 53.1% of everything in the archive for this county.
How many tornadoes have crossed Hillsborough County?
21 mapped tornado paths intersect the county boundary; 18 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Hillsborough County?
31 federal disaster declarations from FEMA include Hillsborough County, each tied to a specific incident period.
How risky is Hillsborough County compared with the rest of the country?
FEMA's National Risk Index rates Hillsborough County as relatively moderate risk, placing it in the 90 percentile of its state for expected annual loss.
Where does the Hillsborough County, New Hampshire severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Grafton County 775
- Merrimack County 460
- Coos County 364
- Rockingham County 537
- Cheshire County 567
- Strafford County 256
Cite this page
“Hillsborough County, New Hampshire.” Severe Weather History. severeweatherhistory.com/county/new-hampshire/hillsborough-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.