Butler, Pennsylvania climate: Normal weather by month, frost dates and records
Butler's normal year runs from 17°F January nights to 82°F July afternoons, with 43.2 inches of precipitation and 35 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.2°C, January lows of −8°C, July highs of 28°C, 1,098 mm of precipitation a year.
- NOAA stationButler (2 mi SW)
- Station IDUSC00361139
- Location40.84°N 79.92°W
- Elevation1,000 ft (305 m)
- From the center2 miles
- Population13,010
On October 12, the normal high in Butler is 64°F and the normal low 40°F, and the chance of measurable rain or snow is 42%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Butler.
- Jan 34° 17°
- Feb 37° 18°
- Mar 46° 25°
- Apr 60° 35°
- May 70° 45°
- Jun 78° 54°
- Jul 82° 58°
- Aug 81° 57°
- Sep 74° 50°
- Oct 62° 39°
- Nov 50° 30°
- Dec 39° 23°
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 Butler each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 17°F. The most precipitation falls in June (4.33 in), the least in February (2.66 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 | 34°F | 17°F | 25.8°F | 3.36 | 11.3 | 18 | <1 | 27 | 9 h 30 min |
| February | 37°F | 18°F | 27.8°F | 2.66 | 9.7 | 15 | <1 | 25 | 10 h 40 min |
| March | 46°F | 25°F | 35.8°F | 3.28 | 5.3 | 14 | <1 | 23 | 11 h 50 min |
| April | 60°F | 35°F | 47.3°F | 3.50 | 0.6 | 15 | <1 | 12 | 13 h 20 min |
| May | 70°F | 45°F | 57.4°F | 3.80 | 0.0 | 15 | <1 | 2 | 14 h 30 min |
| June | 78°F | 54°F | 66.1°F | 4.33 | 0.0 | 13 | 1 | <1 | 15 h 10 min |
| July | 82°F | 58°F | 70.0°F | 4.16 | 0.0 | 12 | 3 | <1 | 14 h 50 min |
| August | 81°F | 57°F | 68.8°F | 4.02 | 0.0 | 11 | 2 | <1 | 13 h 50 min |
| September | 74°F | 50°F | 61.9°F | 4.09 | 0.0 | 11 | 1 | <1 | 12 h 30 min |
| October | 62°F | 39°F | 50.4°F | 3.30 | 0.1 | 13 | <1 | 6 | 11 h 10 min |
| November | 50°F | 30°F | 39.7°F | 3.34 | 1.1 | 14 | <1 | 19 | 10 h |
| December | 39°F | 23°F | 31.2°F | 3.37 | 6.8 | 16 | <1 | 26 | 9 h 20 min |
| Year (annual) | 59°F | 38°F | 48.5°F | 43.21 | 34.9 | 168 | 7 | 140 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 1°C | −8°C | −3.4°C | 85 mm | 29 cm |
| February | 3°C | −8°C | −2.3°C | 68 mm | 25 cm |
| March | 8°C | −4°C | 2.1°C | 83 mm | 13 cm |
| April | 16°C | 1°C | 8.5°C | 89 mm | 2 cm |
| May | 21°C | 7°C | 14.1°C | 97 mm | 0 cm |
| June | 26°C | 12°C | 18.9°C | 110 mm | 0 cm |
| July | 28°C | 15°C | 21.1°C | 106 mm | 0 cm |
| August | 27°C | 14°C | 20.4°C | 102 mm | 0 cm |
| September | 24°C | 10°C | 16.6°C | 104 mm | 0 cm |
| October | 17°C | 4°C | 10.2°C | 84 mm | 0 cm |
| November | 10°C | −1°C | 4.3°C | 85 mm | 3 cm |
| December | 4°C | −5°C | −0.4°C | 86 mm | 17 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00361139; 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 Butler?
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 (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 USC00361139.
When is the last frost in Butler?
In Butler, the last spring frost (32°F) comes after May 7 in half of years and after May 23 in one year in ten; the first autumn frost comes before October 14 in half of years and before October 1 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 23; 9 in 10 after April 22
- First autumn frost, half of years before
- October 141 year in 10 before October 1; 9 in 10 before October 30
NOAA puts the median frost-free season at 159 days, and the season without a hard freeze (28°F) at 183 days.
A hard freeze (28°F) comes after April 26 in half of springs and before October 27 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Butler in zone 6b in ZIP code 16045, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Butler's NOAA station is in zone 6b: the coldest night of a typical year reaches −5°F (22 complete years).
Frost dates for every NOAA station in Pennsylvania · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00361139; 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 Butler?
In a normal year in Butler, 7 days a year reach 90°F, 140 nights fall to 32°F or colder and 168 days bring measurable precipitation.
- Days at 90°F or more
- 7a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 140a normal year
- Days that stay below freezing
- 36high of 32°F or less
- Days with 0.01 inch of precipitation
- 168a normal year
- Days with 1 inch of snow or more
- 13a normal year
The highest temperature in this station's record (since 1967) is 102°F, on July 17, 1988; the lowest is −20°F, on January 14, 1977.
The wettest calendar year on that record is 2004, with 55.73 in; the snowiest season is 2009–10, with 69.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00361139; records: ACIS (NOAA Regional Climate Centers), station USC00361139. Records use complete months only; a month missing more than three days is left out.
How sunny is Butler?
Over a year 68% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Butler, 3.7 kWh per square metre a day. August is the sunniest month (76%) and December the cloudiest (51%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 53% | 1.6 |
| February | 58% | 2.4 |
| March | 61% | 3.4 |
| April | 66% | 4.6 |
| May | 69% | 5.3 |
| June | 73% | 5.9 |
| July | 76% | 5.9 |
| August | 76% | 5.3 |
| September | 75% | 4.3 |
| October | 66% | 2.9 |
| November | 65% | 2.0 |
| December | 51% | 1.3 |
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 Butler need?
A normal year in Butler brings 6,457 heating degree days, 20% more than the median U.S. place (5,373), and 480 cooling degree days, 47% fewer 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 2,533 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,215 | 0 |
| February | 1,040 | 0 |
| March | 905 | 0 |
| April | 533 | 2 |
| May | 261 | 26 |
| June | 63 | 96 |
| July | 14 | 167 |
| August | 22 | 138 |
| September | 138 | 46 |
| October | 457 | 5 |
| November | 759 | 0 |
| December | 1,049 | 0 |
| Year (annual) | 6,457 | 480 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00361139. 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 Butler been warmer than normal lately?
Over 40 complete years from 1968 to 2019, the station's annual mean temperature rose at a fitted 3.8°F per century (+0.21°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Butler's climate compare?
Butler is warmer than 33 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 41. Across the 7,247 U.S. stations with normals, its annual mean of 48.5°F is warmer than 34%.
In the Köppen classification computed from these normals, Butler 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 Butler share this climate record?
21 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.
- Homeacre-Lyndora, PA6,647 people · 2 mi N
- Shanor-Northvue, PA5,183 people · 5 mi N
- Meridian, PA3,809 people · 2 mi W
- Meadowood, PA2,752 people · 1 mi E
- Oak Hills, PA2,567 people · 1 mi S
- Evans City, PA1,686 people · 9 mi SW
- Mars, PA1,415 people · 11 mi SW
- Saxonburg, PA1,378 people · 8 mi SE
- Nixon, PA1,214 people · 4 mi S
- Prospect, PA1,082 people · 8 mi NW
- Chicora, PA886 people · 12 mi NE
- Connoquenessing, PA786 people · 5 mi W
- East Butler, PA736 people · 4 mi NE
- Unionville, PA717 people · 7 mi N
- Valencia, PA684 people · 12 mi S
- Callery, PA346 people · 10 mi SW
- Fairview, PA187 people · 15 mi NE
- Petrolia, PA173 people · 16 mi NE
- Karns City, PA166 people · 15 mi NE
- Renfrew, PA128 people · 3 mi SW
- Fenelton, PA39 people · 10 mi E
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 Butler's climate
What is the coldest month in Butler?
January, with a normal high of 34°F and a normal low of 17°F. The warmest is July (82°F by day, 58°F at night).
Does it snow in Butler?
Yes: 35 inches in a normal year, falling on 33 days with 0.1 inch or more, the most in January (11.3 inches).
What is the rainiest month in Butler?
June, with 4.33 in of precipitation in a normal year; the driest is February with 2.66 in.
What plant hardiness zone is Butler in?
The USDA's 2023 map puts Butler in zone 6b in ZIP code 16045, the nearest ZIP area. By the same method at Butler's NOAA station, the coldest night of a typical year reaches −5°F (22 years, 1991-2020): zone 6b.
How late can frost come in Butler?
In half of years the last 32°F night comes after May 7; in one year in ten it comes after May 23. Waiting until May 23 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Butler in OctoberThis month day by day, its records and recent years
- Pennsylvania climateThe statewide normals and every place in the state
- Slippery Rock, PA17 miles from this station, 48.1°F a year
- Schenley, PA17 miles from this station, 51.8°F a year
- Natrona, PA19 miles from this station, 51.5°F a year
- Beaver Falls, PA22 miles from this station, 50.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made