Mount Sunapee, New Hampshire climate: Climate normals at a NOAA weather station
Mount Sunapee's normal year runs from 13°F January nights to 79°F July afternoons, with 48.5 inches of precipitation and 85 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.5°C, January lows of −11°C, July highs of 26°C, 1,231 mm of precipitation a year.
- NOAA stationMount Sunapee
- Station IDUSC00275629
- Location43.33°N 72.08°W
- Elevation1,275 ft (389 m)
On October 22, the normal high in Mount Sunapee is 54°F and the normal low 36°F, and the chance of measurable rain or snow is 38%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Mount Sunapee.
- Jan 29° 13°
- Feb 32° 15°
- Mar 40° 22°
- Apr 53° 33°
- May 66° 44°
- Jun 75° 54°
- Jul 79° 59°
- Aug 77° 57°
- Sep 70° 50°
- Oct 57° 39°
- Nov 45° 29°
- Dec 34° 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 at Mount Sunapee each month?
July is the warmest month, with normal highs of 79°F; January the coldest, with normal lows of 13°F. The most precipitation falls in October (5.52 in), the least in February (3.07 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 29°F | 13°F | 20.8°F | 3.34 | 18.4 | 11 | <1 | 30 | 9 h 20 min |
| February | 32°F | 15°F | 23.0°F | 3.07 | 24.6 | 8 | <1 | 27 | 10 h 30 min |
| March | 40°F | 22°F | 30.8°F | 3.74 | 12.3 | 10 | <1 | 26 | 11 h 50 min |
| April | 53°F | 33°F | 43.1°F | 4.21 | 4.7 | 10 | <1 | 14 | 13 h 20 min |
| May | 66°F | 44°F | 55.3°F | 3.91 | 0.0 | 13 | <1 | 1 | 14 h 40 min |
| June | 75°F | 54°F | 64.2°F | 4.41 | 0.0 | 14 | 1 | <1 | 15 h 20 min |
| July | 79°F | 59°F | 69.0°F | 4.42 | 0.0 | 13 | 1 | <1 | 15 h 10 min |
| August | 77°F | 57°F | 67.3°F | 3.66 | 0.0 | 11 | <1 | <1 | 14 h |
| September | 70°F | 50°F | 60.2°F | 4.18 | 0.0 | 10 | <1 | <1 | 12 h 30 min |
| October | 57°F | 39°F | 47.7°F | 5.52 | 1.2 | 12 | <1 | 7 | 11 h 10 min |
| November | 45°F | 29°F | 37.0°F | 3.73 | 3.6 | 11 | <1 | 19 | 9 h 40 min |
| December | 34°F | 20°F | 27.0°F | 4.27 | 20.6 | 12 | <1 | 28 | 9 h |
| Year (annual) | 55°F | 36°F | 45.5°F | 48.46 | 85.4 | 134 | 2 | 152 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −2°C | −11°C | −6.2°C | 85 mm | 47 cm |
| February | 0°C | −10°C | −5.0°C | 78 mm | 62 cm |
| March | 4°C | −6°C | −0.7°C | 95 mm | 31 cm |
| April | 12°C | 0°C | 6.2°C | 107 mm | 12 cm |
| May | 19°C | 7°C | 12.9°C | 99 mm | 0 cm |
| June | 24°C | 12°C | 17.9°C | 112 mm | 0 cm |
| July | 26°C | 15°C | 20.6°C | 112 mm | 0 cm |
| August | 25°C | 14°C | 19.6°C | 93 mm | 0 cm |
| September | 21°C | 10°C | 15.7°C | 106 mm | 0 cm |
| October | 14°C | 4°C | 8.7°C | 140 mm | 3 cm |
| November | 7°C | −2°C | 2.8°C | 95 mm | 9 cm |
| December | 1°C | −7°C | −2.8°C | 108 mm | 52 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00275629; 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.
Which months are mildest at Mount Sunapee?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (10).
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 USC00275629.
When is the last frost at Mount Sunapee?
In Mount Sunapee, the last spring frost (32°F) comes after May 2 in half of years and after May 17 in one year in ten; the first autumn frost comes before October 9 in half of years and before September 27 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
- May 21 year in 10 after May 17; 9 in 10 after April 21
- First autumn frost, half of years before
- October 91 year in 10 before September 27; 9 in 10 before October 24
NOAA puts the median frost-free season at 158 days, and the season without a hard freeze (28°F) at 181 days.
A hard freeze (28°F) comes after April 21 in half of springs and before October 21 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Mount Sunapee in zone 5b in ZIP code 03255, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 6a: the coldest night of a typical year reaches −9°F (18 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in New Hampshire · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00275629; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at Mount Sunapee?
In a normal year in Mount Sunapee, 2 days a year reach 90°F, 152 nights fall to 32°F or colder and 134 days bring measurable precipitation.
- Days at 90°F or more
- 2a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 152a normal year
- Days that stay below freezing
- 57high of 32°F or less
- Days with 0.01 inch of precipitation
- 134a normal year
- Days with 1 inch of snow or more
- 20a normal year
The highest temperature in this station's record (since 1957) is 98°F, on July 10, 1988; the lowest is −26°F, on January 8, 1968.
The wettest calendar year on that record is 2005, with 65.13 in; the snowiest season is 2002–03, with 135.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00275629; records: ACIS (NOAA Regional Climate Centers), station USC00275629. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Mount Sunapee?
Over a year 69% of the sunlight that would reach the ground under clear skies gets through the clouds at Mount Sunapee, 3.7 kWh per square metre a day. August is the sunniest month (76%) and December the cloudiest (57%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 63% | 1.6 |
| February | 67% | 2.5 |
| March | 68% | 3.7 |
| April | 67% | 4.6 |
| May | 67% | 5.2 |
| June | 69% | 5.6 |
| July | 75% | 5.8 |
| August | 76% | 5.2 |
| September | 75% | 4.2 |
| October | 64% | 2.6 |
| November | 64% | 1.7 |
| December | 57% | 1.2 |
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 many heating and cooling degree days does Mount Sunapee record?
A normal year at Mount Sunapee brings 7,459 heating degree days, 39% more than the median U.S. place (5,373), and 371 cooling degree days, 59% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,177 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,370 | 0 |
| February | 1,175 | 0 |
| March | 1,059 | 0 |
| April | 659 | 0 |
| May | 315 | 14 |
| June | 95 | 72 |
| July | 18 | 144 |
| August | 35 | 108 |
| September | 178 | 32 |
| October | 537 | 1 |
| November | 840 | 0 |
| December | 1,180 | 0 |
| Year (annual) | 7,459 | 371 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00275629. 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.
How does Mount Sunapee's climate compare?
Mount Sunapee is warmer than 13 of the 28 places with their own NOAA record in New Hampshire, and wetter than 24. Across the 7,247 U.S. stations with normals, its annual mean of 45.5°F is warmer than 21%.
In the Köppen classification computed from these normals, Mount Sunapee is Dfb: continental, no dry season, warm 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 Mount Sunapee share this climate record?
2 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.
- New London, NH4,460 people · 7 mi NE
- Blodgett Landing, NH102 people · 4 mi NE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Mount Sunapee's climate
What is the coldest month at Mount Sunapee?
January, with a normal high of 29°F and a normal low of 13°F. The warmest is July (79°F by day, 59°F at night).
Does it snow at Mount Sunapee?
Yes: 85 inches in a normal year, falling on 23 days with 0.1 inch or more, the most in February (24.6 inches).
What is the rainiest month at Mount Sunapee?
October, with 5.52 in of precipitation in a normal year; the driest is February with 3.07 in.
What plant hardiness zone is Mount Sunapee in?
The USDA's 2023 map puts Mount Sunapee in zone 5b in ZIP code 03255, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −9°F (18 years, 1991-2020): zone 6a.
How late can frost come at Mount Sunapee?
In half of years the last 32°F night comes after May 2; in one year in ten it comes after May 17. Waiting until May 17 leaves about a one-in-ten chance of a later frost.
Nearby and next
- New Hampshire climateThe statewide normals and every place in the state
- Newport, NH6 miles from this station, 44.3°F a year
- Bradford, NH6 miles from this station, 45.1°F a year
- Salisbury, NH17 miles from this station, 45.5°F a year
- Grafton, NH17 miles from this station, 43.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made