Hilo, Big Island weather in May 2025

Expect daytime maximum temperatures of 23°C in Hilo, Big Island in May based on long-term weather averages. There are 5 hours of sunshine per day on average with 14 days with some rainfall and typically 206 mm of rainfall in the month.

  • 23°C maximum daytime temperature in May in Hilo, Big Island23
    23°C max day temperature
  • 5 hours of sunshine per day
  • 14 days with some rainfall in May in Hilo, Big Island14
    14 days with some rainfall
  • 15°C minimum night-time temperature in May in Hilo, Big Island15
    15°C min night temperature
  • 13 hours of daylight per day in May in Hilo, Big Island13
    13 hours of daylight per day
  • Moderate heat & humidity in May in Hilo, Big IslandM
    Moderate heat & humidity
  • 206 mm monthly rainfall in May in Hilo, Big Island206
    206 mm of monthly rainfall
  • UV (maximum) index 11+ (Extreme) in May in Hilo, Big Island11
    11+ (Extreme) UV index
  • 25°C sea temperature in May in Hilo, Big Island25
    25°C sea temperature

More about Hilo, Big Island

Hilo, Big Island by month

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The May weather guide for Hawaii (Hilo, Big Island) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm)  |  Imperial (°F / inches)

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More about the USA

How hot is it in Hilo, Big Island in May?

Daytime temperatures usually reach 23°C in Hilo, Big Island in May, falling to 15°C at night.

How sunny is it in Hilo, Big Island in May?

There are normally 5 hours of bright sunshine each day in Hilo, Big Island in May - that's 37% of daylight hours.

How warm is the sea around Hilo, Big Island in May?

The average sea temperature around Hilo, Big Island in May is 25°C.

Does it rain in Hilo, Big Island in May?

There are usually 14 days with some rain in Hilo, Big Island in May and the average monthly rainfall is 206mm.

Hilo, Big Island May sunrise & sunset times

Browse the sunrise and sunset times for Hilo, Big Island in May 2025. Select a month to view Hilo, Big Island sunrise and sunset times for the next 12 months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Thursday, 1st May 2025 05:51 18:44
Friday, 16th May 2025 05:44 18:50
Saturday, 31st May 2025 05:41 18:56

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