August is one of the warmer months of the year in Mililani, with average highs near 27.8°C and lows around 24.8°C (mean 26.3°C). It is one of the drier months, averaging 45 mm of rainfall and 74% relative humidity across the period.
August is one of the warmer months of the year in Mililani. Across 45 years of records, the warmest August in Mililani was 2019 — when the month averaged 27.7°C — while the coldest was 1983 at 24.6°C. Typical August days reach 27.8°C with nights near 24.8°C. The long-term trend is warming, about 0.3°C per decade.
August is one of the drier months in Mililani, averaging 45 mm of rainfall. The wettest August on record was 1983 with 345 mm, while the driest was 2007 at 5 mm.
Relative humidity in Mililani during August averages 74%. The most humid August was 1982 at 81%, and the least humid was 2005 at 70%.
August receives about 6.6 kWh/m²/day of solar energy in Mililani. The sunniest Augusts were 2005, 2022 and 2023, among others at 7.1 kWh/m²/day, and the cloudiest was 1986 at 5.8.
Average wind speed in Mililani during August is 6 m/s. The windiest Augusts were 1999, 2001 and 2003, among others at 6.9 m/s, while the calmest was 2015 at 4.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 25.7°C | 26.1°C | 26.3°C | 26.6°C | 26.9°C | +1.2°C |
| Avg High | 27.2°C | 27.6°C | 27.8°C | 28.1°C | 28.5°C | +1.3°C |
| Avg Low | 24.3°C | 24.7°C | 24.8°C | 25.1°C | 25.2°C | +0.9°C |
| Avg Rain | 96 mm | 12 mm | 32 mm | 55 mm | 31 mm | -65 mm |
August temperatures in Mililani have risen by about 1.5°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 22.5°C (1983) to a record high of 30°C (2019).
Rainfall in August is one of the drier months, averaging 45 mm, with a wettest year of 345 mm.
A quieter season to visit Mililani
If your dates are flexible, the more temperate months of February and March tend to be the most comfortable for visiting Mililani. That said, August — with days averaging 27.8°C and nights around 24.8°C (mean 26.3°C) and moderate rainfall (45 mm) — can still be rewarding for travellers who don't mind the warmth, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 29.1°C | 27.4°C | 25.7°C | 29.9°C | 24.9°C | 8 mm | 71% | 5.7 m/s | 6.8 |
| 2024 | 28.5°C | 27.0°C | 25.4°C | 29.6°C | 24.4°C | 25 mm | 75% | 6.3 m/s | 6.6 |
| 2023 | 28.6°C | 26.9°C | 25.2°C | 29.2°C | 24.3°C | 6 mm | 71% | 6.6 m/s | 7.1 |
| 2022 | 28.5°C | 26.8°C | 25.1°C | 29.4°C | 24.4°C | 58 mm | 73% | 5.2 m/s | 7.1 |
| 2021 | 27.8°C | 26.2°C | 24.6°C | 28.7°C | 24.0°C | 58 mm | 74% | 6 m/s | 7 |
| 2020 | 28.3°C | 26.8°C | 25.2°C | 29.2°C | 24.5°C | 32 mm | 74% | 6.2 m/s | 7 |
| 2019 🔥 | 29.2°C | 27.7°C | 26.2°C | 30.0°C | 25.5°C | 35 mm | 75% | 5.2 m/s | 6.9 |
| 2018 | 27.9°C | 26.5°C | 25.2°C | 29.4°C | 24.4°C | 110 mm | 78% | 6.8 m/s | 5.9 |
| 2017 | 28.6°C | 27.0°C | 25.5°C | 29.1°C | 24.9°C | 48 mm | 73% | 5.9 m/s | 6.9 |
| 2016 | 27.9°C | 26.6°C | 25.3°C | 28.7°C | 24.6°C | 103 mm | 78% | 5.8 m/s | 6.5 |
| 2015 | 29.0°C | 27.6°C | 26.2°C | 29.9°C | 25.3°C | 148 mm | 77% | 4.5 m/s | 6.4 |
| 2014 | 28.4°C | 26.8°C | 25.2°C | 29.4°C | 24.6°C | 38 mm | 74% | 5.6 m/s | 6.7 |
| 2013 | 28.1°C | 26.4°C | 24.8°C | 29.4°C | 23.9°C | 39 mm | 73% | 5.9 m/s | 7 |
| 2012 | 27.2°C | 25.6°C | 24.0°C | 28.2°C | 23.5°C | 16 mm | 73% | 6.2 m/s | 6.9 |
| 2011 | 27.3°C | 25.8°C | 24.2°C | 28.0°C | 23.7°C | 7 mm | 72% | 6.4 m/s | 6.7 |
| 2010 | 27.4°C | 25.8°C | 24.3°C | 28.2°C | 23.9°C | 7 mm | 72% | 6.5 m/s | 6.8 |
| 2009 | 27.9°C | 26.4°C | 25.0°C | 28.9°C | 24.5°C | 28 mm | 74% | 6.3 m/s | 6.6 |
| 2008 | 27.6°C | 26.1°C | 24.5°C | 28.2°C | 24.0°C | 38 mm | 72% | 6.2 m/s | 6.9 |
| 2007 | 28.1°C | 26.5°C | 24.9°C | 29.1°C | 24.5°C | 5 mm | 72% | 6.3 m/s | 6.9 |
| 2006 | 27.9°C | 26.4°C | 24.9°C | 29.6°C | 24.1°C | 23 mm | 73% | 5.9 m/s | 6.7 |
| 2005 | 28.2°C | 26.5°C | 24.8°C | 29.2°C | 24.1°C | 22 mm | 70% | 5.8 m/s | 7.1 |
| 2004 | 28.3°C | 26.9°C | 25.5°C | 29.8°C | 24.9°C | 91 mm | 75% | 6 m/s | 6.5 |
| 2003 | 27.7°C | 26.3°C | 24.8°C | 28.8°C | 23.9°C | 19 mm | 74% | 6.9 m/s | 6.8 |
| 2002 | 27.3°C | 26.0°C | 24.6°C | 28.2°C | 23.7°C | 54 mm | 77% | 6.1 m/s | 6.2 |
| 2001 | 27.4°C | 26.0°C | 24.6°C | 28.6°C | 23.9°C | 26 mm | 75% | 6.9 m/s | 6.4 |
| 2000 | 27.2°C | 25.8°C | 24.3°C | 27.9°C | 23.6°C | 13 mm | 73% | 6.5 m/s | 6.8 |
| 1999 | 27.2°C | 25.6°C | 24.1°C | 28.3°C | 22.8°C | 6 mm | 71% | 6.9 m/s | 6.8 |
| 1998 | 27.3°C | 25.9°C | 24.4°C | 28.9°C | 23.1°C | 7 mm | 71% | 6.4 m/s | 6.6 |
| 1997 | 28.0°C | 26.5°C | 24.9°C | 29.4°C | 23.9°C | 9 mm | 72% | 5.4 m/s | 6.9 |
| 1996 | 28.5°C | 26.9°C | 25.2°C | 29.6°C | 24.3°C | 7 mm | 72% | 5.5 m/s | 7.1 |
| 1995 | 27.4°C | 26.0°C | 24.6°C | 28.4°C | 24.0°C | 6 mm | 73% | 6.7 m/s | 6.6 |
| 1994 | 27.9°C | 26.5°C | 25.0°C | 28.8°C | 24.0°C | 8 mm | 74% | 6.3 m/s | 6.3 |
| 1993 | 27.8°C | 26.3°C | 24.7°C | 29.2°C | 23.6°C | 6 mm | 73% | 5.8 m/s | 6.3 |
| 1992 | 27.3°C | 26.1°C | 24.9°C | 28.2°C | 24.2°C | 13 mm | 75% | 6.9 m/s | 6 |
| 1991 | 27.0°C | 25.7°C | 24.3°C | 28.3°C | 23.3°C | 33 mm | 77% | 6.3 m/s | 6.1 |
| 1990 | 27.3°C | 25.8°C | 24.4°C | 28.0°C | 23.5°C | 25 mm | 75% | 6 m/s | 6.4 |
| 1989 | 27.3°C | 25.7°C | 24.1°C | 28.2°C | 23.1°C | 18 mm | 74% | 5.5 m/s | 6.3 |
| 1988 | 27.2°C | 25.7°C | 24.2°C | 28.0°C | 23.7°C | 60 mm | 75% | 6 m/s | 6.7 |
| 1987 | 28.3°C | 26.6°C | 25.0°C | 29.4°C | 24.1°C | 26 mm | 72% | 5.2 m/s | 6.7 |
| 1986 | 27.7°C | 26.3°C | 25.0°C | 28.8°C | 23.8°C | 50 mm | 78% | 5.7 m/s | 5.8 |
| 1985 | 27.2°C | 25.6°C | 24.1°C | 29.7°C | 23.4°C | 70 mm | 76% | 5.5 m/s | 6.3 |
| 1984 | 27.0°C | 25.5°C | 24.0°C | 28.0°C | 23.4°C | 44 mm | 75% | 5.5 m/s | 6.5 |
| 1983 ❄️ 🌧️ | 25.9°C | 24.6°C | 23.3°C | 27.4°C | 22.5°C | 345 mm | 80% | 6 m/s | — |
| 1982 | 26.7°C | 25.5°C | 24.4°C | 27.2°C | 23.6°C | 201 mm | 81% | 6.4 m/s | — |
| 1981 | 27.3°C | 25.9°C | 24.4°C | 28.3°C | 24.0°C | 54 mm | 77% | 5.5 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 24.8°C (mean 26.3°C), based on 45 years of NASA POWER data.
August averages 45 mm of rainfall in Mililani, one of the drier months. The wettest on record was 345 mm in 1983.
The hottest August reached 30°C in 2019. The coldest dipped to 22.5°C in 1983.
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 26.8°C to 28.5°C and overnight lows from 24°C to 25.2°C over the same span.
August is one of the warmer months of the year in Mililani and one of the drier months, so plan for around 27.8°C daytime highs and 24.8°C at night.
Not quite — August is the 11th coolest month in Mililani, averaging 26.3°C.
For August in Mililani, pack light layers you can adjust through the day, with typical highs of 27.8°C and lows of 24.8°C.
Relative humidity in August averages 74% — moderately humid.
Average wind speed in August is 6 m/s. The windiest August on record averaged 6.9 m/s (1992).
The wettest August on record was 1983 with 345 mm. On average, August sees 45 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 Mililani 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.
