Harleysville Weather in December
Average highs run from 49°F on December 1 to 41°F on December 31, and lows from 28°F to 22°F. Normal precipitation for the month is 4.38 in over about 9 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 45°F
- Average low
- 25°F
- Precipitation
- 4.38 in
- Snowfall
- 2.2 in
- Record high
- 75°FDec 8, 1998
- Record low
- -3°FDec 14, 2005
- Chance of a freeze
- 100%
- Daylight
- 9 h 31 min to 9 h 21 min
- Cloud cover
- 67%
- Humidity
- 87%
- Dew point
- 28°F
- Wind
- 5.8 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Dec 1 | 49°F | 28°F | 67°F 2001 | 16°F 2013 | 29% | 2% |
| Dec 2 | 49°F | 28°F | 71°F 2006 | 13°F 2024 | 30% | 2% |
| Dec 3 | 49°F | 28°F | 65°F 2009 | 15°F 2000 | 30% | 2% |
| Dec 4 | 48°F | 28°F | 69°F 1998 | 10°F 2002 | 30% | 2% |
| Dec 5 | 48°F | 28°F | 72°F 1998 | 15°F 2006 | 30% | 2% |
| Dec 6 | 48°F | 27°F | 73°F 2001 | 15°F 2008 | 30% | 2% |
| Dec 7 | 47°F | 27°F | 70°F 2001 | 2°F 2002 | 30% | 2% |
| Dec 8 | 47°F | 27°F | 75°F 1998 | 5°F 2002 | 30% | 2% |
| Dec 9 | 47°F | 27°F | 56°F 2024 | 7°F 2025 | 30% | 2% |
| Dec 10 | 46°F | 26°F | 58°F 1999 | 7°F 2002 | 30% | 2% |
| Dec 11 | 46°F | 26°F | 61°F 2024 | 9°F 2005 | 30% | 2% |
| Dec 12 | 46°F | 26°F | 66°F 2021 | 10°F 2005 | 30% | 3% |
| Dec 13 | 45°F | 26°F | 62°F 2015 | 4°F 2005 | 30% | 3% |
| Dec 14 | 45°F | 26°F | 66°F 2015 | -3°F 2005 | 30% | 3% |
| Dec 15 | 45°F | 25°F | 67°F 2015 | 4°F 2005 | 30% | 3% |
| Dec 16 | 45°F | 25°F | 60°F 2008 | 6°F 2017 | 30% | 3% |
| Dec 17 | 44°F | 25°F | 63°F 2000 | 7°F 2017 | 30% | 3% |
| Dec 18 | 44°F | 25°F | 64°F 2000 | 12°F 2002 | 30% | 3% |
| Dec 19 | 44°F | 25°F | 65°F 2006 | 6°F 2020 | 30% | 3% |
| Dec 20 | 44°F | 24°F | 57°F 2017 | 5°F 2004 | 30% | 3% |
| Dec 21 | 43°F | 24°F | 61°F 2018 | 5°F 2004 | 30% | 3% |
| Dec 22 | 43°F | 24°F | 65°F 2013 | 5°F 2024 | 30% | 3% |
| Dec 23 | 43°F | 24°F | 66°F 2013 | 0°F 2024 | 29% | 3% |
| Dec 24 | 43°F | 24°F | 67°F 2015 | 0°F 2022 | 29% | 3% |
| Dec 25 | 42°F | 23°F | 69°F 2015 | 0°F 2022 | 29% | 3% |
| Dec 26 | 42°F | 23°F | 65°F 2015 | 6°F 2022 | 29% | 3% |
| Dec 27 | 42°F | 23°F | 53°F 2006 | 9°F 2017 | 29% | 3% |
| Dec 28 | 42°F | 23°F | 60°F 2015 | 3°F 2017 | 29% | 3% |
| Dec 29 | 42°F | 23°F | 63°F 2008 | 5°F 2017 | 29% | 3% |
| Dec 30 | 41°F | 22°F | 64°F 2024 | 6°F 2017 | 29% | 3% |
| Dec 31 | 41°F | 22°F | 61°F 2022 | 7°F 2017 | 29% | 3% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (EST).
- December 1
- sunrise 7:05 AM, sunset 4:36 PM
- December 31
- sunrise 7:24 AM, sunset 4:45 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00363437 (Graterford 1 E), public domain. Records: NOAA GHCN-Daily, station USC00367938, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.