May is one of the cooler months of the year in Westport, with average highs near 11.1°C and lows around 5.4°C (mean 8.3°C). It is a relatively wet time of year, averaging 165 mm of rainfall and 92% relative humidity across the period.
May is one of the cooler months of the year in Westport. Across 45 years of records, the warmest Mays in Westport were 2019 and 2023 — when the month averaged 10.3°C — while the coldest was 1992 at 5.6°C. Typical May days reach 11.1°C with nights near 5.4°C. The long-term trend is warming, about 0.3°C per decade.
May is a relatively wet time of year in Westport, averaging 165 mm of rainfall. The wettest May on record was 1994 with 298 mm, while the driest was 2008 at 58 mm.
Relative humidity in Westport during May averages 92%. The most humid May was 2023 at 95%, and the least humid was 2008 at 87%.
May receives about 1.9 kWh/m²/day of solar energy in Westport. The sunniest May was 1985 at 2.2 kWh/m²/day, and the cloudiest were 2011, 2016 and 2023 at 1.6.
Average wind speed in Westport during May is 0.4 m/s. The windiest Mays were 1996, 2002 and 2009, among others at 0.5 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.7°C | 8.0°C | 8.2°C | 8.6°C | 9.0°C | +1.3°C |
| Avg High | 10.7°C | 10.8°C | 11.0°C | 11.3°C | 11.7°C | +1°C |
| Avg Low | 4.8°C | 5.2°C | 5.3°C | 5.8°C | 6.4°C | +1.6°C |
| Avg Rain | 164 mm | 157 mm | 147 mm | 184 mm | 178 mm | +14 mm |
May temperatures in Westport have risen by about 1.6°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -2.9°C (2013) to a record high of 19°C (2023).
Rainfall in May is a relatively wet time of year, averaging 165 mm, with a wettest year of 298 mm.
A good time to visit Westport
May is a good time to visit Westport, with days averaging 11.1°C and nights around 5.4°C (mean 8.3°C, cooler than Westport's yearly average) and higher rainfall. February and January 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 | 12.1°C | 9.5°C | 7.0°C | 15.0°C | 2.5°C | 179 mm | 93% | 0.4 m/s | 1.9 |
| 2024 | 9.8°C | 7.1°C | 4.4°C | 14.4°C | -1.1°C | 73 mm | 92% | 0.4 m/s | 1.9 |
| 2023 | 12.5°C | 10.3°C | 8.1°C | 19.0°C | 3.2°C | 259 mm | 95% | 0.4 m/s | 1.6 |
| 2022 | 12.5°C | 10.0°C | 7.5°C | 17.0°C | 2.0°C | 243 mm | 94% | 0.4 m/s | 1.8 |
| 2021 | 11.4°C | 8.5°C | 5.7°C | 16.0°C | -1.0°C | 183 mm | 91% | 0.4 m/s | 1.9 |
| 2020 | 11.7°C | 8.6°C | 5.6°C | 14.3°C | -0.6°C | 130 mm | 92% | 0.4 m/s | 1.8 |
| 2019 🔥 | 12.7°C | 10.3°C | 7.9°C | 16.6°C | 2.2°C | 208 mm | 93% | 0.4 m/s | 1.8 |
| 2018 | 10.7°C | 8.0°C | 5.3°C | 15.2°C | -1.8°C | 195 mm | 93% | 0.4 m/s | 1.9 |
| 2017 | 11.2°C | 8.1°C | 5.0°C | 14.2°C | -1.1°C | 163 mm | 92% | 0.4 m/s | 1.9 |
| 2016 | 11.8°C | 9.6°C | 7.5°C | 17.6°C | 1.3°C | 295 mm | 94% | 0.4 m/s | 1.6 |
| 2015 | 10.7°C | 8.1°C | 5.5°C | 15.1°C | -1.1°C | 187 mm | 93% | 0.4 m/s | 1.7 |
| 2014 | 11.3°C | 8.3°C | 5.4°C | 14.9°C | -1.8°C | 204 mm | 93% | 0.4 m/s | 1.9 |
| 2013 | 11.1°C | 8.1°C | 5.0°C | 15.7°C | -2.9°C | 123 mm | 91% | 0.4 m/s | 1.9 |
| 2012 | 10.8°C | 7.5°C | 4.1°C | 13.9°C | -0.9°C | 101 mm | 91% | 0.4 m/s | 2 |
| 2011 | 12.1°C | 9.9°C | 7.7°C | 16.7°C | 1.5°C | 244 mm | 93% | 0.4 m/s | 1.6 |
| 2010 | 10.9°C | 7.9°C | 5.0°C | 14.7°C | -0.7°C | 123 mm | 91% | 0.4 m/s | 1.8 |
| 2009 | 9.0°C | 5.7°C | 2.4°C | 12.9°C | -2.7°C | 123 mm | 88% | 0.5 m/s | 2.1 |
| 2008 | 10.7°C | 7.0°C | 3.3°C | 13.3°C | -1.4°C | 58 mm | 87% | 0.4 m/s | 2.1 |
| 2007 | 12.4°C | 9.8°C | 7.2°C | 15.2°C | 0.9°C | 135 mm | 92% | 0.4 m/s | 1.8 |
| 2006 | 11.3°C | 8.2°C | 5.1°C | 14.3°C | -1.6°C | 152 mm | 91% | 0.4 m/s | 2 |
| 2005 | 11.2°C | 8.5°C | 5.9°C | 16.4°C | 0.6°C | 127 mm | 92% | 0.4 m/s | 1.9 |
| 2004 | 11.4°C | 8.6°C | 5.7°C | 14.1°C | 1.3°C | 203 mm | 92% | 0.4 m/s | 1.9 |
| 2003 | 11.3°C | 8.6°C | 5.9°C | 14.6°C | 0.1°C | 227 mm | 93% | 0.4 m/s | 1.8 |
| 2002 | 10.7°C | 8.2°C | 5.8°C | 15.1°C | 0.9°C | 154 mm | 93% | 0.5 m/s | 1.7 |
| 2001 | 11.2°C | 8.1°C | 5.1°C | 16.3°C | -2.7°C | 114 mm | 91% | 0.4 m/s | 2 |
| 2000 | 11.2°C | 8.8°C | 6.5°C | 14.9°C | 2.7°C | 178 mm | 94% | 0.4 m/s | 1.8 |
| 1999 | 12.9°C | 9.7°C | 6.5°C | 15.6°C | -0.5°C | 81 mm | 89% | 0.4 m/s | 1.9 |
| 1998 | 11.4°C | 8.4°C | 5.4°C | 14.3°C | -0.9°C | 140 mm | 91% | 0.4 m/s | 1.7 |
| 1997 | 12.0°C | 9.2°C | 6.3°C | 16.6°C | 3.3°C | 97 mm | 92% | 0.4 m/s | 1.8 |
| 1996 | 10.5°C | 7.5°C | 4.5°C | 15.3°C | -1.3°C | 135 mm | 92% | 0.5 m/s | 1.8 |
| 1995 | 11.5°C | 8.4°C | 5.3°C | 15.9°C | -1.8°C | 193 mm | 91% | 0.5 m/s | 2 |
| 1994 🌧️ | 10.3°C | 7.8°C | 5.2°C | 13.9°C | -1.6°C | 298 mm | 93% | 0.5 m/s | 1.9 |
| 1993 | 10.6°C | 8.1°C | 5.6°C | 13.5°C | -0.3°C | 201 mm | 94% | 0.4 m/s | 1.8 |
| 1992 ❄️ | 8.7°C | 5.6°C | 2.5°C | 13.4°C | -2.6°C | 127 mm | 88% | 0.4 m/s | 1.9 |
| 1991 | 10.1°C | 7.7°C | 5.3°C | 13.0°C | 0.9°C | 98 mm | 93% | 0.4 m/s | 1.9 |
| 1990 | 10.4°C | 8.0°C | 5.7°C | 14.0°C | 1.2°C | 203 mm | 95% | 0.4 m/s | 1.8 |
| 1989 | 11.1°C | 8.3°C | 5.4°C | 16.7°C | -2.1°C | 138 mm | 90% | 0.4 m/s | 1.9 |
| 1988 | 10.1°C | 7.1°C | 4.0°C | 14.5°C | -1.3°C | 236 mm | 91% | 0.5 m/s | 1.8 |
| 1987 | 11.4°C | 8.6°C | 5.9°C | 14.6°C | 1.0°C | 224 mm | 92% | 0.4 m/s | 1.8 |
| 1986 | 10.8°C | 8.0°C | 5.1°C | 16.2°C | -1.7°C | 158 mm | 92% | 0.4 m/s | 1.9 |
| 1985 | 11.3°C | 8.1°C | 5.0°C | 14.8°C | 1.0°C | 86 mm | 89% | 0.4 m/s | 2.2 |
| 1984 | 9.9°C | 6.8°C | 3.8°C | 14.5°C | -2.6°C | 150 mm | 89% | 0.4 m/s | 1.8 |
| 1983 | 9.6°C | 6.9°C | 4.3°C | 13.9°C | -2.4°C | 147 mm | 90% | 0.5 m/s | — |
| 1982 | 10.7°C | 8.1°C | 5.5°C | 13.6°C | 2.2°C | 219 mm | 92% | 0.5 m/s | — |
| 1981 | 11.2°C | 7.7°C | 4.1°C | 16.2°C | -0.4°C | 114 mm | 89% | 0.5 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 11.1°C with lows near 5.4°C (mean 8.3°C), based on 45 years of NASA POWER data.
May averages 165 mm of rainfall in Westport, a relatively wet time of year. The wettest on record was 298 mm in 1994.
The hottest May reached 19°C in 2023. The coldest dipped to -2.9°C in 2013.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.6°C. Daytime highs moved from 10.5°C to 11.7°C and overnight lows from 4.5°C to 6.5°C over the same span.
May is one of the cooler months of the year in Westport and a relatively wet time of year, so plan for around 11.1°C daytime highs and 5.4°C at night.
Not quite — May is the 5th coolest month in Westport, averaging 8.3°C.
For May in Westport, pack warm layers and a jacket for chilly mornings, with typical highs of 11.1°C and lows of 5.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 92% — quite humid.
Average wind speed in May is 0.4 m/s. The windiest May on record averaged 0.5 m/s (1981).
The wettest May on record was 1994 with 298 mm. On average, May sees 165 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 Westport 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.
