West Harwich, Massachusetts climate: Climate normals at a NOAA weather station
West Harwich's normal year runs from 24°F February nights to 78°F July afternoons, with 46.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.2°C, February lows of −4°C, July highs of 25°C, 1,177 mm of precipitation a year.
- NOAA stationWest Harwich
- Station IDUSC00199227
- Location41.66°N 70.12°W
- Elevation15 ft (5 m)
On October 23, the normal high in West Harwich is 59°F and the normal low 44°F.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for West Harwich.
- Jan 38° 25°
- Feb 38° 24°
- Mar 44° 30°
- Apr 52° 39°
- May 62° 48°
- Jun 71° 58°
- Jul 78° 65°
- Aug 78° 64°
- Sep 71° 57°
- Oct 62° 47°
- Nov 52° 37°
- Dec 43° 30°
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 West Harwich each month?
July is the warmest month, with normal highs of 78°F; February the coldest, with normal lows of 24°F. The most precipitation falls in December (4.83 in), the least in July (2.77 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 38°F | 25°F | 31.3°F | 3.84 | – | <1 | 23 | 9 h 30 min |
| February | 38°F | 24°F | 31.0°F | 3.68 | – | <1 | 19 | 10 h 30 min |
| March | 44°F | 30°F | 37.2°F | 4.32 | – | <1 | 18 | 11 h 50 min |
| April | 52°F | 39°F | 45.4°F | 4.10 | – | <1 | 4 | 13 h 20 min |
| May | 62°F | 48°F | 54.8°F | 3.50 | – | <1 | <1 | 14 h 30 min |
| June | 71°F | 58°F | 64.1°F | 3.29 | – | <1 | <1 | 15 h 10 min |
| July | 78°F | 65°F | 71.1°F | 2.77 | – | 1 | <1 | 15 h |
| August | 78°F | 64°F | 70.6°F | 3.36 | – | <1 | <1 | 13 h 50 min |
| September | 71°F | 57°F | 63.9°F | 3.93 | – | <1 | <1 | 12 h 30 min |
| October | 62°F | 47°F | 54.1°F | 4.72 | – | <1 | 1 | 11 h 10 min |
| November | 52°F | 37°F | 44.8°F | 4.00 | – | <1 | 9 | 9 h 50 min |
| December | 43°F | 30°F | 36.5°F | 4.83 | – | <1 | 21 | 9 h 10 min |
| Year (annual) | 57°F | 44°F | 50.4°F | 46.34 | – | 1 | 94 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 3°C | −4°C | −0.4°C | 98 mm |
| February | 3°C | −4°C | −0.6°C | 93 mm |
| March | 7°C | −1°C | 2.9°C | 110 mm |
| April | 11°C | 4°C | 7.4°C | 104 mm |
| May | 16°C | 9°C | 12.7°C | 89 mm |
| June | 21°C | 14°C | 17.8°C | 84 mm |
| July | 25°C | 18°C | 21.7°C | 70 mm |
| August | 25°C | 18°C | 21.4°C | 85 mm |
| September | 22°C | 14°C | 17.7°C | 100 mm |
| October | 16°C | 8°C | 12.3°C | 120 mm |
| November | 11°C | 3°C | 7.1°C | 102 mm |
| December | 6°C | −1°C | 2.5°C | 123 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Chatham station (8 miles away), gets 25 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00199227; 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 West Harwich?
Normal highs sit between 65°F and 85°F in 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 USC00199227.
When is the last frost at West Harwich?
In West Harwich, the last spring frost (32°F) comes after April 13 in half of years and after April 26 in one year in ten; the first autumn frost comes before November 3 in half of years and before October 22 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 131 year in 10 after April 26; 9 in 10 after April 2
- First autumn frost, half of years before
- November 31 year in 10 before October 22; 9 in 10 before November 18
NOAA puts the median frost-free season at 204 days, and the season without a hard freeze (28°F) at 230 days.
A hard freeze (28°F) comes after April 1 in half of springs and before November 17 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts West Harwich in zone 7b in ZIP code 02671, the nearest ZIP area.
Frost dates for every NOAA station in Massachusetts · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00199227; 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.
How hot and how cold does it get at West Harwich?
In a normal year in West Harwich, 1 day a year reaches 90°F and 94 nights fall to 32°F or colder.
- Days at 90°F or more
- 1a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 94a normal year
- Days that stay below freezing
- 14high of 32°F or less
Source: NOAA NCEI 1991-2020 annual normals, station USC00199227.
How sunny is it at West Harwich?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds at West Harwich, 3.9 kWh per square metre a day. August is the sunniest month (80%) and December the cloudiest (65%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 67% | 1.8 |
| February | 70% | 2.7 |
| March | 70% | 3.7 |
| April | 72% | 4.9 |
| May | 72% | 5.5 |
| June | 74% | 5.9 |
| July | 80% | 6.0 |
| August | 80% | 5.4 |
| September | 79% | 4.4 |
| October | 72% | 3.0 |
| November | 70% | 2.0 |
| December | 65% | 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 many heating and cooling degree days does West Harwich record?
A normal year at West Harwich brings 5,761 heating degree days, 7% more than the median U.S. place (5,373), and 466 cooling degree days, 49% 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 2,502 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,046 | 0 |
| February | 952 | 0 |
| March | 863 | 0 |
| April | 590 | 0 |
| May | 318 | 1 |
| June | 70 | 42 |
| July | 4 | 193 |
| August | 5 | 177 |
| September | 84 | 51 |
| October | 341 | 2 |
| November | 606 | 0 |
| December | 883 | 0 |
| Year (annual) | 5,761 | 466 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00199227. 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 West Harwich's climate compare?
West Harwich is warmer than 23 of the 35 places with their own NOAA record in Massachusetts, and wetter than 14. Across the 7,247 U.S. stations with normals, its annual mean of 50.4°F is warmer than 42%.
In the Köppen classification computed from these normals, West Harwich 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 West Harwich share this climate record?
7 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.
- Northwest Harwich, MA4,205 people · 2 mi N
- East Dennis, MA3,685 people · 5 mi NW
- Dennis Port, MA3,439 people · 1 mi W
- South Dennis, MA3,190 people · 3 mi NW
- West Dennis, MA2,586 people · 3 mi W
- Harwich Port, MA2,011 people · 3 mi E
- Harwich Center, MA1,620 people · 3 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 West Harwich's climate
What is the coldest month at West Harwich?
February, with a normal high of 38°F and a normal low of 24°F. The warmest is July (78°F by day, 65°F at night).
Does it snow at West Harwich?
Yes. NOAA publishes no 1991-2020 snowfall normal for the station; the nearest record that keeps one, Chatham station (8 miles away), records 25 inches of snow in a normal year.
What is the rainiest month at West Harwich?
December, with 4.83 in of precipitation in a normal year; the driest is July with 2.77 in.
What plant hardiness zone is West Harwich in?
The USDA's 2023 map puts West Harwich in zone 7b in ZIP code 02671, the nearest ZIP area.
How late can frost come at West Harwich?
In half of years the last 32°F night comes after April 13; in one year in ten it comes after April 26. Waiting until April 26 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Massachusetts climateThe statewide normals and every place in the state
- Chatham, MA7 miles from this station, 50.9°F a year
- Hyannis Barnstable Municipal Airport, MA9 miles from this station, 51.5°F a year
- Barnstable, MA10 miles from this station, 50.3°F a year
- East Sandwich, MA19 miles from this station, 49.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made