Nashua, New Hampshire climate: Normal weather by month, frost dates and records
Nashua's normal year runs from 14°F January nights to 85°F July afternoons, with 46.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.3°C, January lows of −10°C, July highs of 29°C, 1,175 mm of precipitation a year.
- NOAA stationNashua Cwsu
- Station IDUSC00275703
- Location42.73°N 71.48°W
- Elevation180 ft (55 m)
- From the center1 miles
- Population91,851
On October 22, the normal high in Nashua is 60°F and the normal low 36°F.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Nashua.
- Jan 35° 14°
- Feb 38° 16°
- Mar 45° 24°
- Apr 58° 35°
- May 69° 46°
- Jun 79° 56°
- Jul 85° 62°
- Aug 83° 60°
- Sep 75° 52°
- Oct 62° 39°
- Nov 51° 29°
- Dec 40° 20°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Nashua each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 14°F. The most precipitation falls in October (4.66 in), the least in January (3.00 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 35°F | 14°F | 24.2°F | 3.00 | – | <1 | 30 | 9 h 20 min |
| February | 38°F | 16°F | 26.5°F | 3.07 | – | <1 | 26 | 10 h 30 min |
| March | 45°F | 24°F | 34.7°F | 4.11 | – | <1 | 24 | 11 h 50 min |
| April | 58°F | 35°F | 46.6°F | 3.91 | – | <1 | 13 | 13 h 20 min |
| May | 69°F | 46°F | 57.8°F | 3.63 | – | 2 | 1 | 14 h 40 min |
| June | 79°F | 56°F | 67.3°F | 4.19 | – | 3 | <1 | 15 h 20 min |
| July | 85°F | 62°F | 73.1°F | 3.63 | – | 12 | <1 | 15 h |
| August | 83°F | 60°F | 71.2°F | 3.71 | – | 7 | <1 | 14 h |
| September | 75°F | 52°F | 63.7°F | 4.15 | – | 3 | 1 | 12 h 30 min |
| October | 62°F | 39°F | 50.6°F | 4.66 | – | <1 | 7 | 11 h 10 min |
| November | 51°F | 29°F | 39.8°F | 3.74 | – | <1 | 21 | 9 h 50 min |
| December | 40°F | 20°F | 29.6°F | 4.45 | – | <1 | 27 | 9 h |
| Year (annual) | 60°F | 38°F | 48.7°F | 46.25 | – | 27 | 149 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 1°C | −10°C | −4.3°C | 76 mm |
| February | 3°C | −9°C | −3.1°C | 78 mm |
| March | 7°C | −4°C | 1.5°C | 104 mm |
| April | 15°C | 2°C | 8.1°C | 99 mm |
| May | 21°C | 8°C | 14.3°C | 92 mm |
| June | 26°C | 13°C | 19.6°C | 106 mm |
| July | 29°C | 16°C | 22.8°C | 92 mm |
| August | 28°C | 15°C | 21.8°C | 94 mm |
| September | 24°C | 11°C | 17.6°C | 105 mm |
| October | 17°C | 4°C | 10.3°C | 118 mm |
| November | 10°C | −2°C | 4.3°C | 95 mm |
| December | 4°C | −7°C | −1.3°C | 113 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Nashua's own co-op station Nashua (2 mi NNW) does: 53 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USC00275703; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Nashua?
Normal highs sit between 65°F and 85°F in May, June, July, August and September.
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00275703.
When is the last frost in Nashua?
In Nashua, the last spring frost (32°F) comes after April 29 in half of years and after May 11 in one year in ten; the first autumn frost comes before October 8 in half of years and before September 28 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 291 year in 10 after May 11; 9 in 10 after April 16
- First autumn frost, half of years before
- October 81 year in 10 before September 28; 9 in 10 before October 25
NOAA puts the median frost-free season at 162 days, and the season without a hard freeze (28°F) at 185 days.
A hard freeze (28°F) comes after April 16 in half of springs and before October 20 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Nashua in zone 6a across its 4 ZIP code areas (6a in 03062, the largest).
Frost dates for every NOAA station in New Hampshire · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00275703; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Nashua ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Nashua's 4 ZIP code areas are all in zone 6a. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Nashua?
In a normal year in Nashua, 27 days a year reach 90°F and 149 nights fall to 32°F or colder.
- Days at 90°F or more
- 27a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 149a normal year
- Days that stay below freezing
- 31high of 32°F or less
Source: NOAA NCEI 1991-2020 annual normals, station USC00275703.
How sunny is Nashua?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Nashua, 3.8 kWh per square metre a day. August is the sunniest month (78%) and December the cloudiest (66%). Among the 459 U.S. places of 50,000 or more, that ranks tied 385th (with 30 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 69% | 1.8 |
| February | 70% | 2.7 |
| March | 69% | 3.7 |
| April | 69% | 4.7 |
| May | 68% | 5.3 |
| June | 71% | 5.7 |
| July | 78% | 6.0 |
| August | 78% | 5.3 |
| September | 77% | 4.3 |
| October | 68% | 2.8 |
| November | 70% | 2.0 |
| December | 66% | 1.5 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Nashua need?
A normal year in Nashua brings 6,593 heating degree days, 23% more than the median U.S. place (5,373), and 704 cooling degree days, 22% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,767 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,266 | 0 |
| February | 1,078 | 0 |
| March | 939 | 0 |
| April | 558 | 4 |
| May | 255 | 30 |
| June | 54 | 123 |
| July | 8 | 260 |
| August | 11 | 203 |
| September | 121 | 81 |
| October | 449 | 3 |
| November | 756 | 0 |
| December | 1,099 | 0 |
| Year (annual) | 6,593 | 704 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00275703. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Nashua been warmer than normal lately?
2025 averaged 48.4°F, 0.3°F below the 1991-2020 normal of 48.7°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 49.9°F | +1.2°F | 53.31 |
| 2022 | 49.4°F | +0.7°F | 39.10 |
| 2023 | 50.3°F | +1.5°F | 67.15 |
| 2024 | 50.3°F | +1.6°F | 41.51 |
| 2025 | 48.4°F | −0.3°F | 40.58 |
Source: observed years: ACIS, station USC00275703. A year counts only with all twelve months complete.
How does Nashua's climate compare?
Nashua is warmer than 26 of the other 27 places with their own NOAA record in New Hampshire, and wetter than 18. Across the 7,247 U.S. stations with normals, its annual mean of 48.7°F is warmer than 35%.
In the Köppen classification computed from these normals, Nashua is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Nashua share this climate record?
6 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Ayer, MA9,010 people · 13 mi SW
- Littleton Common, MA2,838 people · 14 mi S
- East Pepperell, MA1,984 people · 6 mi SW
- Pepperell, MA11,877 people · 7 mi SW
- Devens, MA1,871 people · 15 mi SW
- Groton, MA11,580 people · 10 mi SW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Nashua's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Nashua. This page uses Nashua Cwsu; the other differs by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Nashua (2 mi NNW) USC00275712 | 3 mi N | 135 ft | 48.7°F | 14°F | 84°F | 48.2 | 53 | April 30 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Nashua's climate
What is the coldest month in Nashua?
January, with a normal high of 35°F and a normal low of 14°F. The warmest is July (85°F by day, 62°F at night).
Does it snow in Nashua?
Yes. NOAA publishes no 1991-2020 snowfall normal for Nashua's NOAA station; Nashua's own co-op station Nashua (2 mi NNW) records 53 inches of snow in a normal year.
What is the rainiest month in Nashua?
October, with 4.66 in of precipitation in a normal year; the driest is January with 3.00 in.
What plant hardiness zone is Nashua in?
The USDA's 2023 map puts Nashua in zone 6a across its 4 ZIP code areas (6a in 03062, the largest).
How late can frost come in Nashua?
In half of years the last 32°F night comes after April 29; in one year in ten it comes after May 11. Waiting until May 11 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Nashua in OctoberThis month day by day, its records and recent years
- New Hampshire climateThe statewide normals and every place in the state
- Hudson, NH5 miles from this station, 47.9°F a year
- Lowell, MA9 miles from this station, 49.0°F a year
- East Milford, NH10 miles from this station, 47.8°F a year
- Milford, NH11 miles from this station, 47.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made