Chambersburg, Pennsylvania climate: Normal weather by month, frost dates and records
Chambersburg's normal year runs from 23°F January nights to 85°F July afternoons, with 43.5 inches of precipitation and 31 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 11.6°C, January lows of −5°C, July highs of 29°C, 1,106 mm of precipitation a year.
- NOAA stationChambersburg (1 mi ESE)
- Station IDUSC00361354
- Location39.94°N 77.64°W
- Elevation640 ft (195 m)
- Population23,041
On October 22, the normal high in Chambersburg is 62°F and the normal low 42°F, and the chance of measurable rain or snow is 29%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Chambersburg.
- Jan 37° 23°
- Feb 41° 25°
- Mar 50° 32°
- Apr 63° 42°
- May 73° 52°
- Jun 81° 61°
- Jul 85° 65°
- Aug 83° 63°
- Sep 76° 56°
- Oct 64° 45°
- Nov 52° 35°
- Dec 41° 27°
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 Chambersburg each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 23°F. The most precipitation falls in September (4.14 in), the least in February (2.61 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 | 37°F | 23°F | 30.2°F | 3.21 | 10.0 | 10 | <1 | 26 | 9 h 40 min |
| February | 41°F | 25°F | 32.7°F | 2.61 | 8.0 | 9 | <1 | 23 | 10 h 40 min |
| March | 50°F | 32°F | 41.1°F | 3.61 | 6.0 | 10 | <1 | 17 | 11 h 50 min |
| April | 63°F | 42°F | 52.4°F | 3.98 | 0.3 | 11 | <1 | 5 | 13 h 10 min |
| May | 73°F | 52°F | 62.1°F | 4.13 | 0.0 | 12 | 1 | <1 | 14 h 20 min |
| June | 81°F | 61°F | 70.7°F | 4.10 | 0.0 | 11 | 4 | <1 | 15 h |
| July | 85°F | 65°F | 74.8°F | 3.83 | 0.0 | 10 | 8 | <1 | 14 h 50 min |
| August | 83°F | 63°F | 72.9°F | 3.82 | 0.0 | 9 | 5 | <1 | 13 h 50 min |
| September | 76°F | 56°F | 65.7°F | 4.14 | 0.0 | 9 | 1 | <1 | 12 h 30 min |
| October | 64°F | 45°F | 54.3°F | 3.53 | 0.0 | 9 | <1 | 2 | 11 h 10 min |
| November | 52°F | 35°F | 43.5°F | 3.12 | 1.0 | 8 | <1 | 12 | 10 h |
| December | 41°F | 27°F | 34.4°F | 3.45 | 5.5 | 9 | <1 | 23 | 9 h 20 min |
| Year (annual) | 62°F | 44°F | 52.9°F | 43.53 | 30.8 | 117 | 19 | 109 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 3°C | −5°C | −1.0°C | 82 mm | 25 cm |
| February | 5°C | −4°C | 0.4°C | 66 mm | 20 cm |
| March | 10°C | 0°C | 5.1°C | 92 mm | 15 cm |
| April | 17°C | 5°C | 11.3°C | 101 mm | 1 cm |
| May | 23°C | 11°C | 16.7°C | 105 mm | 0 cm |
| June | 27°C | 16°C | 21.5°C | 104 mm | 0 cm |
| July | 29°C | 18°C | 23.8°C | 97 mm | 0 cm |
| August | 28°C | 17°C | 22.7°C | 97 mm | 0 cm |
| September | 24°C | 13°C | 18.7°C | 105 mm | 0 cm |
| October | 18°C | 7°C | 12.4°C | 90 mm | 0 cm |
| November | 11°C | 2°C | 6.4°C | 79 mm | 3 cm |
| December | 5°C | −3°C | 1.3°C | 88 mm | 14 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00361354; 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 Chambersburg?
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 (9).
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 USC00361354.
When is the last frost in Chambersburg?
In Chambersburg, the last spring frost (32°F) comes after April 18 in half of years and after May 5 in one year in ten; the first autumn frost comes before October 25 in half of years and before October 10 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 181 year in 10 after May 5; 9 in 10 after April 3
- First autumn frost, half of years before
- October 251 year in 10 before October 10; 9 in 10 before November 8
NOAA puts the median frost-free season at 188 days, and the season without a hard freeze (28°F) at 213 days.
A hard freeze (28°F) comes after April 4 in half of springs and before November 6 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Chambersburg in zone 7a in ZIP code 17201. By the map's own method, the average of each year's coldest night over 1991-2020, Chambersburg's NOAA station is in zone 7a: the coldest night of a typical year reaches 3°F (26 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 USC00361354; 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 Chambersburg?
In a normal year in Chambersburg, 19 days a year reach 90°F, 109 nights fall to 32°F or colder and 117 days bring measurable precipitation.
- Days at 90°F or more
- 19a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 109a normal year
- Days that stay below freezing
- 21high of 32°F or less
- Days with 0.01 inch of precipitation
- 117a normal year
- Days with 1 inch of snow or more
- 8a normal year
The highest temperature in this station's record (since 1894) is 107°F, on July 10, 1936; the lowest is −21°F, on January 21, 1994.
The wettest calendar year on that record is 1996, with 62.11 in; the snowiest season is 1960–61, with 72.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00361354; records: ACIS (NOAA Regional Climate Centers), station USC00361354. Records use complete months only; a month missing more than three days is left out.
How sunny is Chambersburg?
Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Chambersburg, 4.0 kWh per square metre a day. July is the sunniest month (79%) and January the cloudiest (65%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 65% | 2.0 |
| February | 68% | 2.8 |
| March | 68% | 3.8 |
| April | 71% | 4.9 |
| May | 71% | 5.4 |
| June | 77% | 6.1 |
| July | 79% | 6.0 |
| August | 78% | 5.3 |
| September | 75% | 4.3 |
| October | 72% | 3.1 |
| November | 72% | 2.3 |
| December | 66% | 1.7 |
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 Chambersburg need?
A normal year in Chambersburg brings 5,302 heating degree days, 1% fewer than the median U.S. place (5,373), and 926 cooling degree days, 2% 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 3,351 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,080 | 0 |
| February | 903 | 0 |
| March | 740 | 1 |
| April | 387 | 9 |
| May | 150 | 58 |
| June | 21 | 192 |
| July | 1 | 305 |
| August | 5 | 251 |
| September | 78 | 97 |
| October | 344 | 12 |
| November | 645 | 0 |
| December | 949 | 0 |
| Year (annual) | 5,302 | 926 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00361354. 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 Chambersburg been warmer than normal lately?
2024 averaged 56.4°F, 3.5°F above the 1991-2020 normal of 52.9°F. 2 of the 2 complete years since 2023 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2023 | 55.9°F | +3.0°F | 32.05 | 4.3 |
| 2024 | 56.4°F | +3.5°F | 34.43 | 22.5 |
Over 80 complete years from 1877 to 2024, the station's annual mean temperature rose at a fitted 1.5°F per century (+0.08°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00361354; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Chambersburg's climate compare?
Chambersburg is warmer than 93 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 46. Across the 7,247 U.S. stations with normals, its annual mean of 52.9°F is warmer than 53%.
In the Köppen classification computed from these normals, Chambersburg 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 Chambersburg share this climate record?
4 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.
- Guilford, PA3,673 people · 2 mi SE
- Fayetteville, PA2,431 people · 4 mi SE
- Scotland, PA1,535 people · 4 mi NE
- Burnt Cabins, PA9 people · 17 mi NW
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 Chambersburg's climate
What is the coldest month in Chambersburg?
January, with a normal high of 37°F and a normal low of 23°F. The warmest is July (85°F by day, 65°F at night).
Does it snow in Chambersburg?
Yes: 31 inches in a normal year, falling on 13 days with 0.1 inch or more, the most in January (10.0 inches).
What is the rainiest month in Chambersburg?
September, with 4.14 in of precipitation in a normal year; the driest is February with 2.61 in.
What plant hardiness zone is Chambersburg in?
The USDA's 2023 map puts Chambersburg in zone 7a in ZIP code 17201. By the same method at Chambersburg's NOAA station, the coldest night of a typical year reaches 3°F (26 years, 1991-2020): zone 7a.
How late can frost come in Chambersburg?
In half of years the last 32°F night comes after April 18; in one year in ten it comes after May 5. Waiting until May 5 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Chambersburg in OctoberThis month day by day, its records and recent years
- Pennsylvania climateThe statewide normals and every place in the state
- South Mountain, PA9 miles from this station, 50.0°F a year
- Shippensburg, PA11 miles from this station, 53.2°F a year
- Cashtown, PA16 miles from this station, 51.3°F a year
- Hagerstown, MD16 miles from this station, 55.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made