Greenville, Maine climate: Normal weather by month, frost dates and records
Greenville's normal year runs from 5°F January nights to 75°F July afternoons, with 44.5 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 5.1°C, January lows of −15°C, July highs of 24°C, 1,130 mm of precipitation a year.
- NOAA stationGreenville Maine Forestry Service
- Station IDUSW00094626
- Location45.46°N 69.60°W
- Elevation1,037 ft (316 m)
- Population (town)1,677
- Census place883
On October 14, the normal high in Greenville is 53°F and the normal low 38°F, and the chance of measurable rain or snow is 43%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Greenville.
- Jan 23° 5°
- Feb 25° 7°
- Mar 34° 17°
- Apr 46° 30°
- May 62° 41°
- Jun 70° 51°
- Jul 75° 57°
- Aug 74° 56°
- Sep 66° 48°
- Oct 53° 37°
- Nov 39° 27°
- Dec 28° 15°
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 Greenville each month?
July is the warmest month, with normal highs of 75°F; January the coldest, with normal lows of 5°F. The most precipitation falls in October (5.00 in), the least in February (2.41 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 23°F | 5°F | 14.2°F | 2.98 | 13 | <1 | 31 | 9 h |
| February | 25°F | 7°F | 16.3°F | 2.41 | 12 | <1 | 28 | 10 h 20 min |
| March | 34°F | 17°F | 25.6°F | 3.19 | 13 | <1 | 29 | 11 h 50 min |
| April | 46°F | 30°F | 38.0°F | 3.59 | 13 | <1 | 20 | 13 h 30 min |
| May | 62°F | 41°F | 51.4°F | 3.59 | 14 | <1 | 2 | 14 h 50 min |
| June | 70°F | 51°F | 60.7°F | 4.04 | 14 | <1 | <1 | 15 h 40 min |
| July | 75°F | 57°F | 66.3°F | 4.01 | 14 | <1 | <1 | 15 h 20 min |
| August | 74°F | 56°F | 64.8°F | 3.96 | 13 | <1 | <1 | 14 h 10 min |
| September | 66°F | 48°F | 57.2°F | 3.44 | 11 | <1 | <1 | 12 h 40 min |
| October | 53°F | 37°F | 44.9°F | 5.00 | 14 | <1 | 8 | 11 h |
| November | 39°F | 27°F | 32.9°F | 3.96 | 14 | <1 | 22 | 9 h 30 min |
| December | 28°F | 15°F | 21.5°F | 4.33 | 16 | <1 | 30 | 8 h 40 min |
| Year (annual) | 50°F | 33°F | 41.1°F | 44.50 | 160 | 1 | 171 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −5°C | −15°C | −9.9°C | 76 mm |
| February | −4°C | −14°C | −8.7°C | 61 mm |
| March | 1°C | −8°C | −3.6°C | 81 mm |
| April | 8°C | −1°C | 3.3°C | 91 mm |
| May | 16°C | 5°C | 10.8°C | 91 mm |
| June | 21°C | 11°C | 15.9°C | 103 mm |
| July | 24°C | 14°C | 19.1°C | 102 mm |
| August | 23°C | 13°C | 18.2°C | 101 mm |
| September | 19°C | 9°C | 14.0°C | 87 mm |
| October | 11°C | 3°C | 7.2°C | 127 mm |
| November | 4°C | −3°C | 0.5°C | 101 mm |
| December | −2°C | −10°C | −5.8°C | 110 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Moosehead (10 miles away), gets 98 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00094626; 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 Greenville?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, September has the fewest days with rain (11).
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 USW00094626.
When is the last frost in Greenville?
In Greenville, the last spring frost (32°F) comes after May 7 in half of years and after May 20 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 71 year in 10 after May 20; 9 in 10 after April 27
- 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 153 days, and the season without a hard freeze (28°F) at 177 days.
A hard freeze (28°F) comes after April 28 in half of springs and before October 22 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Greenville in zone 4b in ZIP code 04442, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Greenville's NOAA station is in zone 5a: the coldest night of a typical year reaches −15°F (17 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 Maine · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00094626; 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 Greenville?
In a normal year in Greenville, 1 day a year reaches 90°F, 171 nights fall to 32°F or colder and 160 days bring measurable precipitation.
- 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
- 171a normal year
- Days that stay below freezing
- 89high of 32°F or less
- Days with 0.01 inch of precipitation
- 160a normal year
The highest temperature in this station's record (since 1920) is 96°F, on August 14, 1944; the lowest is −42°F, on February 2, 1962.
The wettest calendar year on that record is 2005, with 68.95 in; the snowiest season is 1968–69, with 221.7 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00094626; records: ACIS (NOAA Regional Climate Centers), station USW00094626. Records use complete months only; a month missing more than three days is left out.
How sunny is Greenville?
Over a year 68% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Greenville, 3.5 kWh per square metre a day. September is the sunniest month (74%) and December the cloudiest (59%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 64% | 1.5 |
| February | 66% | 2.4 |
| March | 69% | 3.6 |
| April | 67% | 4.6 |
| May | 65% | 5.1 |
| June | 67% | 5.5 |
| July | 72% | 5.6 |
| August | 73% | 5.0 |
| September | 74% | 4.0 |
| October | 65% | 2.5 |
| November | 61% | 1.5 |
| December | 59% | 1.1 |
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 Greenville need?
A normal year in Greenville brings 8,860 heating degree days, 65% more than the median U.S. place (5,373), and 200 cooling degree days, 78% 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 1,698 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,576 | 0 |
| February | 1,364 | 0 |
| March | 1,221 | 0 |
| April | 812 | 0 |
| May | 427 | 6 |
| June | 160 | 31 |
| July | 45 | 85 |
| August | 67 | 60 |
| September | 251 | 17 |
| October | 624 | 1 |
| November | 963 | 0 |
| December | 1,350 | 0 |
| Year (annual) | 8,860 | 200 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00094626. 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 Greenville been warmer than normal lately?
2025 averaged 41.3°F, 0.2°F above the 1991-2020 normal of 41.1°F. 4 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 43.9°F | +2.8°F | 34.11 |
| 2022 | 43.1°F | +2.0°F | 53.68 |
| 2024 | 44.6°F | +3.5°F | 44.62 |
| 2025 | 41.3°F | +0.2°F | – |
Source: observed years: ACIS, station USW00094626. A year counts only with all twelve months complete.
How does Greenville's climate compare?
Greenville is warmer than 8 of the other 41 places with their own NOAA record in Maine, and wetter than 15. Across the 7,247 U.S. stations with normals, its annual mean of 41.1°F is warmer than 8%.
In the Köppen classification computed from these normals, Greenville 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.
Questions about Greenville's climate
What is the coldest month in Greenville?
January, with a normal high of 23°F and a normal low of 5°F. The warmest is July (75°F by day, 57°F at night).
Does it snow in Greenville?
Yes. NOAA publishes no 1991-2020 snowfall normal for Greenville's NOAA station; the nearest record that keeps one, Moosehead (10 miles away), records 98 inches of snow in a normal year.
What is the rainiest month in Greenville?
October, with 5.00 in of precipitation in a normal year; the driest is February with 2.41 in.
What plant hardiness zone is Greenville in?
The USDA's 2023 map puts Greenville in zone 4b in ZIP code 04442, the nearest ZIP area. By the same method at Greenville's NOAA station, the coldest night of a typical year reaches −15°F (17 years, 1991-2020): zone 5a.
How late can frost come in Greenville?
In half of years the last 32°F night comes after May 7; in one year in ten it comes after May 20. Waiting until May 20 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Maine climateThe statewide normals and every place in the state
- Moosehead, ME11 miles from this station, 40.1°F a year
- Brassua Dam, ME17 miles from this station, 39.6°F a year
- Sebec Lake, ME23 miles from this station, 41.4°F a year
- Barnard, ME25 miles from this station, 42.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made