Hilo, HI Climate & Monthly Averages
Hilo has a tropical rainforest climate. August is the hottest month, averaging 80° by day; February is the coldest at 75°.
Rain, not cold, divides the year in Hilo
Temperature barely moves in Hilo - 3°C between the average August and the average February. Rainfall does the work instead: 9.9 inches (250 mm) in March against 5.1 inches (130 mm) in June.
The wet-and-dry rhythm at a glance
August is the warm end of the year, averaging 80°F (27°C) by day and 71°F (22°C) overnight. February is the coolest month, with highs of 75°F (24°C) and lows near 65°F (18°C). The gridded 2015-2024 daily record for this location tops out at 86°F (30°C) and bottoms at 58°F (14°C) - decade extremes, not all-time station records. Sunshine averages 10.1 hours a day over the year, peaking in June at 11.7 hours.
Precipitation concentrates in March - 9.9 inches (250 mm) on 23 days - and thins out by June. Days and nights are about 5°C apart on average - narrower than all but 4% of the 3496 cities in our dataset.
More climate facts for Hilo
- Hottest month: August - highs near 80°F (27°C)
- Coldest month: February - highs near 75°F (24°C)
- Decade extremes (2015-2024): 86°F (30°C) high · 58°F (14°C) low
- Wettest month: March (23 rainy days) · Sunniest: June (11.7 h sun/day)
- Climate type: tropical rainforest
- Annual swing: 3°C between the average warmest and coolest month · day to night: 5°C
- Average humidity: 82%
Choosing the right part of the year in Hilo
Choose dates by rain, not just temperature
Aim for January to June if you get the choice: warm days, manageable rainfall and plenty of daylight line up, and highs average 76°F (24°C) against roughly 22 wet days a month. For the same question asked the other way round, see where else is warm in January.
What the humidity changes
Pack for Hilo with proper waterproofs rather than an umbrella - wet days are the norm here. Even in August, lows of 71°F (22°C) make an extra layer worth the space.
Warm all year: the monthly rain pattern
Each card shows the average high and low. The bar places that month between Hilo's coldest night and warmest afternoon.
January
- Rain
- 15 days
- Sunshine
- 9.7 h
- Daylight
- 11.1 h
February
- Rain
- 20 days
- Sunshine
- 9.3 h
- Daylight
- 11.5 h
March
- Rain
- 23 days
- Sunshine
- 8.6 h
- Daylight
- 12.0 h
April
- Rain
- 24 days
- Sunshine
- 9.8 h
- Daylight
- 12.6 h
May
- Rain
- 26 days
- Sunshine
- 10.4 h
- Daylight
- 13.1 h
June
- Rain
- 23 days
- Sunshine
- 11.7 h
- Daylight
- 13.3 h
July
- Rain
- 27 days
- Sunshine
- 11.7 h
- Daylight
- 13.2 h
August
- Rain
- 26 days
- Sunshine
- 11.0 h
- Daylight
- 12.8 h
September
- Rain
- 24 days
- Sunshine
- 10.9 h
- Daylight
- 12.2 h
October
- Rain
- 22 days
- Sunshine
- 10.0 h
- Daylight
- 11.7 h
November
- Rain
- 22 days
- Sunshine
- 9.1 h
- Daylight
- 11.2 h
December
- Rain
- 22 days
- Sunshine
- 8.8 h
- Daylight
- 10.9 h
Looking for warmer alternatives? Browse warm places by month, or compare Hilo's coolest part of the year: February, March, January.
Monthly temperature and rain table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 76° | 65° | 15 | 5.7 in | 9.7 h/day | 11.1 h | 49% | 79% |
| February | 75° | 65° | 20 | 8.5 in | 9.3 h/day | 11.5 h | 69% | 80% |
| March | 75° | 66° | 23 | 9.9 in | 8.6 h/day | 12.0 h | 73% | 82% |
| April | 76° | 67° | 24 | 9.3 in | 9.8 h/day | 12.6 h | 81% | 82% |
| May | 77° | 68° | 26 | 8.0 in | 10.4 h/day | 13.1 h | 85% | 82% |
| June | 78° | 69° | 23 | 5.1 in | 11.7 h/day | 13.3 h | 77% | 82% |
| July | 80° | 70° | 27 | 6.6 in | 11.7 h/day | 13.2 h | 86% | 82% |
| August | 80° | 71° | 26 | 9.1 in | 11.0 h/day | 12.8 h | 83% | 83% |
| September | 80° | 71° | 24 | 5.5 in | 10.9 h/day | 12.2 h | 80% | 81% |
| October | 80° | 70° | 22 | 8.5 in | 10.0 h/day | 11.7 h | 69% | 81% |
| November | 78° | 68° | 22 | 9.4 in | 9.1 h/day | 11.2 h | 74% | 82% |
| December | 76° | 66° | 22 | 8.0 in | 8.8 h/day | 10.9 h | 70% | 82% |
How Hilo compares for rain and warmth
- Rain or snow reaches the ground on 273 days a year - more wet days than 97% of the 3496 cities we track.
- Annual precipitation is 93.6 inches (2378 mm) - wetter than 95% of the 3496 cities we track.
- Relative humidity averages 82% - more humid than 92% of the 3496 cities we track.
These comparisons use the same ten-year window for every city in the dataset.
How the calendar changes in warm-weather Hilo
March through May
March through May in Hilo is mild and warm, with daytime highs averaging 76°F (24°C) and nights around 67°F (19°C); rain falls on around 74 of the 90 days.
June through August
June through August brings comfortable warmth here - highs near 79°F (26°C), nights near 70°F (21°C), and rain falls on around 76 of the 90 days. Daylight is generous - around 11.5 hours of sun a day.
September through November
Through September through November, Hilo brings comfortable warmth: 79°F (26°C) by day, 70°F (21°C) after dark, and rain falls on around 68 of the 90 days. Daylight is generous - around 10.0 hours of sun a day.
December through February
December through February in Hilo settles into easy warmth, with daytime highs averaging 75°F (24°C) and nights around 65°F (18°C); rain falls on around 56 of the 90 days.
Questions about heat and rain in Hilo
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How much does the weather change through the year in Hilo?
Hilo temperature extremes in the 2015–2024 dataset
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need another precipitation unit? Use the rainfall converter.