August is one of the warmer months of the year in Chatham, with average highs near 24.3°C and lows around 13.4°C (mean 18.9°C). It is about average for rainfall, averaging 79 mm of rainfall and 76% relative humidity across the period.
August is one of the warmer months of the year in Chatham. Across 45 years of records, the warmest August in Chatham was 2021 — when the month averaged 22.3°C — while the coldest was 1982 at 15.2°C. Typical August days reach 24.3°C with nights near 13.4°C. The long-term trend is warming, about 0.7°C per decade.
August is about average for rainfall in Chatham, averaging 79 mm of rainfall. The wettest August on record was 1991 with 181 mm, while the driest was 2025 at 17 mm.
Relative humidity in Chatham during August averages 76%. The most humid August was 2011 at 87%, and the least humid was 2025 at 61%.
August receives about 4.9 kWh/m²/day of solar energy in Chatham. The sunniest August was 2025 at 5.6 kWh/m²/day, and the cloudiest were 1988, 2008 and 2023 at 4.2.
Average wind speed in Chatham during August is 0.3 m/s. The windiest Augusts were 2023, 2024 and 2025, among others at 0.3 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.5°C | 18.7°C | 18.6°C | 19.7°C | 20.5°C | +3°C |
| Avg High | 22.5°C | 24.3°C | 23.9°C | 25.1°C | 26.5°C | +4°C |
| Avg Low | 12.5°C | 13.2°C | 13.3°C | 14.2°C | 14.4°C | +1.9°C |
| Avg Rain | 111 mm | 78 mm | 77 mm | 69 mm | 55 mm | -56 mm |
August temperatures in Chatham have risen by about 3°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 4.1°C (1986) to a record high of 38.6°C (2025).
Rainfall in August is about average for rainfall, averaging 79 mm, with a wettest year of 181 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.9°C per decade while lows rose 0.5°C per decade, widening the gap between day and night.
One of the best times to visit Chatham
August is one of the best times to visit Chatham. Expect days averaging 24.3°C and nights around 13.4°C (mean 18.9°C) — warmer than Chatham's yearly average — with moderate rainfall (79 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 | 27.7°C | 20.7°C | 13.8°C | 38.6°C | 8.4°C | 17 mm | 61% | 0.3 m/s | 5.6 |
| 2024 | 26.9°C | 20.8°C | 14.8°C | 33.4°C | 8.8°C | 56 mm | 71% | 0.3 m/s | 5 |
| 2023 | 23.3°C | 18.2°C | 13.1°C | 27.0°C | 8.5°C | 106 mm | 78% | 0.3 m/s | 4.2 |
| 2022 | 26.6°C | 20.7°C | 14.8°C | 33.2°C | 9.5°C | 65 mm | 73% | 0.3 m/s | 4.7 |
| 2021 🔥 | 28.6°C | 22.3°C | 15.9°C | 35.5°C | 11.1°C | 39 mm | 68% | 0.3 m/s | 5.2 |
| 2020 | 25.9°C | 20.0°C | 14.1°C | 32.1°C | 7.5°C | 44 mm | 69% | 0.3 m/s | 5.4 |
| 2019 | 25.8°C | 19.9°C | 13.9°C | 31.1°C | 9.7°C | 46 mm | 72% | 0.3 m/s | 5.1 |
| 2018 | 27.2°C | 21.3°C | 15.5°C | 33.5°C | 10.4°C | 75 mm | 74% | 0.3 m/s | 4.9 |
| 2017 | 25.6°C | 19.4°C | 13.2°C | 30.4°C | 8.8°C | 31 mm | 68% | 0.3 m/s | 5.1 |
| 2016 | 25.0°C | 19.4°C | 13.9°C | 29.3°C | 9.8°C | 94 mm | 76% | 0.3 m/s | 4.9 |
| 2015 | 26.8°C | 21.2°C | 15.7°C | 32.0°C | 12.2°C | 55 mm | 76% | 0.3 m/s | 5 |
| 2014 | 24.4°C | 19.2°C | 14.0°C | 30.9°C | 9.0°C | 77 mm | 77% | 0.3 m/s | 4.5 |
| 2013 | 23.3°C | 18.1°C | 12.9°C | 28.8°C | 8.1°C | 63 mm | 80% | 0.3 m/s | 4.9 |
| 2012 | 25.8°C | 20.5°C | 15.3°C | 29.9°C | 10.6°C | 78 mm | 79% | 0.3 m/s | 4.6 |
| 2011 | 22.6°C | 18.3°C | 14.0°C | 26.3°C | 9.8°C | 125 mm | 87% | 0.3 m/s | 4.4 |
| 2010 | 24.9°C | 19.2°C | 13.4°C | 30.9°C | 10.0°C | 48 mm | 76% | 0.3 m/s | 5.3 |
| 2009 | 24.8°C | 19.6°C | 14.4°C | 30.9°C | 7.4°C | 65 mm | 77% | 0.3 m/s | 4.9 |
| 2008 | 21.7°C | 17.4°C | 13.1°C | 28.3°C | 8.9°C | 108 mm | 86% | 0.3 m/s | 4.2 |
| 2007 | 23.3°C | 17.8°C | 12.3°C | 28.9°C | 7.8°C | 88 mm | 78% | 0.3 m/s | 5 |
| 2006 | 21.0°C | 16.1°C | 11.2°C | 25.7°C | 6.8°C | 70 mm | 82% | 0.3 m/s | 4.9 |
| 2005 | 25.0°C | 19.4°C | 13.8°C | 31.0°C | 8.3°C | 74 mm | 74% | 0.3 m/s | 4.7 |
| 2004 | 24.2°C | 19.0°C | 13.7°C | 29.3°C | 8.9°C | 87 mm | 77% | 0.3 m/s | 4.7 |
| 2003 | 23.4°C | 18.5°C | 13.6°C | 28.1°C | 6.4°C | 105 mm | 81% | 0.3 m/s | 4.6 |
| 2002 | 25.5°C | 19.7°C | 13.9°C | 34.1°C | 6.4°C | 64 mm | 73% | 0.3 m/s | 5.3 |
| 2001 | 26.4°C | 20.1°C | 13.7°C | 31.4°C | 6.8°C | 32 mm | 69% | 0.3 m/s | 5.1 |
| 2000 | 23.6°C | 18.3°C | 13.0°C | 27.7°C | 8.3°C | 73 mm | 79% | 0.3 m/s | 4.7 |
| 1999 | 24.1°C | 18.6°C | 13.1°C | 30.0°C | 9.5°C | 93 mm | 74% | 0.3 m/s | 4.9 |
| 1998 | 24.8°C | 19.0°C | 13.1°C | 32.5°C | 7.4°C | 99 mm | 73% | 0.3 m/s | 4.9 |
| 1997 | 23.7°C | 18.0°C | 12.3°C | 31.2°C | 7.8°C | 46 mm | 72% | 0.3 m/s | 4.7 |
| 1996 | 25.2°C | 19.2°C | 13.2°C | 32.5°C | 9.5°C | 47 mm | 75% | 0.3 m/s | 5.2 |
| 1995 | 25.0°C | 19.0°C | 13.0°C | 33.4°C | 8.4°C | 46 mm | 69% | 0.3 m/s | 5.4 |
| 1994 | 23.8°C | 18.1°C | 12.4°C | 29.2°C | 7.4°C | 36 mm | 72% | 0.3 m/s | 5.2 |
| 1993 | 25.4°C | 19.6°C | 13.8°C | 29.7°C | 8.5°C | 30 mm | 73% | 0.3 m/s | 5.2 |
| 1992 | 23.4°C | 18.1°C | 12.9°C | 31.0°C | 8.8°C | 66 mm | 78% | 0.3 m/s | 4.8 |
| 1991 🌧️ | 23.3°C | 18.2°C | 13.1°C | 29.0°C | 8.4°C | 181 mm | 82% | 0.3 m/s | 4.7 |
| 1990 | 24.7°C | 19.6°C | 14.6°C | 30.0°C | 7.7°C | 136 mm | 82% | 0.3 m/s | 4.9 |
| 1989 | 22.6°C | 17.8°C | 13.0°C | 26.5°C | 5.9°C | 162 mm | 83% | 0.3 m/s | 4.4 |
| 1988 | 23.3°C | 18.5°C | 13.7°C | 30.1°C | 6.1°C | 148 mm | 82% | 0.3 m/s | 4.2 |
| 1987 | 23.2°C | 17.4°C | 11.6°C | 32.2°C | 6.2°C | 56 mm | 74% | 0.3 m/s | 5 |
| 1986 | 21.1°C | 16.5°C | 11.9°C | 27.4°C | 4.1°C | 145 mm | 84% | 0.3 m/s | 4.3 |
| 1985 | 23.3°C | 17.8°C | 12.3°C | 29.8°C | 7.1°C | 68 mm | 76% | 0.3 m/s | 5 |
| 1984 | 23.9°C | 19.2°C | 14.4°C | 29.0°C | 8.6°C | 78 mm | 84% | 0.3 m/s | 4.8 |
| 1983 | 22.7°C | 17.7°C | 12.7°C | 27.0°C | 7.8°C | 72 mm | 82% | 0.3 m/s | — |
| 1982 ❄️ | 20.0°C | 15.2°C | 10.4°C | 26.3°C | 4.2°C | 135 mm | 83% | 0.3 m/s | — |
| 1981 | 22.1°C | 17.4°C | 12.6°C | 27.7°C | 6.8°C | 133 mm | 85% | 0.3 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 24.3°C with lows near 13.4°C (mean 18.9°C), based on 45 years of NASA POWER data.
August averages 79 mm of rainfall in Chatham, about average for rainfall. The wettest on record was 181 mm in 1991.
The hottest August reached 38.6°C in 2025. The coldest dipped to 4.1°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 3°C. Daytime highs moved from 22.4°C to 26.6°C and overnight lows from 12.5°C to 14.5°C over the same span.
August is one of the warmer months of the year in Chatham and about average for rainfall, so plan for around 24.3°C daytime highs and 13.4°C at night.
Not quite — August is the 11th coolest month in Chatham, averaging 18.9°C.
For August in Chatham, pack light layers you can adjust through the day, with typical highs of 24.3°C and lows of 13.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 76% — quite humid.
Average wind speed in August is 0.3 m/s. The windiest August on record averaged 0.3 m/s (1981).
The wettest August on record was 1991 with 181 mm. On average, August sees 79 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 Chatham 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.
