Haleakala National Park weather in May
May in Haleakala National Park: cool, a little rain, with clean air — one of the best months to visit.
#2 of 12 months in Haleakala National Park · #133 of 604 destinations to visit in May · comfort 88/100 (tier A)
Updated June 2026 · climate normals from ERA5 reanalysis
Haleakala National Park climate normals — May
| Daytime high | 15°C / 59°F | 🙂 cool |
|---|---|---|
| Nighttime low | 11°C / 52°F | |
| Feels like (high) | 13°C / 55°F | |
| Rainfall | 70 mm / 2.8 in | 🌦 some rain |
| Rainy days | 21 days | |
| Humidity | 77% | 💦 very humid |
| Dew point | 9°C / 48°F | |
| Sunshine | 11.7 h/day | |
| Daylight | 13.1 h | |
| Wind | 23 km/h / 14 mph | |
| Air quality (US AQI) | 43 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Where is Haleakala National Park?
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Haleakala National Park in May — FAQ
- Is May a good time to visit Haleakala National Park?
- May in Haleakala National Park: cool, a little rain, with clean air — one of the best months to visit. It ranks #2 of 12 months for Haleakala National Park on SeasonMap's comfort score (88/100).
- What is the weather like in Haleakala National Park in May?
- In May, Haleakala National Park averages a daily high of 15.1°C and a low of 11.3°C, with about 70.1 mm of rain over roughly 20.8 rainy days.
- What is the air quality in Haleakala National Park in May?
- Haleakala National Park has a mean US Air Quality Index of about 43 in May.