NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit Merrimack, NH
Every tropical system within 75 miles since 1851 and every tornado within 25 miles since 1950.
Data: NOAA NHC HURDAT2 and NOAA SPC tornado and hail reports, through 2025 · Updated
42 tropical systems have passed within 75 miles of Merrimack, New Hampshire since 1851, 6 of them at hurricane strength; the most recent was Elsa in 2021. Since 1950, 36 tornadoes have touched down within 25 miles, 2 of them rated EF3 or stronger.
- Hurricanes
- 6
- Tropical storms
- 36
- Tornadoes
- 36
- EF3 or stronger
- 2
within 75 mi, since 1851
below hurricane strength
within 25 mi, since 1950
2 deaths in all
What the records show for Merrimack
The strongest storm to pass near Merrimack was an unnamed storm in 1869, a Category 2 hurricane with 104 mph winds when its centre passed 65 miles away. The closest pass by a hurricane was Carol in 1954, whose centre came within 2 miles. The record near Merrimack begins with an unnamed storm in 1851; the most recent system was Elsa in 2021, a tropical storm 60 miles away. The busiest decade was the 1890s, with 6 systems. Of the 42 systems, 5 have come since 2000. Merrimack has more hurricanes within 75 miles than 72% of the 142 New Hampshire cities on this site. The highest rating among the 36 tornadoes within 25 miles is F3, reached 2 times; the most recent, on September 29, 1974, came within 23 miles. The deadliest, an EF2 on July 24, 2008, killed 1 person. Of the 36, one had a path within 5 miles of the city centre, and one has come since 2000. July has had the most tornadoes, 19. The most recent tornado was on July 24, 2008. Merrimack has more tornadoes within 25 miles than 78% of the 142 New Hampshire cities. Hail has been reported within 10 miles 76 times since 1963, with stones up to 2 inches (hen egg size). Merrimack has more hail reports within 10 miles than 86% of the 142 New Hampshire cities.
Compare Merrimack's storm record with another city →
Tropical storms and hurricanes near Merrimack
| Year | Storm | Closest | Strength when closest | Peak |
|---|---|---|---|---|
| 2021 | ElsaJul 9 | 60 mi | Tropical storm (51 mph) | Category 1 |
| 2013 | AndreaJun 8 | 63 mi | Tropical storm (46 mph) | Tropical storm |
| 2011 | IreneAug 28 | 64 mi | Tropical storm (55 mph) | Category 3 |
| 2008 | HannaSep 7 | 49 mi | Tropical storm (52 mph) | Category 1 |
| 2007 | BarryJun 5 | 46 mi | Tropical storm (40 mph) | Tropical storm |
| 1999 | FloydSep 17 | 13 mi | Tropical storm (54 mph) | Category 4 |
| 1996 | BerthaJul 14 | 25 mi | Tropical storm (68 mph) | Category 3 |
| 1991 | BobAug 19 | 53 mi | Category 1 (85 mph) | Category 3 |
| 1985 | GloriaSep 27 | 24 mi | Category 1 (77 mph) | Category 4 |
| 1976 | BelleAug 10 | 48 mi | Tropical storm (40 mph) | Category 3 |
| 1971 | DoriaAug 28 | 44 mi | Tropical storm (53 mph) | Tropical storm |
| 1968 | Unnamed 1968 stormSep 11 | 55 mi | Tropical storm (56 mph) | Tropical storm |
| 1961 | EstherSep 26 | 74 mi | Tropical storm (49 mph) | Category 5 |
| 1961 | Unnamed 1961 stormSep 15 | 11 mi | Tropical storm (67 mph) | Tropical storm |
| 1960 | DonnaSep 12 | 16 mi | Tropical storm (70 mph) | Category 4 |
| 1960 | BrendaJul 30 | 5 mi | Tropical storm (46 mph) | Tropical storm |
| 1954 | CarolAug 31 | 2 mi | Category 2 (96 mph) | Category 3 |
| 1944 | Unnamed 1944 stormSep 15 | 58 mi | Category 1 (74 mph) | Category 5 |
| 1934 | Unnamed 1934 stormSep 9 | 13 mi | Tropical storm (46 mph) | Category 2 |
| 1923 | Unnamed 1923 stormOct 19 | 18 mi | Tropical storm (49 mph) | Tropical storm |
| 1916 | Unnamed 1916 stormJul 21 | 49 mi | Tropical storm (56 mph) | Category 2 |
| 1916 | Unnamed 1916 stormMay 17 | 18 mi | Tropical storm (58 mph) | Tropical storm |
| 1915 | Unnamed 1915 stormAug 5 | 61 mi | Tropical storm (40 mph) | Category 1 |
| 1908 | Unnamed 1908 stormMay 31 | 25 mi | Tropical storm (40 mph) | Category 1 |
| 1902 | Unnamed 1902 stormJun 17 | 41 mi | Tropical storm (40 mph) | Tropical storm |
| 1899 | Unnamed 1899 stormNov 1 | 53 mi | Tropical storm (52 mph) | Category 2 |
| 1897 | Unnamed 1897 stormSep 24 | 24 mi | Tropical storm (44 mph) | Tropical storm |
| 1896 | Unnamed 1896 stormSep 10 | 49 mi | Tropical storm (59 mph) | Category 3 |
| 1894 | Unnamed 1894 stormOct 10 | 6 mi | Tropical storm (60 mph) | Category 3 |
| 1893 | Unnamed 1893 stormAug 29 | 39 mi | Tropical storm (60 mph) | Category 3 |
| 1893 | Unnamed 1893 stormAug 24 | 69 mi | Tropical storm (68 mph) | Category 3 |
| 1888 | Unnamed 1888 stormSep 12 | 50 mi | Tropical storm (40 mph) | Tropical storm |
| 1888 | Unnamed 1888 stormAug 22 | 53 mi | Tropical storm (48 mph) | Category 3 |
| 1878 | Unnamed 1878 stormOct 24 | 2 mi | Tropical storm (59 mph) | Category 2 |
| 1874 | Unnamed 1874 stormSep 30 | 3 mi | Tropical storm (69 mph) | Category 1 |
| 1872 | Unnamed 1872 stormOct 27 | 72 mi | Tropical storm (46 mph) | Category 1 |
| 1869 | Unnamed 1869 stormOct 4 | 65 mi | Category 2 (104 mph) | Category 2 |
| 1869 | Unnamed 1869 stormSep 8 | 21 mi | Category 1 (92 mph) | Category 3 |
| 1861 | Unnamed 1861 stormNov 3 | 29 mi | Tropical storm (58 mph) | Category 1 |
| 1861 | Unnamed 1861 stormSep 28 | 12 mi | Tropical storm (58 mph) | Category 1 |
| 1858 | Unnamed 1858 stormSep 16 | 11 mi | Tropical storm (72 mph) | Category 2 |
| 1851 | Unnamed 1851 stormOct 19 | 59 mi | Tropical storm (46 mph) | Tropical storm |
Strength is the sustained wind on the track at the closest point, which is not the wind felt in Merrimack: a hurricane's worst winds sit within a few dozen miles of its centre, and inland cities are usually past that.
Tornadoes within 25 miles of Merrimack
By decade
- 2000s1
- 1990s1
- 1980s3
- 1970s8(2 EF3+)
- 1960s16
- 1950s7
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Oct 3, 1970 | F3 | 20 mi | 35.4 mi | 1 / 0 |
| Sep 29, 1974 | F3 | 23 mi | 0.1 mi | 0 / 1 |
| Jul 24, 2008 | EF2 | 23 mi | 50.46 mi | 1 / 2 |
| Jul 3, 1997 | F2 | 18 mi | 2 mi | 0 / 0 |
| Jul 21, 1972 | F2 | 13 mi | 7.6 mi | 0 / 4 |
| Jul 17, 1968 | F2 | 15 mi | 0.1 mi | 0 / 0 |
| Aug 28, 1965 | F2 | 14 mi | 2 mi | 0 / 0 |
| Jun 9, 1963 | F2 | 5 mi | 10 mi | 0 / 0 |
| Jul 2, 1961 | F2 | 12 mi | 5.1 mi | 0 / 1 |
| Jul 2, 1961 | F2 | 19 mi | 2 mi | 0 / 0 |
| Aug 21, 1951 | F2 | 19 mi | 4.9 mi | 0 / 0 |
| Aug 21, 1951 | F2 | 22 mi | 9.3 mi | 0 / 0 |
The strongest 12 of 36, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in Merrimack
The Storm Prediction Center has 76 hail reports within 10 miles of Merrimack since 1963, made on 42 separate days. Of these, 38 were 1 inch across or larger, and one reached 2 inches. The largest, 2 inches (hen egg size), fell on July 11, 1980. The most recent report is from September 6, 2025. June has the most reports, 27.
Source: NOAA Storm Prediction Center severe weather reports, data through 2025.
Weather by month in Merrimack
The nearest NOAA station with 1991–2020 climate normals is Nashua 2 NNW, NH, 5 miles southeast of Merrimack at 135 feet. July is the warmest, with an average high of 84°F and low of 61°F; January is the coolest, at 34°F and 14°F. October is the wettest at 4.8 inches of precipitation on average and February the driest at 3.2 inches; the year adds up to 48.2 inches over 89 days with at least a tenth of an inch. June to November, the hurricane season months, bring 51% of the year's precipitation (24.7 of 48.2 inches); the other six months are drier. September has brought the most of the 42 tropical systems that passed within 75 miles (16); a normal September there has highs of 75°F and 4.1 inches of precipitation. Highs reach 90°F on about 15 days a year, almost all from June to September. Lows fall below freezing on about 155 nights a year. Snowfall averages 52.9 inches a year, most of it in January. That 48.2 inches is more than at 29 of the 39 New Hampshire stations used on this site (74%). Amherst, 5 miles west, has its own station (E Milford, NH): 47.1 inches a year, 1.1 less than here, and a July average high of 83°F against 84°F.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" | Snow in |
|---|---|---|---|---|---|
| Jan | 34 | 14 | 3.4 | 7 | 14.7 |
| Feb | 37 | 15 | 3.2 | 7 | 14.5 |
| Mar | 45 | 23 | 4.3 | 7 | 10.1 |
| Apr | 59 | 34 | 4.2 | 8 | 0.7 |
| May | 70 | 46 | 3.9 | 8 | 0.0 |
| Jun | 78 | 56 | 4.3 | 8 | 0.0 |
| Jul | 84 | 61 | 3.7 | 7 | 0.0 |
| Aug | 83 | 59 | 3.9 | 7 | 0.0 |
| Sep | 75 | 51 | 4.1 | 6 | 0.0 |
| Oct | 63 | 39 | 4.8 | 8 | 0.0 |
| Nov | 51 | 30 | 3.9 | 8 | 1.7 |
| Dec | 40 | 21 | 4.5 | 8 | 11.2 |
| Year | 60 | 37 | 48.2 | 89 | 52.9 |
Averages for 1991–2020 at Nashua 2 NNW, NH (135 ft), from NOAA NCEI U.S. Climate Normals. Normals describe the station; the farther a place is from it, and the bigger the difference in height, the more its weather can differ.
Floods, thunderstorm wind and lightning near Merrimack
Since 1996, the National Weather Service has logged 144 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Merrimack: 112 thunderstorm wind reports, 15 flash floods, 10 floods and 7 lightning strikes. They killed 1 person and injured 1, and the NWS estimated $3.4 million in property and crop damage. The strongest thunderstorm gust on record here was 110 mph, on September 6, 2014. July has had the most flash floods, 5 of 15. Of the 141 New Hampshire cities on this site with a flash flood on record, 104 have had fewer than Merrimack.
July 6, 1999: thunderstorm wind 6 miles from the centre of Merrimack — 1 killed.
July 1, 2015: thunderstorm wind 7 miles from the centre of Merrimack — 1 injured.
February 25, 2010: flood 10 miles from the centre of Merrimack — $1.7 million damage.
Source: NOAA NCEI Storm Events Database, events whose starting point is on record, 1996 to June 30, 2026. Damage is the NWS estimate in the dollars of the year, not insured losses, and NWS notes that some reports are unverified.
Flood insurance claims, disaster declarations and FEMA risk ratings
Flood insurance policyholders in Merrimack's ZIP code 03054 have filed 61 claims with the National Flood Insurance Program since 1979, and were paid $1.3 million for buildings and contents, in the dollars of each year. The most came from Flooding in 1987: 10 claims (16% of all) and $107,000. The year with the most claims was 2007, with 17. 25% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 60 New Hampshire cities on this site with 10 or more claims, 47 have fewer than Merrimack.
| Event | Claims | Paid |
|---|---|---|
| Flooding1987 | 10 | $107,000 |
Hillsborough County, which includes Merrimack, has been named in 31 federal disaster or emergency declarations since 1973, 19 of them major disasters (by incident: 13 severe storms, 6 snowstorms, 5 floods, 4 hurricanes). The latest major disaster declaration was Covid-19 Pandemic, on April 3, 2020. FEMA's National Risk Index gives Hillsborough County a Relatively Moderate rating for natural hazard risk overall; by hazard: Relatively High for strong wind and lightning; Relatively Moderate for hurricanes, tornadoes and inland flooding; Relatively Low for hail and heat waves. It models the county's expected loss from all 18 hazards it covers at $120.3 million a year, the highest of 10 New Hampshire counties; of the hazards above, the largest share, $76.4 million (63%), is from inland flooding.
Claims: FEMA, OpenFEMA Dataset FIMA NFIP Redacted Claims – v3, summed over ZIP codes; payments in the dollars of each year, not adjusted for inflation. Declarations: Disaster Declarations Summaries – v2, by county. Retrieved October 25, 2026. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Risk ratings: FEMA, National Risk Index county table, December 2025 (v1.20), retrieved October 26, 2026; ratings compare counties nationwide, are meant for planning and are no substitute for a local risk assessment. This product uses the Federal Emergency Management Agency's National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
What counts as a pass, the distances and the sources: how this storm history is built.