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Hilo Weather in May

May in Hilo sees daytime temperatures around 24°C (75°F) and lows of 18°C (64°F) at night. Being part of the rainy season, heavy rainfall is a regular part of the day, so pack accordingly.

Rainfall in Hilo in May

Hilo is in the rainy season in May, with rain on around 19 days and an average of 171 mm (6.7 in). Rainy season showers tend to be fairly substantial. A good rain jacket or umbrella is worth having with you most days.

Temperature in Hilo in May

May in Hilo brings typical temperatures with highs around 24°C (75°F) and lows of 18°C (64°F). Overall, the month follows a fairly predictable daily temperature pattern. Nights cool down to 18°C (64°F), so a light jacket or extra layer is useful once the sun goes down. On the plus side, the cooler nights make for comfortable sleeping conditions.

Sunshine in Hilo in May

The city usually sees around 158 hours of sunlight, indicating a moderately sunny period (despite it being part of rainy season).

If you're a fan of comfortable temperatures and drier conditions, May is a great time to visit.

Hilo Temperature in May

Min Temperature
18°C (64°F)
Max Temperature
24°C (75°F)
Chance of Rain
63%
Precipitation
171 mm (6.7 in)
Rainy days
19 days
Humidity
78%
Sunshine
158 hours
Percentage Sunshine
37%

Hilo Weather by Month

Pick a month to see the average temperature, rainfall and sunshine in Hilo - and find the best time to visit.

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Hilo typically stay consistent throughout May, with daily highs averaging around 24°C (75°F). Nights are pleasant, with lows around 20°C (68°F).

Average temperatures in May

Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in May

Historical weather records for Hilo in May

Browse day-by-day weather records for Hilo spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Hilo historical weather extremes in May

According to our 50 years of weather records for Hilo, the following extremes were recorded between 1976 and 2026.

  • Hilo recorded its highest May temperature of 33°C (91°F) on May 15, 2021.
  • The coldest May day was on May 6, 2006, with a maximum of 22°C (72°F).
  • Hilo registered its coldest May night on May 8, 1992, with temperatures dropping to 15°C (59°F).

Best Places in the United States of America in May

Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in May →

perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

What to Wear in Hilo in May

Pleasant temperatures in May mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Heavy rain is guaranteed, please bring a good poncho and waterproof everything! It won't hurt to bring your sunglasses along, as you'll see some sunny periods.

What To Do in Hilo in May

We rated the following activities from 1 (least suitable) to 10 (best) to do.

  • Swimming
    7/10
  • Camping
    6/10

Hilo 3-Day Forecast

Popular in May

Where to go in May - average daytime high across popular destinations.

Bucket list

Need travel inspiration? Check out our bucket list articles and be inspired.