May is one of the warmer months of the year in Perth, with average highs near 12.7°C and lows around 5.6°C (mean 9.1°C). It is one of the drier months, averaging 67 mm of rainfall and 84% relative humidity across the period.
May is one of the warmer months of the year in Perth. Across 45 years of records, the warmest May in Perth was 2024 — when the month averaged 12.2°C — while the coldest was 1996 at 6.6°C. Typical May days reach 12.7°C with nights near 5.6°C. The long-term trend is warming, about 0.3°C per decade.
May is one of the drier months in Perth, averaging 67 mm of rainfall. The wettest May on record was 1986 with 123 mm, while the driest was 1994 at 22 mm.
Relative humidity in Perth during May averages 84%. The most humid May was 2024 at 88%, and the least humid was 2025 at 79%.
May receives about 4.6 kWh/m²/day of solar energy in Perth. The sunniest May was 2025 at 5.9 kWh/m²/day, and the cloudiest was 1986 at 3.9.
Average wind speed in Perth during May is 3.2 m/s. The windiest May was 1986 at 4.6 m/s, while the calmest were 1990 and 2023 at 2.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 8.7°C | 8.8°C | 9.4°C | 9.1°C | 10.3°C | +1.6°C |
| Avg High | 12.2°C | 12.4°C | 12.9°C | 12.7°C | 14.0°C | +1.8°C |
| Avg Low | 5.1°C | 5.3°C | 5.9°C | 5.5°C | 6.6°C | +1.5°C |
| Avg Rain | 70 mm | 60 mm | 71 mm | 69 mm | 67 mm | -2 mm |
May temperatures in Perth have risen by about 1.8°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -1.6°C (2015) to a record high of 22.2°C (2017).
Rainfall in May is one of the drier months, averaging 67 mm, with a wettest year of 123 mm.
A good time to visit Perth
May is a good time to visit Perth, with days averaging 12.7°C and nights around 5.6°C (mean 9.1°C, warmer than Perth's yearly average) and moderate rainfall. July and August are marginally more temperate, but May still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 15.5°C | 10.9°C | 6.3°C | 19.1°C | 1.5°C | 38 mm | 79% | 3.1 m/s | 5.9 |
| 2024 🔥 | 15.4°C | 12.2°C | 8.9°C | 20.2°C | 6.5°C | 94 mm | 88% | 2.7 m/s | 4.2 |
| 2023 | 14.2°C | 10.5°C | 6.8°C | 20.1°C | 1.7°C | 47 mm | 85% | 2.3 m/s | 4.5 |
| 2022 | 13.4°C | 10.2°C | 7.0°C | 16.1°C | 3.8°C | 68 mm | 85% | 3.7 m/s | 4.2 |
| 2021 | 11.3°C | 8.2°C | 5.0°C | 18.1°C | -1.2°C | 116 mm | 85% | 2.9 m/s | 4 |
| 2020 | 13.9°C | 9.8°C | 5.8°C | 22.1°C | -0.5°C | 40 mm | 81% | 3.3 m/s | 5.2 |
| 2019 | 12.4°C | 8.9°C | 5.5°C | 18.6°C | -0.5°C | 102 mm | 81% | 2.7 m/s | 4.4 |
| 2018 | 14.6°C | 10.6°C | 6.6°C | 19.6°C | 0.9°C | 39 mm | 85% | 2.9 m/s | 5.1 |
| 2017 | 14.5°C | 10.6°C | 6.7°C | 22.2°C | 2.8°C | 52 mm | 83% | 3.1 m/s | 5 |
| 2016 | 13.0°C | 9.5°C | 6.0°C | 16.1°C | 0.9°C | 44 mm | 84% | 3.4 m/s | 4.9 |
| 2015 | 11.0°C | 7.6°C | 4.2°C | 15.1°C | -1.6°C | 98 mm | 82% | 4.1 m/s | 4.5 |
| 2014 | 12.8°C | 9.7°C | 6.6°C | 16.1°C | 1.1°C | 60 mm | 86% | 2.9 m/s | 4.1 |
| 2013 | 12.2°C | 8.5°C | 4.9°C | 20.1°C | 1.4°C | 65 mm | 85% | 4 m/s | 4.2 |
| 2012 | 11.7°C | 8.1°C | 4.5°C | 20.1°C | -0.6°C | 74 mm | 84% | 2.9 m/s | 4.8 |
| 2011 | 12.4°C | 9.2°C | 6.0°C | 14.9°C | 3.2°C | 100 mm | 84% | 4.4 m/s | 4.6 |
| 2010 | 12.2°C | 8.3°C | 4.4°C | 21.0°C | -0.4°C | 54 mm | 82% | 2.4 m/s | 4.7 |
| 2009 | 12.6°C | 9.1°C | 5.7°C | 19.2°C | 2.4°C | 80 mm | 85% | 4 m/s | 4.9 |
| 2008 | 13.6°C | 10.2°C | 6.7°C | 19.1°C | 2.5°C | 48 mm | 84% | 2.9 m/s | 4.7 |
| 2007 | 12.1°C | 8.8°C | 5.6°C | 15.4°C | 2.0°C | 76 mm | 84% | 3.6 m/s | 4.4 |
| 2006 | 12.4°C | 8.8°C | 5.2°C | 17.8°C | 1.5°C | 86 mm | 83% | 3.5 m/s | 4.6 |
| 2005 | 12.0°C | 8.5°C | 5.0°C | 16.7°C | 0.1°C | 92 mm | 83% | 3.2 m/s | 4.5 |
| 2004 | 13.9°C | 10.2°C | 6.4°C | 18.5°C | 3.1°C | 40 mm | 83% | 2.7 m/s | 4.8 |
| 2003 | 12.1°C | 9.2°C | 6.2°C | 19.0°C | 3.0°C | 102 mm | 87% | 3.6 m/s | 4.2 |
| 2002 | 12.8°C | 9.5°C | 6.2°C | 17.3°C | 1.1°C | 91 mm | 86% | 3.5 m/s | 4.1 |
| 2001 | 14.3°C | 10.2°C | 6.1°C | 20.7°C | 1.4°C | 29 mm | 83% | 2.6 m/s | 5 |
| 2000 | 12.8°C | 9.2°C | 5.5°C | 18.7°C | 2.9°C | 68 mm | 85% | 2.7 m/s | 4.8 |
| 1999 | 12.4°C | 9.4°C | 6.5°C | 17.1°C | 3.3°C | 83 mm | 86% | 3.4 m/s | 4.4 |
| 1998 | 13.4°C | 9.7°C | 6.0°C | 17.8°C | 1.9°C | 47 mm | 85% | 3.3 m/s | 4.9 |
| 1997 | 11.9°C | 8.6°C | 5.2°C | 19.2°C | -1.4°C | 101 mm | 86% | 3.2 m/s | 4.5 |
| 1996 ❄️ | 10.0°C | 6.6°C | 3.3°C | 14.1°C | -0.5°C | 58 mm | 84% | 3.6 m/s | 4.4 |
| 1995 | 12.0°C | 8.4°C | 4.7°C | 18.0°C | -1.3°C | 61 mm | 83% | 3 m/s | 4.6 |
| 1994 | 11.4°C | 7.8°C | 4.2°C | 14.9°C | 0.7°C | 22 mm | 81% | 3.7 m/s | 4.8 |
| 1993 | 12.0°C | 8.6°C | 5.1°C | 16.4°C | 1.1°C | 119 mm | 85% | 3.4 m/s | 4.1 |
| 1992 | 13.4°C | 9.8°C | 6.2°C | 17.9°C | 0.5°C | 42 mm | 85% | 4 m/s | 5.2 |
| 1991 | 13.2°C | 9.2°C | 5.2°C | 18.3°C | 1.8°C | 30 mm | 82% | 3 m/s | 4.4 |
| 1990 | 13.9°C | 10.2°C | 6.4°C | 21.1°C | 2.1°C | 40 mm | 82% | 2.3 m/s | 4.4 |
| 1989 | 13.2°C | 9.3°C | 5.4°C | 18.5°C | 1.1°C | 35 mm | 83% | 3.3 m/s | 4.7 |
| 1988 | 12.6°C | 9.2°C | 5.9°C | 19.1°C | 2.0°C | 62 mm | 85% | 3 m/s | 4.4 |
| 1987 | 11.7°C | 7.9°C | 4.1°C | 15.4°C | 0.2°C | 67 mm | 82% | 3.4 m/s | 4.5 |
| 1986 🌧️ | 11.5°C | 8.5°C | 5.5°C | 16.4°C | 2.6°C | 123 mm | 86% | 4.6 m/s | 3.9 |
| 1985 | 12.1°C | 8.6°C | 5.1°C | 17.5°C | -0.1°C | 84 mm | 84% | 3.3 m/s | 4.1 |
| 1984 | 12.9°C | 8.8°C | 4.6°C | 18.8°C | 0.0°C | 24 mm | 79% | 2.6 m/s | 4.9 |
| 1983 | 10.7°C | 7.8°C | 4.9°C | 13.8°C | 1.6°C | 100 mm | 87% | 3.2 m/s | — |
| 1982 | 12.5°C | 8.5°C | 4.5°C | 19.4°C | -0.9°C | 47 mm | 83% | 3 m/s | — |
| 1981 | 12.7°C | 9.4°C | 6.1°C | 16.6°C | -1.2°C | 85 mm | 86% | 3.2 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 12.7°C with lows near 5.6°C (mean 9.1°C), based on 45 years of NASA POWER data.
May averages 67 mm of rainfall in Perth, one of the drier months. The wettest on record was 123 mm in 1986.
The hottest May reached 22.2°C in 2017. The coldest dipped to -1.6°C in 2015.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.8°C. Daytime highs moved from 12.2°C to 14°C and overnight lows from 5°C to 6.8°C over the same span.
May is one of the warmer months of the year in Perth and one of the drier months, so plan for around 12.7°C daytime highs and 5.6°C at night.
Not quite — May is the 8th coolest month in Perth, averaging 9.1°C.
For May in Perth, pack warm layers and a jacket for chilly mornings, with typical highs of 12.7°C and lows of 5.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 84% — quite humid.
Average wind speed in May is 3.2 m/s. The windiest May on record averaged 4.6 m/s (1986).
The wettest May on record was 1986 with 123 mm. On average, May sees 67 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 Perth 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.
