August is one of the warmer months of the year in Hartford, with average highs near 27.8°C and lows around 15.9°C (mean 21.9°C). It is about average for rainfall, averaging 103 mm of rainfall and 73% relative humidity across the period.
August is one of the warmer months of the year in Hartford. Across 45 years of records, the warmest August in Hartford was 2022 — when the month averaged 24.9°C — while the coldest was 1982 at 19.4°C. Typical August days reach 27.8°C with nights near 15.9°C. The long-term trend is warming, about 0.4°C per decade.
August is about average for rainfall in Hartford, averaging 103 mm of rainfall. The wettest August on record was 2011 with 294 mm, while the driest was 1984 at 36 mm.
Relative humidity in Hartford during August averages 73%. The most humid Augusts were 2009 and 2018 at 82%, and the least humid was 2002 at 60%.
August receives about 5.3 kWh/m²/day of solar energy in Hartford. The sunniest Augusts were 1984, 2015 and 2016 at 5.9 kWh/m²/day, and the cloudiest was 2021 at 4.6.
Average wind speed in Hartford during August is 0.1 m/s. The windiest Augusts were 2023, 2024 and 2025, among others at 0.1 m/s, while the calmest were 2006, 2018 and 2019, among others at 0 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 20.8°C | 21.5°C | 22.3°C | 22.2°C | 22.6°C | +1.8°C |
| Avg High | 26.8°C | 27.7°C | 28.1°C | 28.1°C | 28.4°C | +1.6°C |
| Avg Low | 14.7°C | 15.3°C | 16.5°C | 16.4°C | 16.9°C | +2.2°C |
| Avg Rain | 92 mm | 117 mm | 89 mm | 116 mm | 97 mm | +5 mm |
August temperatures in Hartford have risen by about 1.5°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 5.3°C (1986) to a record high of 38.7°C (2001).
Rainfall in August is about average for rainfall, averaging 103 mm, with a wettest year of 294 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.3°C per decade while lows rose 0.6°C per decade, narrowing the gap between day and night.
One of the best times to visit Hartford
August is one of the best times to visit Hartford. Expect days averaging 27.8°C and nights around 15.9°C (mean 21.9°C) — warmer than Hartford's yearly average — with higher rainfall (103 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 | 29.0°C | 22.1°C | 15.2°C | 35.8°C | 9.9°C | 53 mm | 63% | 0.1 m/s | 5.8 |
| 2024 | 26.8°C | 21.4°C | 16.0°C | 32.8°C | 10.1°C | 135 mm | 79% | 0.1 m/s | 4.9 |
| 2023 | 25.6°C | 20.6°C | 15.7°C | 28.2°C | 11.0°C | 128 mm | 82% | 0.1 m/s | 4.9 |
| 2022 🔥 | 31.1°C | 24.9°C | 18.7°C | 36.9°C | 13.5°C | 70 mm | 66% | 0.1 m/s | 5.5 |
| 2021 | 27.9°C | 23.0°C | 18.1°C | 33.6°C | 12.3°C | 130 mm | 80% | 0.1 m/s | 4.6 |
| 2020 | 30.1°C | 23.8°C | 17.5°C | 35.2°C | 11.2°C | 68 mm | 65% | 0.1 m/s | 5.3 |
| 2019 | 28.2°C | 22.3°C | 16.3°C | 32.0°C | 9.6°C | 106 mm | 72% | 0 m/s | 5.5 |
| 2018 | 28.1°C | 23.3°C | 18.5°C | 33.7°C | 12.9°C | 141 mm | 82% | 0 m/s | 5.2 |
| 2017 | 26.9°C | 21.1°C | 15.3°C | 32.0°C | 10.5°C | 68 mm | 73% | 0.1 m/s | 5.5 |
| 2016 | 30.2°C | 24.0°C | 17.7°C | 34.2°C | 11.5°C | 102 mm | 69% | 0.1 m/s | 5.9 |
| 2015 | 30.0°C | 23.5°C | 17.0°C | 34.6°C | 13.0°C | 61 mm | 67% | 0.1 m/s | 5.9 |
| 2014 | 27.1°C | 20.9°C | 14.7°C | 32.9°C | 10.6°C | 84 mm | 72% | 0.1 m/s | 5.4 |
| 2013 | 26.1°C | 20.5°C | 15.0°C | 30.6°C | 10.4°C | 109 mm | 76% | 0.1 m/s | 5.2 |
| 2012 | 28.9°C | 22.7°C | 16.5°C | 34.7°C | 11.2°C | 112 mm | 71% | 0.1 m/s | 5.6 |
| 2011 🌧️ | 26.5°C | 21.3°C | 16.2°C | 31.7°C | 11.3°C | 294 mm | 80% | 0.1 m/s | 5.2 |
| 2010 | 29.1°C | 22.8°C | 16.5°C | 35.0°C | 11.5°C | 88 mm | 68% | 0.1 m/s | 5.1 |
| 2009 | 26.6°C | 21.9°C | 17.1°C | 31.3°C | 11.4°C | 85 mm | 82% | 0.1 m/s | 5.2 |
| 2008 | 25.5°C | 19.9°C | 14.4°C | 27.8°C | 9.0°C | 105 mm | 79% | 0.1 m/s | 5.6 |
| 2007 | 29.0°C | 22.5°C | 16.0°C | 35.6°C | 9.5°C | 46 mm | 68% | 0.1 m/s | 5.3 |
| 2006 | 26.2°C | 21.0°C | 15.8°C | 33.4°C | 10.1°C | 128 mm | 77% | 0 m/s | 5.2 |
| 2005 | 30.4°C | 24.3°C | 18.1°C | 36.3°C | 12.9°C | 65 mm | 68% | 0 m/s | 5 |
| 2004 | 26.9°C | 21.5°C | 16.0°C | 32.2°C | 9.9°C | 136 mm | 78% | 0.1 m/s | 5 |
| 2003 | 28.1°C | 22.9°C | 17.7°C | 31.8°C | 10.8°C | 119 mm | 78% | 0.1 m/s | 5 |
| 2002 | 31.0°C | 24.0°C | 17.1°C | 38.2°C | 11.6°C | 68 mm | 60% | 0.1 m/s | 5.4 |
| 2001 | 30.9°C | 24.4°C | 17.8°C | 38.7°C | 12.2°C | 68 mm | 66% | 0.1 m/s | 5.2 |
| 2000 | 25.9°C | 20.3°C | 14.8°C | 31.2°C | 9.2°C | 74 mm | 78% | 0.1 m/s | 5 |
| 1999 | 28.5°C | 22.2°C | 15.8°C | 35.2°C | 11.2°C | 63 mm | 64% | 0.1 m/s | 5 |
| 1998 | 29.5°C | 23.0°C | 16.4°C | 33.3°C | 10.1°C | 53 mm | 67% | 0.1 m/s | 5.4 |
| 1997 | 26.5°C | 20.6°C | 14.6°C | 32.3°C | 11.1°C | 131 mm | 73% | 0.1 m/s | 5.1 |
| 1996 | 27.5°C | 21.4°C | 15.3°C | 31.3°C | 11.5°C | 53 mm | 74% | 0.1 m/s | 5.4 |
| 1995 | 30.1°C | 22.6°C | 15.2°C | 36.0°C | 9.3°C | 65 mm | 61% | 0.1 m/s | 5.7 |
| 1994 | 26.1°C | 20.2°C | 14.3°C | 31.9°C | 9.1°C | 161 mm | 76% | 0.1 m/s | 5.1 |
| 1993 | 29.5°C | 22.7°C | 15.9°C | 36.0°C | 10.7°C | 64 mm | 67% | 0.1 m/s | 5.3 |
| 1992 | 25.4°C | 19.6°C | 13.8°C | 31.2°C | 8.5°C | 137 mm | 77% | 0.1 m/s | 5.1 |
| 1991 | 27.3°C | 21.6°C | 15.8°C | 32.2°C | 11.7°C | 222 mm | 75% | 0.1 m/s | 5.2 |
| 1990 | 26.1°C | 21.0°C | 16.0°C | 32.1°C | 10.7°C | 219 mm | 80% | 0.1 m/s | 4.7 |
| 1989 | 24.8°C | 19.9°C | 14.9°C | 30.0°C | 7.3°C | 165 mm | 80% | 0.1 m/s | 5.1 |
| 1988 | 28.9°C | 22.7°C | 16.5°C | 35.6°C | 7.8°C | 78 mm | 70% | 0.1 m/s | 5.4 |
| 1987 | 27.1°C | 20.5°C | 13.9°C | 34.7°C | 8.5°C | 105 mm | 68% | 0.1 m/s | 5.1 |
| 1986 | 25.1°C | 19.5°C | 14.0°C | 29.9°C | 5.3°C | 103 mm | 75% | 0.1 m/s | 5 |
| 1985 | 26.5°C | 20.4°C | 14.2°C | 32.3°C | 10.3°C | 126 mm | 73% | 0.1 m/s | 5.1 |
| 1984 | 26.9°C | 21.3°C | 15.8°C | 29.5°C | 8.5°C | 36 mm | 79% | 0.1 m/s | 5.9 |
| 1983 | 28.3°C | 21.9°C | 15.4°C | 32.8°C | 9.6°C | 95 mm | 71% | 0.1 m/s | — |
| 1982 ❄️ | 25.4°C | 19.4°C | 13.3°C | 29.2°C | 5.6°C | 79 mm | 72% | 0.1 m/s | — |
| 1981 | 28.6°C | 21.5°C | 14.5°C | 32.8°C | 8.9°C | 40 mm | 63% | 0.1 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 27.8°C with lows near 15.9°C (mean 21.9°C), based on 45 years of NASA POWER data.
August averages 103 mm of rainfall in Hartford, about average for rainfall. The wettest on record was 294 mm in 2011.
The hottest August reached 38.7°C in 2001. The coldest dipped to 5.3°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.5°C. Daytime highs moved from 27.1°C to 28.1°C and overnight lows from 14.6°C to 16.7°C over the same span.
August is one of the warmer months of the year in Hartford and about average for rainfall, so plan for around 27.8°C daytime highs and 15.9°C at night.
Not quite — August is the 11th coolest month in Hartford, averaging 21.9°C.
For August in Hartford, pack light layers you can adjust through the day, with typical highs of 27.8°C and lows of 15.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 73% — moderately humid.
Average wind speed in August is 0.1 m/s. The windiest August on record averaged 0.1 m/s (1981).
The wettest August on record was 2011 with 294 mm. On average, August sees 103 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 Hartford 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.
