January is one of the cooler months of the year in Harrisburg, with average highs near 1°C and lows around -7.1°C (mean -3°C). It is one of the drier months, averaging 73 mm of rainfall and 87% relative humidity across the period.
January is one of the cooler months of the year in Harrisburg. Across 45 years of records, the warmest January in Harrisburg was 2023 — when the month averaged 2.2°C — while the coldest was 1994 at -9.8°C. Typical January days reach 1°C with nights near -7.1°C. The long-term trend is warming, about 0.6°C per decade.
January is one of the drier months in Harrisburg, averaging 73 mm of rainfall. The wettest January on record was 1996 with 188 mm, while the driest was 1981 at 12 mm.
Relative humidity in Harrisburg during January averages 87%. The most humid January was 1994 at 97%, and the least humid was 2025 at 80%.
January receives about 1.8 kWh/m²/day of solar energy in Harrisburg. The sunniest Januarys were 2008, 2022 and 2025, among others at 2.1 kWh/m²/day, and the cloudiest were 2017, 2023 and 2024 at 1.5.
Average wind speed in Harrisburg during January is 0.9 m/s. The windiest Januarys were 1997, 2000 and 2004, among others at 1.1 m/s, while the calmest was 1984 at 0.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -4.9°C | -2.7°C | -2.7°C | -3.1°C | -1.4°C | +3.5°C |
| Avg High | -0.6°C | 1.4°C | 1.4°C | 1.0°C | 2.6°C | +3.2°C |
| Avg Low | -9.2°C | -6.9°C | -6.7°C | -7.1°C | -5.4°C | +3.8°C |
| Avg Rain | 54 mm | 102 mm | 69 mm | 70 mm | 69 mm | +15 mm |
January temperatures in Harrisburg have risen by about 4.1°C between 1981–1985 and 2021–2025.
January has ranged from a record low of -31°C (1994) to a record high of 18.5°C (1998).
Rainfall in January is one of the drier months, averaging 73 mm, with a wettest year of 188 mm.
A quieter season to visit Harrisburg
If your dates are flexible, the more temperate months of August and June tend to be the most comfortable for visiting Harrisburg. That said, January — with days averaging 1°C and nights around -7.1°C (mean -3°C) and moderate rainfall (73 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | -0.2°C | -4.1°C | -8.1°C | 6.8°C | -17.9°C | 23 mm | 80% | 1 m/s | 2.1 |
| 2024 | 3.2°C | -0.9°C | -4.9°C | 17.3°C | -12.9°C | 142 mm | 88% | 0.9 m/s | 1.5 |
| 2023 🔥 | 5.9°C | 2.2°C | -1.6°C | 13.6°C | -7.1°C | 74 mm | 89% | 0.8 m/s | 1.5 |
| 2022 | -0.1°C | -4.5°C | -8.9°C | 12.0°C | -16.7°C | 56 mm | 83% | 1 m/s | 2.1 |
| 2021 | 2.2°C | -1.2°C | -4.6°C | 7.0°C | -8.8°C | 44 mm | 86% | 0.9 m/s | 1.8 |
| 2020 | 4.6°C | 0.3°C | -4.0°C | 17.7°C | -12.1°C | 74 mm | 85% | 0.9 m/s | 1.8 |
| 2019 | 0.7°C | -3.5°C | -7.7°C | 10.5°C | -22.9°C | 94 mm | 88% | 1 m/s | 1.8 |
| 2018 | 1.0°C | -3.4°C | -7.8°C | 18.1°C | -17.8°C | 72 mm | 83% | 1 m/s | 1.9 |
| 2017 | 3.2°C | -0.1°C | -3.3°C | 12.5°C | -12.5°C | 75 mm | 84% | 0.9 m/s | 1.5 |
| 2016 | 1.0°C | -3.2°C | -7.3°C | 12.5°C | -16.3°C | 78 mm | 84% | 1 m/s | 2 |
| 2015 | -0.7°C | -4.7°C | -8.7°C | 5.2°C | -15.3°C | 54 mm | 83% | 1 m/s | 1.7 |
| 2014 | -1.2°C | -5.8°C | -10.3°C | 7.5°C | -19.8°C | 56 mm | 84% | 1 m/s | 1.9 |
| 2013 | 2.1°C | -1.9°C | -5.8°C | 16.8°C | -13.4°C | 80 mm | 88% | 0.9 m/s | 1.8 |
| 2012 | 3.3°C | -0.7°C | -4.7°C | 10.8°C | -13.3°C | 73 mm | 88% | 1 m/s | 2 |
| 2011 | -0.8°C | -4.7°C | -8.5°C | 5.1°C | -17.0°C | 43 mm | 87% | 0.8 m/s | 1.9 |
| 2010 | 0.9°C | -2.9°C | -6.8°C | 11.7°C | -14.8°C | 74 mm | 86% | 1 m/s | 1.8 |
| 2009 | -2.0°C | -6.0°C | -10.0°C | 5.5°C | -20.2°C | 55 mm | 88% | 0.9 m/s | 1.9 |
| 2008 | 3.0°C | -1.1°C | -5.2°C | 16.2°C | -13.8°C | 46 mm | 84% | 0.9 m/s | 2.1 |
| 2007 | 4.3°C | 0.4°C | -3.5°C | 16.8°C | -12.5°C | 69 mm | 85% | 0.9 m/s | 1.7 |
| 2006 | 5.7°C | 1.3°C | -3.2°C | 13.3°C | -9.7°C | 122 mm | 89% | 1 m/s | 1.7 |
| 2005 | 0.5°C | -3.7°C | -7.9°C | 16.4°C | -19.7°C | 123 mm | 91% | 0.9 m/s | 1.6 |
| 2004 | -2.6°C | -6.4°C | -10.3°C | 13.7°C | -17.7°C | 62 mm | 86% | 1.1 m/s | 1.9 |
| 2003 | -2.3°C | -5.8°C | -9.3°C | 6.5°C | -16.9°C | 53 mm | 86% | 1 m/s | 1.8 |
| 2002 | 5.1°C | 0.7°C | -3.7°C | 17.3°C | -11.8°C | 52 mm | 85% | 0.8 m/s | 1.9 |
| 2001 | 1.5°C | -2.7°C | -7.0°C | 5.7°C | -14.5°C | 50 mm | 89% | 0.8 m/s | 1.9 |
| 2000 | 0.7°C | -3.3°C | -7.2°C | 14.3°C | -16.6°C | 62 mm | 83% | 1.1 m/s | 2 |
| 1999 | 1.7°C | -2.9°C | -7.4°C | 16.6°C | -17.8°C | 152 mm | 87% | 0.9 m/s | 1.8 |
| 1998 | 4.7°C | 0.9°C | -2.9°C | 18.5°C | -12.8°C | 128 mm | 91% | 0.8 m/s | 1.6 |
| 1997 | 0.4°C | -3.6°C | -7.7°C | 15.2°C | -19.1°C | 57 mm | 86% | 1.1 m/s | 1.8 |
| 1996 🌧️ | -1.7°C | -6.1°C | -10.6°C | 9.6°C | -22.3°C | 188 mm | 93% | 1 m/s | 1.7 |
| 1995 | 2.8°C | -0.9°C | -4.6°C | 16.0°C | -13.0°C | 104 mm | 87% | 0.9 m/s | 2 |
| 1994 ❄️ | -5.0°C | -9.8°C | -14.6°C | 4.2°C | -31.0°C | 123 mm | 97% | 0.9 m/s | 1.9 |
| 1993 | 2.6°C | -1.0°C | -4.6°C | 12.6°C | -10.3°C | 56 mm | 85% | 0.9 m/s | 1.6 |
| 1992 | 2.8°C | -1.5°C | -5.7°C | 13.7°C | -12.6°C | 52 mm | 84% | 1 m/s | 1.8 |
| 1991 | 1.3°C | -2.8°C | -7.0°C | 8.0°C | -12.9°C | 64 mm | 87% | 0.9 m/s | 1.8 |
| 1990 | 4.1°C | 0.2°C | -3.8°C | 12.8°C | -8.6°C | 94 mm | 89% | 0.9 m/s | 1.7 |
| 1989 | 3.1°C | -1.4°C | -5.9°C | 9.1°C | -15.6°C | 55 mm | 86% | 0.9 m/s | 1.8 |
| 1988 | -1.0°C | -5.1°C | -9.2°C | 8.6°C | -16.4°C | 53 mm | 87% | 0.9 m/s | 1.9 |
| 1987 | -1.1°C | -5.2°C | -9.2°C | 8.5°C | -26.0°C | 88 mm | 95% | 0.9 m/s | 1.8 |
| 1986 | 1.1°C | -3.3°C | -7.8°C | 11.8°C | -17.4°C | 66 mm | 87% | 0.9 m/s | 1.9 |
| 1985 | -1.4°C | -5.2°C | -9.0°C | 12.5°C | -23.3°C | 27 mm | 83% | 1.1 m/s | 2.1 |
| 1984 | -3.1°C | -8.2°C | -13.2°C | 5.4°C | -27.0°C | 37 mm | 96% | 0.7 m/s | 1.7 |
| 1983 | 1.6°C | -2.3°C | -6.3°C | 7.3°C | -15.7°C | 53 mm | 86% | 0.9 m/s | — |
| 1982 | -3.3°C | -7.7°C | -12.0°C | 8.1°C | -21.2°C | 93 mm | 87% | 1 m/s | — |
| 1981 | -1.6°C | -5.8°C | -9.9°C | 8.2°C | -16.5°C | 12 mm | 82% | 0.9 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 1°C with lows near -7.1°C (mean -3°C), based on 45 years of NASA POWER data.
January averages 73 mm of rainfall in Harrisburg, one of the drier months. The wettest on record was 188 mm in 1996.
The hottest January reached 18.5°C in 1998. The coldest dipped to -31°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 4.1°C. Daytime highs moved from -1.6°C to 2.2°C and overnight lows from -10.1°C to -5.6°C over the same span.
January is one of the cooler months of the year in Harrisburg and one of the drier months, so plan for around 1°C daytime highs and -7.1°C at night.
Yes — January is the coldest month of the year in Harrisburg, averaging -3°C.
For January in Harrisburg, pack warm layers and a jacket for chilly mornings, with typical highs of 1°C and lows of -7.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in January averages 87% — quite humid.
Average wind speed in January is 0.9 m/s. The windiest January on record averaged 1.1 m/s (1985).
The wettest January on record was 1996 with 188 mm. On average, January sees 73 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Harrisburg behaves each January, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for January specifically, along with year-by-year records and how the month has changed over the decades.
