Greenville, Ohio climate: Normal weather by month, frost dates and records
Greenville's normal year runs from 19°F January nights to 85°F July afternoons, with 40.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 11.1°C, January lows of −7°C, July highs of 29°C, 1,023 mm of precipitation a year.
- NOAA stationGreenville Water Treatment Plant
- Station IDUSC00333375
- Location40.10°N 84.65°W
- Elevation1,030 ft (314 m)
- From the center2 miles
- Population12,701
On October 14, the normal high in Greenville is 67°F and the normal low 43°F, and the chance of measurable rain or snow is 30%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Greenville.
- Jan 35° 19°
- Feb 39° 21°
- Mar 50° 30°
- Apr 63° 40°
- May 73° 52°
- Jun 82° 61°
- Jul 85° 64°
- Aug 83° 61°
- Sep 78° 53°
- Oct 66° 42°
- Nov 52° 33°
- Dec 40° 25°
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 85°F; January the coldest, with normal lows of 19°F. The most precipitation falls in June (4.42 in), the least in February (2.23 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 35°F | 19°F | 27.0°F | 2.84 | 12 | <1 | 28 | 9 h 40 min |
| February | 39°F | 21°F | 30.2°F | 2.23 | 10 | <1 | 24 | 10 h 40 min |
| March | 50°F | 30°F | 39.9°F | 3.23 | 11 | <1 | 20 | 11 h 50 min |
| April | 63°F | 40°F | 51.6°F | 4.18 | 13 | <1 | 7 | 13 h 10 min |
| May | 73°F | 52°F | 62.5°F | 4.31 | 13 | <1 | <1 | 14 h 20 min |
| June | 82°F | 61°F | 71.2°F | 4.42 | 12 | 3 | <1 | 15 h |
| July | 85°F | 64°F | 74.1°F | 3.95 | 10 | 4 | <1 | 14 h 50 min |
| August | 83°F | 61°F | 72.2°F | 3.40 | 8 | 3 | <1 | 13 h 50 min |
| September | 78°F | 53°F | 65.7°F | 2.75 | 8 | 2 | <1 | 12 h 30 min |
| October | 66°F | 42°F | 54.0°F | 2.90 | 9 | <1 | 5 | 11 h 10 min |
| November | 52°F | 33°F | 42.1°F | 3.17 | 9 | <1 | 17 | 10 h |
| December | 40°F | 25°F | 32.2°F | 2.88 | 10 | <1 | 25 | 9 h 20 min |
| Year (annual) | 62°F | 42°F | 51.9°F | 40.26 | 125 | 12 | 126 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 2°C | −7°C | −2.8°C | 72 mm |
| February | 4°C | −6°C | −1.0°C | 57 mm |
| March | 10°C | −1°C | 4.4°C | 82 mm |
| April | 17°C | 5°C | 10.9°C | 106 mm |
| May | 23°C | 11°C | 16.9°C | 109 mm |
| June | 28°C | 16°C | 21.8°C | 112 mm |
| July | 29°C | 18°C | 23.4°C | 100 mm |
| August | 29°C | 16°C | 22.3°C | 86 mm |
| September | 26°C | 12°C | 18.7°C | 70 mm |
| October | 19°C | 6°C | 12.2°C | 74 mm |
| November | 11°C | 0°C | 5.6°C | 81 mm |
| December | 4°C | −4°C | 0.1°C | 73 mm |
NOAA publishes no 1991-2020 snowfall normal for this station, and no record within 25 miles keeps one, so snow is left out here rather than estimated.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00333375; 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 May, June, July, August, September and October. Of those, August has the fewest days with rain (8).
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 USC00333375.
When is the last frost in Greenville?
In Greenville, the last spring frost (32°F) comes after April 21 in half of years and after May 7 in one year in ten; the first autumn frost comes before October 20 in half of years and before October 6 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 211 year in 10 after May 7; 9 in 10 after April 7
- First autumn frost, half of years before
- October 201 year in 10 before October 6; 9 in 10 before November 1
NOAA puts the median frost-free season at 180 days, and the season without a hard freeze (28°F) at 203 days.
A hard freeze (28°F) comes after April 9 in half of springs and before October 31 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Greenville in zone 6a in ZIP code 45331, 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 6a: the coldest night of a typical year reaches −10°F (27 complete years).
Frost dates for every NOAA station in Ohio · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00333375; 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, 12 days a year reach 90°F, 126 nights fall to 32°F or colder and 125 days bring measurable precipitation.
- Days at 90°F or more
- 12a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 126a normal year
- Days that stay below freezing
- 39high of 32°F or less
- Days with 0.01 inch of precipitation
- 125a normal year
The highest temperature in this station's record (since 1893) is 105°F, on July 21, 1934; the lowest is −33°F, on January 19, 1994.
The wettest calendar year on that record is 2011, with 52.30 in; the snowiest season is 1950–51, with 60.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00333375; records: ACIS (NOAA Regional Climate Centers), station USC00333375. Records use complete months only; a month missing more than three days is left out.
How sunny is Greenville?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Greenville, 3.9 kWh per square metre a day. August is the sunniest month (81%) and December the cloudiest (57%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 58% | 1.7 |
| February | 63% | 2.6 |
| March | 65% | 3.6 |
| April | 69% | 4.8 |
| May | 72% | 5.5 |
| June | 77% | 6.2 |
| July | 80% | 6.2 |
| August | 81% | 5.6 |
| September | 78% | 4.5 |
| October | 70% | 3.0 |
| November | 67% | 2.1 |
| December | 57% | 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 Greenville need?
A normal year in Greenville brings 5,672 heating degree days, 6% more than the median U.S. place (5,373), and 933 cooling degree days, 3% more 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 3,360 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,176 | 0 |
| February | 973 | 0 |
| March | 779 | 1 |
| April | 413 | 10 |
| May | 156 | 77 |
| June | 21 | 209 |
| July | 2 | 284 |
| August | 6 | 230 |
| September | 84 | 106 |
| October | 357 | 16 |
| November | 687 | 0 |
| December | 1,017 | 0 |
| Year (annual) | 5,672 | 933 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00333375. 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 51.6°F, 0.3°F below the 1991-2020 normal of 51.9°F. 3 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 52.9°F | +1.0°F | 47.79 |
| 2023 | 53.0°F | +1.1°F | 35.60 |
| 2024 | 54.4°F | +2.5°F | 41.07 |
| 2025 | 51.6°F | −0.3°F | 38.17 |
Over 120 complete years from 1887 to 2025, the station's annual mean temperature rose at a fitted 1.1°F per century (+0.06°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00333375; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Greenville's climate compare?
Greenville is warmer than 58 of the other 98 places with their own NOAA record in Ohio, and wetter than 30. Across the 7,247 U.S. stations with normals, its annual mean of 51.9°F is warmer than 49%.
In the Köppen classification computed from these normals, Greenville 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 Greenville share this climate record?
9 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.
- Union City, IN3,435 people · 11 mi NW
- Versailles, OH2,719 people · 12 mi NE
- Arcanum, OH2,333 people · 9 mi SE
- Lynn, IN946 people · 16 mi W
- Wayne Lakes, OH684 people · 6 mi S
- Gettysburg, OH462 people · 8 mi E
- Pitsburg, OH377 people · 12 mi SE
- Whitewater, IN71 people · 15 mi SW
- Spartanburg, IN55 people · 11 mi W
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 Greenville's climate
What is the coldest month in Greenville?
January, with a normal high of 35°F and a normal low of 19°F. The warmest is July (85°F by day, 64°F at night).
What is the rainiest month in Greenville?
June, with 4.42 in of precipitation in a normal year; the driest is February with 2.23 in.
What plant hardiness zone is Greenville in?
The USDA's 2023 map puts Greenville in zone 6a in ZIP code 45331, the nearest ZIP area. By the same method at Greenville's NOAA station, the coldest night of a typical year reaches −10°F (27 years, 1991-2020): zone 6a.
How late can frost come in Greenville?
In half of years the last 32°F night comes after April 21; in one year in ten it comes after May 7. Waiting until May 7 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Ohio climateThe statewide normals and every place in the state
- Winchester, IN15 miles from this station, 50.8°F a year
- Richmond, IN21 miles from this station, 52.3°F a year
- Piqua, OH22 miles from this station, 52.7°F a year
- Eaton, OH25 miles from this station, 51.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made