Hilo, Hawaii weather in May
Temperature, sea and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Good
Best time to visit: January – December
What is the weather like in Hilo, Hawaii in May?
In May, Hilo, Hawaii is warm: daytime highs average 25 °C, and even at night it stays warm at around 20 °C. The sea averages 24.9 °C – pleasant for swimming. The sun shines for around 8 hours a day. It is the rainy season: rain falls on about 22 days, totalling 108 mm. The air is often humid and muggy. All in all, May is a good month for a holiday in Hilo, Hawaii.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 13 h 3 min05:45 – 18:48
- UV index
- 12 · extremeclear sky, noon (estimate)All months
- Muggy days
- 22 daysdew point 18 °C or moreAll months
- Wind
- 17 km/haverage daily peakAll months
- Cloud cover
- 62 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC−10Pacific/Honolulu
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %83 %
- Few rainy daysweight 30 %0 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Nature escape”.
What to pack in May
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Insect repellent
- Rain jacket or umbrella
Hilo, Hawaii in May: quick answers
Is Hilo, Hawaii hot in May?
Warm rather than hot: in May, daytime highs in Hilo, Hawaii average 25 °C and nights cool to about 20 °C.
Can you swim in Hilo, Hawaii in May?
Yes. In May the sea averages 24.9 °C – pleasant for swimming.
Does it rain much in Hilo, Hawaii in May?
It rains often – on about 22 days, adding up to 108 mm.
Hilo, Hawaii month by month
The whole year in Hilo, HawaiiAll destinations: USAHawaii weather in MayWhere to go in MaySea temperature in May
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences