Sunbury, Pennsylvania climate: Normal weather by month, frost dates and records
Sunbury's normal year runs from 19°F January nights to 84°F July afternoons, with 43.7 inches of precipitation and 29 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.2°C, January lows of −7°C, July highs of 29°C, 1,110 mm of precipitation a year.
- NOAA stationSunbury
- Station IDUSC00368668
- Location40.85°N 76.79°W
- Elevation575 ft (175 m)
- Population9,549
On October 24, the normal high in Sunbury is 60°F and the normal low 38°F, and the chance of measurable rain or snow is 33%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Sunbury.
- Jan 35° 19°
- Feb 39° 21°
- Mar 48° 27°
- Apr 61° 37°
- May 72° 47°
- Jun 80° 57°
- Jul 84° 60°
- Aug 82° 59°
- Sep 75° 51°
- Oct 64° 40°
- Nov 51° 32°
- 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 Sunbury each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 19°F. The most precipitation falls in September (4.52 in), the least in February (2.30 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 35°F | 19°F | 27.1°F | 2.98 | 7.6 | 10 | <1 | 28 | 9 h 30 min |
| February | 39°F | 21°F | 29.8°F | 2.30 | 8.6 | 9 | <1 | 26 | 10 h 40 min |
| March | 48°F | 27°F | 37.6°F | 3.33 | 5.2 | 10 | <1 | 22 | 11 h 50 min |
| April | 61°F | 37°F | 49.2°F | 3.74 | 0.6 | 12 | <1 | 9 | 13 h 20 min |
| May | 72°F | 47°F | 59.5°F | 3.77 | 0.0 | 14 | 1 | 1 | 14 h 30 min |
| June | 80°F | 57°F | 68.3°F | 4.38 | 0.0 | 12 | 3 | <1 | 15 h 10 min |
| July | 84°F | 60°F | 72.4°F | 4.32 | 0.0 | 11 | 8 | <1 | 14 h 50 min |
| August | 82°F | 59°F | 70.7°F | 3.93 | 0.0 | 11 | 3 | <1 | 13 h 50 min |
| September | 75°F | 51°F | 63.1°F | 4.52 | 0.0 | 9 | 2 | <1 | 12 h 30 min |
| October | 64°F | 40°F | 52.0°F | 3.92 | 0.2 | 11 | <1 | 5 | 11 h 10 min |
| November | 51°F | 32°F | 41.3°F | 3.16 | 1.5 | 9 | <1 | 19 | 10 h |
| December | 40°F | 25°F | 32.3°F | 3.34 | 4.9 | 10 | <1 | 25 | 9 h 20 min |
| Year (annual) | 61°F | 40°F | 50.3°F | 43.69 | 28.6 | 127 | 16 | 134 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 2°C | −7°C | −2.7°C | 76 mm | 19 cm |
| February | 4°C | −6°C | −1.2°C | 58 mm | 22 cm |
| March | 9°C | −3°C | 3.1°C | 85 mm | 13 cm |
| April | 16°C | 3°C | 9.6°C | 95 mm | 2 cm |
| May | 22°C | 8°C | 15.3°C | 96 mm | 0 cm |
| June | 27°C | 14°C | 20.2°C | 111 mm | 0 cm |
| July | 29°C | 16°C | 22.4°C | 110 mm | 0 cm |
| August | 28°C | 15°C | 21.5°C | 100 mm | 0 cm |
| September | 24°C | 11°C | 17.3°C | 115 mm | 0 cm |
| October | 18°C | 5°C | 11.1°C | 100 mm | 1 cm |
| November | 10°C | 0°C | 5.2°C | 80 mm | 4 cm |
| December | 5°C | −4°C | 0.2°C | 85 mm | 12 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00368668; 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 Sunbury?
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 USC00368668.
When is the last frost in Sunbury?
In Sunbury, the last spring frost (32°F) comes after April 30 in half of years and after May 19 in one year in ten; the first autumn frost comes before October 13 in half of years and before September 30 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 301 year in 10 after May 19; 9 in 10 after April 15
- First autumn frost, half of years before
- October 131 year in 10 before September 30; 9 in 10 before October 31
NOAA puts the median frost-free season at 166 days, and the season without a hard freeze (28°F) at 193 days.
A hard freeze (28°F) comes after April 14 in half of springs and before October 26 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Sunbury in zone 6b in ZIP code 17876, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Sunbury's NOAA station is in zone 6b: the coldest night of a typical year reaches −1°F (19 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 USC00368668; 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 Sunbury?
In a normal year in Sunbury, 16 days a year reach 90°F, 134 nights fall to 32°F or colder and 127 days bring measurable precipitation.
- Days at 90°F or more
- 16a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 134a normal year
- Days that stay below freezing
- 28high of 32°F or less
- Days with 0.01 inch of precipitation
- 127a normal year
- Days with 1 inch of snow or more
- 9a normal year
The highest temperature in this station's record (since 1957) is 102°F, on July 4, 1966; the lowest is −15°F, on January 22, 1961.
The wettest calendar year on that record is 2011, with 74.13 in; the snowiest season is 1935–36, with 66.4 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00368668; records: ACIS (NOAA Regional Climate Centers), station USC00368668. Records use complete months only; a month missing more than three days is left out.
How sunny is Sunbury?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Sunbury, 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 Sunbury need?
A normal year in Sunbury brings 6,006 heating degree days, 12% more than the median U.S. place (5,373), and 669 cooling degree days, 26% 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 2,859 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,175 | 0 |
| February | 986 | 0 |
| March | 851 | 0 |
| April | 480 | 5 |
| May | 206 | 33 |
| June | 38 | 137 |
| July | 8 | 236 |
| August | 12 | 188 |
| September | 120 | 64 |
| October | 410 | 7 |
| November | 711 | 0 |
| December | 1,012 | 0 |
| Year (annual) | 6,006 | 669 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00368668. 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 Sunbury been warmer than normal lately?
2025 averaged 50.8°F, 0.5°F above the 1991-2020 normal of 50.3°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 52.6°F | +2.3°F | 46.91 | – |
| 2022 | 51.0°F | +0.7°F | 41.52 | 27.3 |
| 2023 | 52.3°F | +2.0°F | 49.54 | 8.1 |
| 2024 | 52.6°F | +2.3°F | 43.66 | 24.6 |
| 2025 | 50.8°F | +0.5°F | 37.26 | 14.5 |
Source: observed years: ACIS, station USC00368668. A year counts only with all twelve months complete.
How does Sunbury's climate compare?
Sunbury is warmer than 48 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 48. Across the 7,247 U.S. stations with normals, its annual mean of 50.3°F is warmer than 42%.
In the Köppen classification computed from these normals, Sunbury 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 Sunbury share this climate record?
6 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.
- Northumberland, PA3,835 people · 3 mi N
- Riverside, PA2,004 people · 10 mi NE
- Trevorton, PA1,809 people · 8 mi SE
- Shamokin Dam, PA1,633 people · 2 mi W
- Kapp Heights, PA772 people · 3 mi N
- Snydertown, PA316 people · 6 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 Sunbury's climate
What is the coldest month in Sunbury?
January, with a normal high of 35°F and a normal low of 19°F. The warmest is July (84°F by day, 60°F at night).
Does it snow in Sunbury?
Yes: 29 inches in a normal year, falling on 14 days with 0.1 inch or more, the most in February (8.6 inches).
What is the rainiest month in Sunbury?
September, with 4.52 in of precipitation in a normal year; the driest is February with 2.30 in.
What plant hardiness zone is Sunbury in?
The USDA's 2023 map puts Sunbury in zone 6b in ZIP code 17876, the nearest ZIP area. By the same method at Sunbury's NOAA station, the coldest night of a typical year reaches −1°F (19 years, 1991-2020): zone 6b.
How late can frost come in Sunbury?
In half of years the last 32°F night comes after April 30; in one year in ten it comes after May 19. Waiting until May 19 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Pennsylvania climateThe statewide normals and every place in the state
- Selinsgrove, PA4 miles from this station, 51.1°F a year
- Lewisburg, PA8 miles from this station, 50.4°F a year
- Bear Gap, PA16 miles from this station, 50.5°F a year
- Laurelton, PA22 miles from this station, 51.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made