May is close to Kailua's year-round average, with average highs near 24.9°C and lows around 23.3°C (mean 24.1°C). It is one of the drier months, averaging 30 mm of rainfall and 77% relative humidity across the period.
May is close to Kailua's year-round average. Across 45 years of records, the warmest May in Kailua was 2025 — when the month averaged 25.3°C — while the coldest were 1985 and 1987 at 22.6°C. Typical May days reach 24.9°C with nights near 23.3°C. The long-term trend is warming, about 0.4°C per decade.
May is one of the drier months in Kailua, averaging 30 mm of rainfall. The wettest May on record was 2002 with 96 mm, while the driest was 2007 at 5 mm.
Relative humidity in Kailua during May averages 77%. The most humid May was 2002 at 82%, and the least humid was 2008 at 74%.
May receives about 6.7 kWh/m²/day of solar energy in Kailua. The sunniest Mays were 2017, 2020 and 2025 at 7.2 kWh/m²/day, and the cloudiest was 2018 at 5.8.
Average wind speed in Kailua during May is 5.8 m/s. The windiest May was 1998 at 7.9 m/s, while the calmest was 2009 at 3.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.4°C | 23.7°C | 24.3°C | 24.5°C | 24.8°C | +1.4°C |
| Avg High | 24.1°C | 24.5°C | 25.2°C | 25.3°C | 25.6°C | +1.5°C |
| Avg Low | 22.7°C | 23.0°C | 23.5°C | 23.7°C | 23.9°C | +1.2°C |
| Avg Rain | 36 mm | 20 mm | 26 mm | 38 mm | 31 mm | -4 mm |
May temperatures in Kailua have risen by about 1.5°C between 1981–1985 and 2021–2025.
May has ranged from a record low of 19.4°C (1987) to a record high of 27.4°C (2019).
Rainfall in May is one of the drier months, averaging 30 mm, with a wettest year of 96 mm.
One of the best times to visit Kailua
May is one of the best times to visit Kailua. Expect days averaging 24.9°C and nights around 23.3°C (mean 24.1°C) — close to Kailua's yearly average — with moderate rainfall (30 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 🔥 | 26.2°C | 25.3°C | 24.5°C | 27.0°C | 23.7°C | 11 mm | 76% | 6.7 m/s | 7.2 |
| 2024 | 25.5°C | 24.7°C | 23.8°C | 26.7°C | 22.9°C | 43 mm | 78% | 5.5 m/s | 6.4 |
| 2023 | 25.4°C | 24.5°C | 23.7°C | 26.4°C | 22.5°C | 25 mm | 76% | 5.8 m/s | 6.7 |
| 2022 | 25.4°C | 24.6°C | 23.8°C | 26.6°C | 23.3°C | 51 mm | 78% | 6 m/s | 6.5 |
| 2021 | 25.5°C | 24.7°C | 23.9°C | 26.9°C | 23.0°C | 25 mm | 77% | 5.9 m/s | 7 |
| 2020 | 25.5°C | 24.7°C | 23.9°C | 26.4°C | 23.0°C | 33 mm | 77% | 6 m/s | 7.2 |
| 2019 | 26.0°C | 25.0°C | 24.1°C | 27.4°C | 21.2°C | 42 mm | 78% | 4.7 m/s | 7 |
| 2018 | 24.9°C | 24.2°C | 23.5°C | 25.9°C | 22.0°C | 47 mm | 80% | 5.9 m/s | 5.8 |
| 2017 | 25.9°C | 25.1°C | 24.2°C | 26.9°C | 23.0°C | 28 mm | 77% | 5.4 m/s | 7.2 |
| 2016 | 25.5°C | 24.7°C | 23.9°C | 26.9°C | 22.5°C | 53 mm | 78% | 5.4 m/s | 6.6 |
| 2015 | 24.6°C | 23.9°C | 23.1°C | 26.1°C | 21.8°C | 37 mm | 76% | 6.1 m/s | 6.8 |
| 2014 | 25.8°C | 24.9°C | 23.9°C | 27.0°C | 22.2°C | 51 mm | 77% | 3.8 m/s | 6.5 |
| 2013 | 25.6°C | 24.7°C | 23.8°C | 27.0°C | 22.3°C | 35 mm | 75% | 4.7 m/s | 6.7 |
| 2012 | 24.5°C | 23.7°C | 22.9°C | 25.5°C | 21.7°C | 11 mm | 75% | 6.8 m/s | 7.1 |
| 2011 | 25.4°C | 24.6°C | 23.9°C | 26.5°C | 23.2°C | 58 mm | 77% | 6.6 m/s | 6.4 |
| 2010 | 25.1°C | 24.3°C | 23.6°C | 25.7°C | 23.2°C | 14 mm | 76% | 6.4 m/s | 7 |
| 2009 | 25.5°C | 24.4°C | 23.4°C | 27.2°C | 22.2°C | 12 mm | 74% | 3.2 m/s | 7.1 |
| 2008 | 25.4°C | 24.5°C | 23.7°C | 26.5°C | 22.9°C | 10 mm | 74% | 5.5 m/s | 6.9 |
| 2007 | 25.3°C | 24.5°C | 23.7°C | 26.6°C | 23.1°C | 5 mm | 75% | 5.8 m/s | 7.1 |
| 2006 | 24.3°C | 23.5°C | 22.7°C | 25.7°C | 20.9°C | 24 mm | 76% | 6.1 m/s | 7.1 |
| 2005 | 25.7°C | 24.9°C | 24.2°C | 26.6°C | 23.3°C | 26 mm | 78% | 5.8 m/s | 7.1 |
| 2004 | 25.7°C | 24.9°C | 24.0°C | 26.7°C | 22.8°C | 61 mm | 79% | 5.3 m/s | 6.6 |
| 2003 | 25.4°C | 24.5°C | 23.6°C | 26.4°C | 23.0°C | 10 mm | 76% | 6 m/s | 7 |
| 2002 🌧️ | 25.3°C | 24.5°C | 23.7°C | 26.9°C | 22.9°C | 96 mm | 82% | 5 m/s | 6.1 |
| 2001 | 24.8°C | 23.9°C | 23.1°C | 26.9°C | 22.1°C | 11 mm | 77% | 5.7 m/s | 7 |
| 2000 | 24.3°C | 23.5°C | 22.8°C | 24.7°C | 22.2°C | 8 mm | 77% | 6.3 m/s | 7 |
| 1999 | 24.9°C | 24.1°C | 23.3°C | 26.0°C | 22.7°C | 25 mm | 75% | 5.5 m/s | 6.8 |
| 1998 | 23.4°C | 22.8°C | 22.3°C | 24.1°C | 21.6°C | 25 mm | 76% | 7.9 m/s | 6.3 |
| 1997 | 24.4°C | 23.5°C | 22.6°C | 25.8°C | 21.7°C | 38 mm | 75% | 5.4 m/s | 6.7 |
| 1996 | 25.3°C | 24.5°C | 23.6°C | 26.9°C | 21.4°C | 7 mm | 76% | 5 m/s | 6.8 |
| 1995 | 24.1°C | 23.4°C | 22.7°C | 25.4°C | 21.1°C | 12 mm | 77% | 6 m/s | 6.6 |
| 1994 | 24.5°C | 23.8°C | 23.1°C | 25.3°C | 22.4°C | 16 mm | 76% | 6.7 m/s | 6.3 |
| 1993 | 24.2°C | 23.5°C | 22.9°C | 25.0°C | 21.8°C | 10 mm | 75% | 6.3 m/s | 6.4 |
| 1992 | 25.2°C | 24.3°C | 23.3°C | 26.9°C | 21.1°C | 22 mm | 76% | 4.4 m/s | 6 |
| 1991 | 24.6°C | 23.8°C | 23.1°C | 26.2°C | 21.6°C | 13 mm | 75% | 5.9 m/s | 6.4 |
| 1990 | 24.0°C | 23.3°C | 22.6°C | 24.9°C | 21.6°C | 33 mm | 78% | 6.8 m/s | 6.4 |
| 1989 | 24.3°C | 23.6°C | 22.9°C | 25.9°C | 20.3°C | 44 mm | 78% | 6.3 m/s | 6.4 |
| 1988 | 24.8°C | 24.2°C | 23.5°C | 26.1°C | 21.8°C | 22 mm | 79% | 6.3 m/s | 6.4 |
| 1987 | 23.5°C | 22.6°C | 21.8°C | 25.3°C | 19.4°C | 41 mm | 77% | 5 m/s | 6.2 |
| 1986 | 24.6°C | 23.8°C | 23.1°C | 26.2°C | 21.7°C | 34 mm | 79% | 5.4 m/s | 6.1 |
| 1985 ❄️ | 23.3°C | 22.6°C | 22.0°C | 24.2°C | 20.3°C | 57 mm | 80% | 6.4 m/s | 6 |
| 1984 | 24.7°C | 23.9°C | 23.2°C | 25.7°C | 22.4°C | 25 mm | 78% | 6 m/s | 6.6 |
| 1983 | 23.6°C | 22.9°C | 22.2°C | 24.7°C | 21.0°C | 30 mm | 78% | 6 m/s | — |
| 1982 | 23.8°C | 23.1°C | 22.4°C | 25.1°C | 21.5°C | 52 mm | 81% | 5.6 m/s | — |
| 1981 | 24.7°C | 23.8°C | 23.0°C | 25.7°C | 21.2°C | 15 mm | 76% | 5.5 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 24.9°C with lows near 23.3°C (mean 24.1°C), based on 45 years of NASA POWER data.
May averages 30 mm of rainfall in Kailua, one of the drier months. The wettest on record was 96 mm in 2002.
The hottest May reached 27.4°C in 2019. The coldest dipped to 19.4°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.5°C. Daytime highs moved from 24°C to 25.6°C and overnight lows from 22.6°C to 23.9°C over the same span.
May is close to Kailua's year-round average and one of the drier months, so plan for around 24.9°C daytime highs and 23.3°C at night.
Not quite — May is the 6th coolest month in Kailua, averaging 24.1°C.
For May in Kailua, pack light layers you can adjust through the day, with typical highs of 24.9°C and lows of 23.3°C.
Relative humidity in May averages 77% — quite humid.
Average wind speed in May is 5.8 m/s. The windiest May on record averaged 7.9 m/s (1998).
The wettest May on record was 2002 with 96 mm. On average, May sees 30 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 Kailua behaves each May, 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 May specifically, along with year-by-year records and how the month has changed over the decades.
