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.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Hilo's climate page.
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%
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 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
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tolerable
unpleasant
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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.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Hilo's climate page.
Temperature Rainfall Sunshine Humidity
See the full Hilo climate overview or explore weather in the United States of America.
