August is one of the warmer months of the year in Harrisburg, with average highs near 29.1°C and lows around 16.8°C (mean 23°C). It is about average for rainfall, averaging 100 mm of rainfall and 68% relative humidity across the period.
August is one of the warmer months of the year in Harrisburg. Across 45 years of records, the warmest August in Harrisburg was 2016 — when the month averaged 25.4°C — while the coldest was 1994 at 20.3°C. Typical August days reach 29.1°C with nights near 16.8°C. The long-term trend is warming, about 0.3°C per decade.
August is about average for rainfall in Harrisburg, averaging 100 mm of rainfall. The wettest August on record was 2011 with 202 mm, while the driest was 1995 at 29 mm.
Relative humidity in Harrisburg during August averages 68%. The most humid August was 2018 at 85%, and the least humid were 1995 and 2002 at 55%.
August receives about 5.2 kWh/m²/day of solar energy in Harrisburg. The sunniest August was 2015 at 5.8 kWh/m²/day, and the cloudiest was 1990 at 4.7.
Average wind speed in Harrisburg during August is 0.4 m/s. The windiest August was 2023 at 0.5 m/s, while the calmest were 2022, 2024 and 2025, among others at 0.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.3°C | 22.5°C | 23.3°C | 23.0°C | 23.8°C | +1.5°C |
| Avg High | 28.7°C | 28.9°C | 29.2°C | 28.9°C | 29.9°C | +1.2°C |
| Avg Low | 15.9°C | 16.1°C | 17.3°C | 17.1°C | 17.7°C | +1.8°C |
| Avg Rain | 84 mm | 102 mm | 99 mm | 108 mm | 111 mm | +27 mm |
August temperatures in Harrisburg have risen by about 1.6°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 4.6°C (1982) to a record high of 38.4°C (2002).
Rainfall in August is about average for rainfall, averaging 100 mm, with a wettest year of 202 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.2°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.
One of the best times to visit Harrisburg
August is one of the best times to visit Harrisburg. Expect days averaging 29.1°C and nights around 16.8°C (mean 23°C) — warmer than Harrisburg's yearly average — with higher rainfall (100 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 29.5°C | 22.6°C | 15.8°C | 35.8°C | 8.5°C | 39 mm | 59% | 0.4 m/s | 5.4 |
| 2024 | 28.5°C | 22.8°C | 17.0°C | 35.0°C | 9.8°C | 165 mm | 75% | 0.4 m/s | 5 |
| 2023 | 28.8°C | 23.0°C | 17.1°C | 32.6°C | 12.4°C | 109 mm | 69% | 0.5 m/s | 5.2 |
| 2022 | 31.7°C | 25.1°C | 18.5°C | 36.9°C | 12.9°C | 84 mm | 62% | 0.4 m/s | 5.7 |
| 2021 | 30.5°C | 24.9°C | 19.4°C | 36.5°C | 14.0°C | 152 mm | 73% | 0.4 m/s | 4.9 |
| 2020 | 30.6°C | 24.6°C | 18.6°C | 34.5°C | 13.5°C | 115 mm | 68% | 0.4 m/s | 5.3 |
| 2019 | 29.4°C | 23.5°C | 17.6°C | 33.7°C | 12.4°C | 84 mm | 71% | 0.4 m/s | 5.4 |
| 2018 | 27.5°C | 23.0°C | 18.6°C | 33.3°C | 13.0°C | 175 mm | 85% | 0.4 m/s | 5 |
| 2017 | 26.8°C | 21.3°C | 15.7°C | 32.1°C | 10.9°C | 113 mm | 75% | 0.4 m/s | 5.2 |
| 2016 🔥 | 31.7°C | 25.4°C | 19.2°C | 35.4°C | 12.7°C | 82 mm | 67% | 0.4 m/s | 5.6 |
| 2015 | 30.1°C | 23.3°C | 16.6°C | 35.4°C | 12.3°C | 71 mm | 61% | 0.4 m/s | 5.8 |
| 2014 | 27.6°C | 21.3°C | 15.1°C | 33.4°C | 10.0°C | 96 mm | 71% | 0.4 m/s | 5.2 |
| 2013 | 28.6°C | 22.4°C | 16.3°C | 33.1°C | 9.7°C | 85 mm | 69% | 0.4 m/s | 5 |
| 2012 | 29.4°C | 23.4°C | 17.4°C | 33.7°C | 12.1°C | 95 mm | 67% | 0.4 m/s | 5.4 |
| 2011 🌧️ | 27.8°C | 22.3°C | 16.8°C | 32.6°C | 9.9°C | 202 mm | 74% | 0.4 m/s | 4.9 |
| 2010 | 30.3°C | 24.0°C | 17.7°C | 35.3°C | 11.4°C | 78 mm | 65% | 0.4 m/s | 4.9 |
| 2009 | 27.9°C | 22.8°C | 17.7°C | 33.2°C | 11.4°C | 143 mm | 78% | 0.4 m/s | 5.2 |
| 2008 | 28.1°C | 21.6°C | 15.1°C | 31.7°C | 10.3°C | 56 mm | 65% | 0.4 m/s | 5.7 |
| 2007 | 29.7°C | 23.7°C | 17.6°C | 35.5°C | 13.0°C | 132 mm | 68% | 0.4 m/s | 5.1 |
| 2006 | 29.7°C | 23.5°C | 17.3°C | 36.0°C | 11.2°C | 84 mm | 66% | 0.4 m/s | 5.5 |
| 2005 | 31.0°C | 24.9°C | 18.7°C | 37.6°C | 12.8°C | 71 mm | 65% | 0.4 m/s | 4.9 |
| 2004 | 26.5°C | 21.2°C | 16.0°C | 31.3°C | 10.6°C | 133 mm | 80% | 0.4 m/s | 5 |
| 2003 | 28.0°C | 23.0°C | 18.0°C | 31.7°C | 10.3°C | 148 mm | 81% | 0.4 m/s | 4.9 |
| 2002 | 31.9°C | 25.1°C | 18.3°C | 38.4°C | 12.6°C | 51 mm | 55% | 0.4 m/s | 5.4 |
| 2001 | 31.6°C | 24.9°C | 18.3°C | 37.9°C | 14.2°C | 91 mm | 62% | 0.4 m/s | 5.1 |
| 2000 | 27.8°C | 22.1°C | 16.3°C | 32.7°C | 8.4°C | 77 mm | 69% | 0.4 m/s | 4.8 |
| 1999 | 29.4°C | 22.8°C | 16.2°C | 35.4°C | 10.3°C | 117 mm | 61% | 0.4 m/s | 5.3 |
| 1998 | 29.9°C | 23.3°C | 16.7°C | 32.7°C | 8.8°C | 78 mm | 65% | 0.4 m/s | 5.3 |
| 1997 | 27.4°C | 21.2°C | 15.1°C | 33.9°C | 10.3°C | 121 mm | 67% | 0.4 m/s | 5.2 |
| 1996 | 27.5°C | 21.7°C | 15.9°C | 31.8°C | 11.6°C | 71 mm | 75% | 0.4 m/s | 5.5 |
| 1995 | 32.7°C | 25.3°C | 17.9°C | 37.1°C | 12.4°C | 29 mm | 55% | 0.4 m/s | 5.5 |
| 1994 ❄️ | 26.0°C | 20.3°C | 14.6°C | 31.9°C | 7.9°C | 168 mm | 78% | 0.4 m/s | 4.8 |
| 1993 | 30.2°C | 23.6°C | 17.0°C | 35.9°C | 9.8°C | 95 mm | 65% | 0.4 m/s | 5.2 |
| 1992 | 27.5°C | 21.0°C | 14.5°C | 33.5°C | 9.2°C | 65 mm | 67% | 0.4 m/s | 5.4 |
| 1991 | 30.6°C | 23.9°C | 17.1°C | 36.2°C | 13.1°C | 106 mm | 62% | 0.4 m/s | 5.4 |
| 1990 | 27.7°C | 21.8°C | 16.0°C | 32.7°C | 11.9°C | 171 mm | 75% | 0.4 m/s | 4.7 |
| 1989 | 27.5°C | 21.8°C | 16.2°C | 31.0°C | 9.8°C | 58 mm | 74% | 0.4 m/s | 4.9 |
| 1988 | 31.1°C | 24.4°C | 17.7°C | 37.9°C | 9.1°C | 95 mm | 61% | 0.4 m/s | 5.2 |
| 1987 | 29.8°C | 23.0°C | 16.2°C | 35.9°C | 9.1°C | 99 mm | 62% | 0.4 m/s | 4.9 |
| 1986 | 26.9°C | 21.0°C | 15.0°C | 30.7°C | 6.3°C | 114 mm | 70% | 0.4 m/s | 5.4 |
| 1985 | 28.1°C | 22.1°C | 16.0°C | 34.5°C | 11.2°C | 68 mm | 66% | 0.4 m/s | 5.1 |
| 1984 | 27.2°C | 21.7°C | 16.2°C | 30.2°C | 7.3°C | 108 mm | 80% | 0.4 m/s | 5.6 |
| 1983 | 31.1°C | 24.1°C | 17.1°C | 36.6°C | 9.6°C | 78 mm | 63% | 0.4 m/s | — |
| 1982 | 27.5°C | 20.7°C | 13.8°C | 32.8°C | 4.6°C | 74 mm | 64% | 0.4 m/s | — |
| 1981 | 29.2°C | 22.1°C | 15.0°C | 32.4°C | 8.5°C | 59 mm | 62% | 0.4 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 29.1°C with lows near 16.8°C (mean 23°C), based on 45 years of NASA POWER data.
August averages 100 mm of rainfall in Harrisburg, about average for rainfall. The wettest on record was 202 mm in 2011.
The hottest August reached 38.4°C in 2002. The coldest dipped to 4.6°C in 1982.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.6°C. Daytime highs moved from 28.6°C to 29.8°C and overnight lows from 15.6°C to 17.6°C over the same span.
August is one of the warmer months of the year in Harrisburg and about average for rainfall, so plan for around 29.1°C daytime highs and 16.8°C at night.
Not quite — August is the 11th coolest month in Harrisburg, averaging 23°C.
For August in Harrisburg, pack light layers you can adjust through the day, with typical highs of 29.1°C and lows of 16.8°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 68% — moderately humid.
Average wind speed in August is 0.4 m/s. The windiest August on record averaged 0.5 m/s (2023).
The wettest August on record was 2011 with 202 mm. On average, August sees 100 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 August, 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 August specifically, along with year-by-year records and how the month has changed over the decades.
