Middletown, Pennsylvania climate: Normal weather by month, frost dates and records
Middletown's normal year runs from 23°F January nights to 87°F July afternoons, with 44.2 inches of precipitation and 30 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.4°C, January lows of −5°C, July highs of 30°C, 1,123 mm of precipitation a year.
- NOAA stationMiddletown Harrisburg Int'l Airport
- Station IDUSW00014711
- Location40.19°N 76.76°W
- Elevation312 ft (95 m)
- From the center2 miles
- Population9,748
On October 14, the normal high in Middletown is 66°F and the normal low 47°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 Middletown.
- Jan 39° 23°
- Feb 42° 25°
- Mar 51° 32°
- Apr 64° 43°
- May 74° 53°
- Jun 82° 63°
- Jul 87° 68°
- Aug 85° 66°
- Sep 78° 58°
- Oct 66° 46°
- Nov 54° 36°
- Dec 43° 28°
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 Middletown each month?
July is the warmest month, with normal highs of 87°F; January the coldest, with normal lows of 23°F. The most precipitation falls in September (4.83 in), the least in February (2.59 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 39°F | 23°F | 30.8°F | 3.03 | 9.1 | 11 | <1 | 26 | 9 h 40 min |
| February | 42°F | 25°F | 33.4°F | 2.59 | 9.4 | 10 | <1 | 23 | 10 h 40 min |
| March | 51°F | 32°F | 41.8°F | 3.70 | 5.6 | 11 | <1 | 16 | 11 h 50 min |
| April | 64°F | 43°F | 53.2°F | 3.55 | 0.4 | 11 | <1 | 3 | 13 h 10 min |
| May | 74°F | 53°F | 63.4°F | 3.83 | 0.0 | 13 | 1 | <1 | 14 h 20 min |
| June | 82°F | 63°F | 72.5°F | 3.98 | 0.0 | 12 | 4 | <1 | 15 h |
| July | 87°F | 68°F | 77.3°F | 4.74 | 0.0 | 11 | 9 | <1 | 14 h 50 min |
| August | 85°F | 66°F | 75.2°F | 3.77 | 0.0 | 10 | 6 | <1 | 13 h 50 min |
| September | 78°F | 58°F | 67.9°F | 4.83 | 0.0 | 9 | 2 | <1 | 12 h 30 min |
| October | 66°F | 46°F | 55.8°F | 3.81 | 0.2 | 9 | <1 | 1 | 11 h 10 min |
| November | 54°F | 36°F | 44.8°F | 2.97 | 0.8 | 9 | <1 | 11 | 10 h |
| December | 43°F | 28°F | 35.8°F | 3.43 | 4.4 | 10 | <1 | 22 | 9 h 20 min |
| Year (annual) | 64°F | 45°F | 54.3°F | 44.23 | 29.9 | 126 | 22 | 101 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 4°C | −5°C | −0.7°C | 77 mm | 23 cm |
| February | 6°C | −4°C | 0.8°C | 66 mm | 24 cm |
| March | 11°C | 0°C | 5.4°C | 94 mm | 14 cm |
| April | 18°C | 6°C | 11.8°C | 90 mm | 1 cm |
| May | 23°C | 12°C | 17.4°C | 97 mm | 0 cm |
| June | 28°C | 17°C | 22.5°C | 101 mm | 0 cm |
| July | 30°C | 20°C | 25.2°C | 120 mm | 0 cm |
| August | 29°C | 19°C | 24.0°C | 96 mm | 0 cm |
| September | 25°C | 15°C | 19.9°C | 123 mm | 0 cm |
| October | 19°C | 8°C | 13.2°C | 97 mm | 1 cm |
| November | 12°C | 2°C | 7.1°C | 75 mm | 2 cm |
| December | 6°C | −2°C | 2.1°C | 87 mm | 11 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014711; 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 Middletown?
Normal highs sit between 65°F and 85°F in May, June, August, September and October. 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 USW00014711.
When is the last frost in Middletown?
In Middletown, the last spring frost (32°F) comes after April 9 in half of years and after April 25 in one year in ten; the first autumn frost comes before November 2 in half of years and before October 18 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 91 year in 10 after April 25; 9 in 10 after March 28
- First autumn frost, half of years before
- November 21 year in 10 before October 18; 9 in 10 before November 15
NOAA puts the median frost-free season at 206 days, and the season without a hard freeze (28°F) at 230 days.
A hard freeze (28°F) comes after March 30 in half of springs and before November 14 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Middletown in zone 7a in ZIP code 17057, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Middletown's NOAA station is in zone 7a: the coldest night of a typical year reaches 5°F (29 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 USW00014711; 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 Middletown?
In a normal year in Middletown, 22 days a year reach 90°F (1 of them 100°F or more), 101 nights fall to 32°F or colder and 126 days bring measurable precipitation.
- Days at 90°F or more
- 22a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 101a normal year
- Days that stay below freezing
- 19high of 32°F or less
- Days with 0.01 inch of precipitation
- 126a normal year
- Days with 1 inch of snow or more
- 8a normal year
The highest temperature in this station's record (since 1941) is 103°F, on July 22, 2011; the lowest is −22°F, on January 21, 1994.
The wettest calendar year on that record is 2011, with 73.73 in; the snowiest season is 1995–96, with 77.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00014711; records: ACIS (NOAA Regional Climate Centers), station USW00014711. Records use complete months only; a month missing more than three days is left out.
How sunny is Middletown?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Middletown, 3.9 kWh per square metre a day. July is the sunniest month (79%) and December the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 63% | 1.8 |
| February | 66% | 2.7 |
| March | 66% | 3.6 |
| April | 69% | 4.8 |
| May | 69% | 5.3 |
| June | 75% | 6.0 |
| July | 79% | 6.0 |
| August | 76% | 5.2 |
| September | 74% | 4.2 |
| October | 68% | 2.9 |
| November | 69% | 2.1 |
| December | 60% | 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 Middletown need?
A normal year in Middletown brings 5,024 heating degree days, 6% fewer than the median U.S. place (5,373), and 1,171 cooling degree days, 29% 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 3,702 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,060 | 0 |
| February | 886 | 0 |
| March | 720 | 1 |
| April | 365 | 9 |
| May | 121 | 72 |
| June | 12 | 239 |
| July | 0 | 381 |
| August | 1 | 319 |
| September | 48 | 135 |
| October | 300 | 16 |
| November | 605 | 0 |
| December | 907 | 0 |
| Year (annual) | 5,024 | 1,171 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014711. 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 Middletown been warmer than normal lately?
2025 averaged 54.3°F, equal to the 1991-2020 normal of 54.3°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 56.7°F | +2.4°F | 46.28 | 25.4 |
| 2022 | 55.0°F | +0.7°F | 42.26 | 17.3 |
| 2023 | 56.7°F | +2.4°F | 37.52 | 3.9 |
| 2024 | 56.7°F | +2.4°F | 42.97 | 20.5 |
| 2025 | 54.3°F | at normal | 39.69 | 18.6 |
Over 34 complete years from 1992 to 2025, the station's annual mean temperature rose at a fitted 7.5°F per century (+0.41°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00014711; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Middletown's climate compare?
Middletown is warmer than 102 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 56. Across the 7,247 U.S. stations with normals, its annual mean of 54.3°F is warmer than 58%.
In the Köppen classification computed from these normals, Middletown 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 Middletown share this climate record?
15 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.
- Hershey, PA14,334 people · 9 mi NE
- Elizabethtown, PA11,993 people · 9 mi E
- Rutherford, PA6,982 people · 5 mi N
- Hummelstown, PA4,542 people · 6 mi NE
- Valley Green, PA3,121 people · 3 mi SW
- Manchester, PA2,823 people · 9 mi S
- Highspire, PA2,734 people · 2 mi NW
- Mount Wolf, PA1,439 people · 10 mi S
- Bainbridge, PA1,357 people · 9 mi SE
- Royalton, PA1,134 people · 2 mi E
- Goldsboro, PA936 people · 3 mi S
- Union Deposit, PA751 people · 8 mi NE
- York Haven, PA695 people · 6 mi SE
- Saginaw, PA584 people · 10 mi SE
- Falmouth, PA508 people · 5 mi SE
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 Middletown's climate
What is the coldest month in Middletown?
January, with a normal high of 39°F and a normal low of 23°F. The warmest is July (87°F by day, 68°F at night).
Does it snow in Middletown?
Yes: 30 inches in a normal year, falling on 16 days with 0.1 inch or more, the most in February (9.4 inches).
What is the rainiest month in Middletown?
September, with 4.83 in of precipitation in a normal year; the driest is February with 2.59 in.
What plant hardiness zone is Middletown in?
The USDA's 2023 map puts Middletown in zone 7a in ZIP code 17057, the nearest ZIP area. By the same method at Middletown's NOAA station, the coldest night of a typical year reaches 5°F (29 years, 1991-2020): zone 7a.
How late can frost come in Middletown?
In half of years the last 32°F night comes after April 9; in one year in ten it comes after April 25. Waiting until April 25 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Pennsylvania climateThe statewide normals and every place in the state
- Harrisburg, PA5 miles from this station, 55.2°F a year
- Lebanon, PA19 miles from this station, 52.3°F a year
- Dehart Dam, PA19 miles from this station, 50.6°F a year
- Landisville, PA19 miles from this station, 51.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made