Keene, New Hampshire climate: Normal weather by month, frost dates and records
Keene's normal year runs from 10°F January nights to 82°F July afternoons, with 46.1 inches of precipitation and 60 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.4°C, January lows of −12°C, July highs of 28°C, 1,171 mm of precipitation a year.
- NOAA stationKeene
- Station IDUSC00274399
- Location42.94°N 72.32°W
- Elevation511 ft (156 m)
- From the center1 miles
- Population23,036
On October 23, the normal high in Keene is 57°F and the normal low 33°F, and the chance of measurable rain or snow is 36%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Keene.
- Jan 30° 10°
- Feb 34° 11°
- Mar 43° 20°
- Apr 57° 30°
- May 69° 41°
- Jun 77° 51°
- Jul 82° 56°
- Aug 81° 54°
- Sep 73° 47°
- Oct 60° 36°
- Nov 47° 27°
- Dec 36° 18°
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 Keene each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 10°F. The most precipitation falls in October (4.86 in), the least in February (2.77 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. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 30°F | 10°F | 20.4°F | 3.12 | 15.2 | 12 | <1 | 30 | 9 h 20 min |
| February | 34°F | 11°F | 22.8°F | 2.77 | 14.4 | 10 | <1 | 27 | 10 h 30 min |
| March | 43°F | 20°F | 31.3°F | 3.35 | 11.0 | 11 | <1 | 28 | 11 h 50 min |
| April | 57°F | 30°F | 43.3°F | 3.39 | 2.2 | 11 | <1 | 19 | 13 h 20 min |
| May | 69°F | 41°F | 54.8°F | 3.77 | 0.0 | 13 | 1 | 5 | 14 h 40 min |
| June | 77°F | 51°F | 63.8°F | 4.41 | 0.0 | 12 | 2 | <1 | 15 h 20 min |
| July | 82°F | 56°F | 69.0°F | 4.49 | 0.0 | 12 | 4 | <1 | 15 h |
| August | 81°F | 54°F | 67.5°F | 4.28 | 0.0 | 10 | 3 | <1 | 14 h |
| September | 73°F | 47°F | 60.1°F | 4.26 | 0.0 | 10 | 1 | 1 | 12 h 30 min |
| October | 60°F | 36°F | 47.8°F | 4.86 | 0.2 | 12 | <1 | 13 | 11 h 10 min |
| November | 47°F | 27°F | 36.7°F | 3.49 | 2.4 | 11 | <1 | 23 | 9 h 50 min |
| December | 36°F | 18°F | 26.7°F | 3.92 | 14.4 | 12 | <1 | 29 | 9 h |
| Year (annual) | 57°F | 33°F | 45.4°F | 46.11 | 59.8 | 134 | 11 | 174 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −12°C | −6.4°C | 79 mm | 39 cm |
| February | 1°C | −11°C | −5.1°C | 70 mm | 37 cm |
| March | 6°C | −7°C | −0.4°C | 85 mm | 28 cm |
| April | 14°C | −1°C | 6.3°C | 86 mm | 6 cm |
| May | 20°C | 5°C | 12.7°C | 96 mm | 0 cm |
| June | 25°C | 10°C | 17.7°C | 112 mm | 0 cm |
| July | 28°C | 13°C | 20.6°C | 114 mm | 0 cm |
| August | 27°C | 12°C | 19.7°C | 109 mm | 0 cm |
| September | 23°C | 8°C | 15.6°C | 108 mm | 0 cm |
| October | 15°C | 2°C | 8.8°C | 123 mm | 1 cm |
| November | 8°C | −3°C | 2.6°C | 89 mm | 6 cm |
| December | 2°C | −8°C | −2.9°C | 100 mm | 37 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00274399; 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 Keene?
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 USC00274399.
When is the last frost in Keene?
In Keene, the last spring frost (32°F) comes after May 14 in half of years and after May 28 in one year in ten; the first autumn frost comes before October 1 in half of years and before September 18 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 141 year in 10 after May 28; 9 in 10 after April 30
- First autumn frost, half of years before
- October 11 year in 10 before September 18; 9 in 10 before October 14
NOAA puts the median frost-free season at 138 days, and the season without a hard freeze (28°F) at 160 days.
A hard freeze (28°F) comes after May 2 in half of springs and before October 10 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Keene in zone 5b in ZIP code 03431. By the map's own method, the average of each year's coldest night over 1991-2020, Keene's NOAA station is in zone 5b: the coldest night of a typical year reaches −13°F (28 complete years).
Frost dates for every NOAA station in New Hampshire · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00274399; 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 in Keene?
In a normal year in Keene, 11 days a year reach 90°F, 174 nights fall to 32°F or colder and 134 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 174a normal year
- Days that stay below freezing
- 41high of 32°F or less
- Days with 0.01 inch of precipitation
- 134a normal year
- Days with 1 inch of snow or more
- 17a normal year
The highest temperature in this station's record (since 1893) is 104°F, on July 3, 1911; the lowest is −35°F, on February 20, 1936.
The wettest calendar year on that record is 2005, with 59.17 in; the snowiest season is 1966–67, with 99.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00274399; records: ACIS (NOAA Regional Climate Centers), station USC00274399. Records use complete months only; a month missing more than three days is left out.
How sunny is Keene?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Keene, 3.8 kWh per square metre a day. August is the sunniest month (77%) and December the cloudiest (62%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 66% | 1.8 |
| February | 67% | 2.6 |
| March | 68% | 3.7 |
| April | 68% | 4.7 |
| May | 68% | 5.3 |
| June | 71% | 5.7 |
| July | 77% | 6.0 |
| August | 77% | 5.3 |
| September | 76% | 4.3 |
| October | 67% | 2.7 |
| November | 68% | 1.9 |
| December | 62% | 1.4 |
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 Keene need?
A normal year in Keene brings 7,501 heating degree days, 40% more than the median U.S. place (5,373), and 375 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 2,165 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,383 | 0 |
| February | 1,180 | 0 |
| March | 1,043 | 0 |
| April | 651 | 1 |
| May | 329 | 13 |
| June | 100 | 64 |
| July | 22 | 144 |
| August | 38 | 114 |
| September | 185 | 38 |
| October | 537 | 2 |
| November | 848 | 0 |
| December | 1,187 | 0 |
| Year (annual) | 7,501 | 375 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00274399. 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 Keene been warmer than normal lately?
2025 averaged 45.9°F, 0.5°F above the 1991-2020 normal of 45.4°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 47.3°F | +1.9°F | 57.44 | 38.0 |
| 2022 | 46.5°F | +1.1°F | 43.71 | 43.3 |
| 2023 | 48.0°F | +2.6°F | 54.36 | – |
| 2024 | 48.1°F | +2.7°F | 41.04 | 42.9 |
| 2025 | 45.9°F | +0.5°F | 45.00 | 52.3 |
Over 123 complete years from 1894 to 2025, the station's annual mean temperature rose at a fitted 3.3°F per century (+0.18°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00274399; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Keene's climate compare?
Keene is warmer than 11 of the other 27 places with their own NOAA record in New Hampshire, and wetter than 17. Across the 7,247 U.S. stations with normals, its annual mean of 45.4°F is warmer than 21%.
In the Köppen classification computed from these normals, Keene 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 Keene share this climate record?
5 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.
- Brattleboro, VT11,975 people · 13 mi SW
- West Swanzey, NH1,227 people · 5 mi S
- Marlborough, NH2,193 people · 6 mi E
- Northfield, MA2,880 people · 16 mi S
- Algiers, VT182 people · 15 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.
Questions about Keene's climate
What is the coldest month in Keene?
January, with a normal high of 30°F and a normal low of 10°F. The warmest is July (82°F by day, 56°F at night).
Does it snow in Keene?
Yes: 60 inches in a normal year, falling on 29 days with 0.1 inch or more, the most in January (15.2 inches).
What is the rainiest month in Keene?
October, with 4.86 in of precipitation in a normal year; the driest is February with 2.77 in.
What plant hardiness zone is Keene in?
The USDA's 2023 map puts Keene in zone 5b in ZIP code 03431. By the same method at Keene's NOAA station, the coldest night of a typical year reaches −13°F (28 years, 1991-2020): zone 5b.
How late can frost come in Keene?
In half of years the last 32°F night comes after May 14; in one year in ten it comes after May 28. Waiting until May 28 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Keene in OctoberThis month day by day, its records and recent years
- New Hampshire climateThe statewide normals and every place in the state
- Walpole, NH9 miles from this station, 46.0°F a year
- Jaffrey Silver Ranch Airpark, NH19 miles from this station, 47.0°F a year
- Jaffrey, NH19 miles from this station, 46.4°F a year
- Tully Lake, MA21 miles from this station, 49.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made