July is one of the warmer months of the year in Hilo, with average highs near 24.6°C and lows around 20.6°C (mean 22.6°C). It is one of the drier months, averaging 124 mm of rainfall and 82% relative humidity across the period.
July is one of the warmer months of the year in Hilo. Across 45 years of records, the warmest July in Hilo was 2015 — when the month averaged 23.7°C — while the coldest were 2010, 2011 and 2012 at 21.5°C. Typical July days reach 24.6°C with nights near 20.6°C. The long-term July temperature trend is broadly flat.
July is one of the drier months in Hilo, averaging 124 mm of rainfall. The wettest July on record was 1985 with 584 mm, while the driest was 1995 at 4 mm.
Relative humidity in Hilo during July averages 82%. The most humid July was 2018 at 86%, and the least humid was 1996 at 76%.
July receives about 6.1 kWh/m²/day of solar energy in Hilo. The sunniest Julys were 2017 and 2023 at 6.8 kWh/m²/day, and the cloudiest was 1989 at 5.5.
Average wind speed in Hilo during July is 4.3 m/s. The windiest July was 1989 at 4.9 m/s, while the calmest was 2015 at 3.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.4°C | 22.9°C | 22.3°C | 22.6°C | 22.7°C | +0.3°C |
| Avg High | 24.4°C | 25.1°C | 24.3°C | 24.6°C | 24.8°C | +0.4°C |
| Avg Low | 20.5°C | 20.6°C | 20.4°C | 20.7°C | 20.7°C | +0.2°C |
| Avg Rain | 217 mm | 25 mm | 196 mm | 110 mm | 49 mm | -168 mm |
July temperatures in Hilo have risen by about 0.4°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 18.1°C (1999) to a record high of 28.2°C (2000).
Rainfall in July is one of the drier months, averaging 124 mm, with a wettest year of 584 mm.
One of the best times to visit Hilo
July is one of the best times to visit Hilo. Expect days averaging 24.6°C and nights around 20.6°C (mean 22.6°C) — close to Hilo's yearly average — with higher rainfall (124 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 25.1°C | 22.9°C | 20.7°C | 26.8°C | 19.8°C | 57 mm | 81% | 4 m/s | 6.6 |
| 2024 | 24.6°C | 22.6°C | 20.6°C | 25.7°C | 19.9°C | 39 mm | 82% | 4.3 m/s | 6.7 |
| 2023 | 24.6°C | 22.6°C | 20.7°C | 25.4°C | 19.7°C | 37 mm | 83% | 4.1 m/s | 6.8 |
| 2022 | 24.6°C | 22.7°C | 20.7°C | 25.7°C | 19.8°C | 43 mm | 82% | 4.6 m/s | 6.5 |
| 2021 | 24.7°C | 22.7°C | 20.7°C | 25.7°C | 19.8°C | 54 mm | 83% | 4.3 m/s | 6.2 |
| 2020 | 25.0°C | 22.9°C | 20.9°C | 26.6°C | 20.3°C | 62 mm | 82% | 4.1 m/s | 6.4 |
| 2019 | 25.4°C | 23.4°C | 21.4°C | 26.4°C | 20.5°C | 78 mm | 83% | 3.9 m/s | 6.3 |
| 2018 | 25.0°C | 23.2°C | 21.4°C | 25.9°C | 20.2°C | 71 mm | 86% | 4.1 m/s | 5.8 |
| 2017 | 25.0°C | 23.0°C | 21.0°C | 26.3°C | 19.5°C | 53 mm | 84% | 3.8 m/s | 6.8 |
| 2016 | 25.0°C | 23.2°C | 21.3°C | 26.9°C | 20.3°C | 248 mm | 85% | 4 m/s | 6.1 |
| 2015 🔥 | 25.7°C | 23.7°C | 21.7°C | 27.7°C | 20.4°C | 105 mm | 84% | 3.7 m/s | 5.9 |
| 2014 | 24.7°C | 22.8°C | 21.0°C | 25.6°C | 20.1°C | 165 mm | 85% | 4 m/s | 5.9 |
| 2013 | 24.5°C | 22.5°C | 20.5°C | 26.9°C | 19.6°C | 80 mm | 82% | 4.1 m/s | 6 |
| 2012 | 23.4°C | 21.5°C | 19.7°C | 24.5°C | 18.9°C | 114 mm | 83% | 4.5 m/s | 6.7 |
| 2011 | 23.4°C | 21.5°C | 19.6°C | 24.9°C | 18.5°C | 75 mm | 83% | 4.2 m/s | 6.2 |
| 2010 ❄️ | 23.4°C | 21.5°C | 19.7°C | 24.4°C | 18.8°C | 117 mm | 83% | 4.1 m/s | 6.3 |
| 2009 | 24.1°C | 22.3°C | 20.6°C | 25.9°C | 19.2°C | 322 mm | 85% | 4.3 m/s | 5.9 |
| 2008 | 24.3°C | 22.3°C | 20.3°C | 25.7°C | 19.3°C | 135 mm | 83% | 3.9 m/s | 5.8 |
| 2007 | 24.1°C | 22.1°C | 20.2°C | 25.0°C | 18.9°C | 194 mm | 83% | 4.1 m/s | 6.5 |
| 2006 | 24.2°C | 22.3°C | 20.4°C | 25.5°C | 19.6°C | 227 mm | 83% | 4.4 m/s | 6.5 |
| 2005 | 24.0°C | 22.3°C | 20.6°C | 24.6°C | 19.5°C | 241 mm | 84% | 4.6 m/s | 6.3 |
| 2004 | 24.3°C | 22.4°C | 20.4°C | 25.5°C | 19.9°C | 146 mm | 82% | 4.1 m/s | 6.3 |
| 2003 | 24.2°C | 22.4°C | 20.6°C | 25.5°C | 19.5°C | 188 mm | 84% | 4.3 m/s | 6.1 |
| 2002 | 24.0°C | 22.1°C | 20.3°C | 25.6°C | 19.3°C | 388 mm | 85% | 4.3 m/s | 6.1 |
| 2001 | 24.8°C | 22.6°C | 20.3°C | 25.6°C | 19.6°C | 39 mm | 79% | 4.3 m/s | 6.2 |
| 2000 | 24.7°C | 22.6°C | 20.6°C | 28.2°C | 19.5°C | 83 mm | 81% | 4.7 m/s | 6 |
| 1999 | 24.0°C | 21.7°C | 19.4°C | 24.9°C | 18.1°C | 18 mm | 77% | 4.5 m/s | 6.6 |
| 1998 | 24.3°C | 22.0°C | 19.8°C | 25.9°C | 19.2°C | 32 mm | 77% | 4.7 m/s | 6.3 |
| 1997 | 25.9°C | 23.5°C | 21.2°C | 27.4°C | 20.2°C | 39 mm | 77% | 4.7 m/s | 6 |
| 1996 | 25.7°C | 23.4°C | 21.1°C | 27.7°C | 20.2°C | 5 mm | 76% | 4.7 m/s | 6 |
| 1995 | 25.7°C | 23.4°C | 21.0°C | 26.8°C | 19.6°C | 4 mm | 77% | 4.8 m/s | 6.1 |
| 1994 | 25.7°C | 23.4°C | 21.1°C | 26.7°C | 20.2°C | 16 mm | 80% | 4.5 m/s | 6 |
| 1993 | 25.4°C | 23.2°C | 21.0°C | 26.7°C | 19.9°C | 14 mm | 79% | 4.6 m/s | 5.7 |
| 1992 | 25.8°C | 23.5°C | 21.2°C | 27.2°C | 20.0°C | 6 mm | 77% | 4.5 m/s | 5.7 |
| 1991 | 24.3°C | 22.2°C | 20.2°C | 25.3°C | 18.6°C | 71 mm | 81% | 4.1 m/s | 5.7 |
| 1990 | 24.2°C | 22.2°C | 20.1°C | 25.7°C | 18.5°C | 41 mm | 83% | 4.2 m/s | 5.6 |
| 1989 | 24.4°C | 22.6°C | 20.8°C | 25.6°C | 19.7°C | 100 mm | 82% | 4.9 m/s | 5.5 |
| 1988 | 24.5°C | 22.4°C | 20.4°C | 25.5°C | 19.4°C | 9 mm | 79% | 4.5 m/s | 6 |
| 1987 | 24.5°C | 22.6°C | 20.7°C | 25.6°C | 19.5°C | 178 mm | 84% | 4.2 m/s | 5.9 |
| 1986 | 24.7°C | 22.9°C | 21.2°C | 26.0°C | 20.5°C | 53 mm | 85% | 4.4 m/s | 5.7 |
| 1985 🌧️ | 23.9°C | 22.1°C | 20.2°C | 25.2°C | 19.5°C | 584 mm | 83% | 4 m/s | 6 |
| 1984 | 24.1°C | 22.0°C | 19.9°C | 25.2°C | 18.6°C | 56 mm | 82% | 3.8 m/s | 5.8 |
| 1983 | 23.5°C | 21.7°C | 20.0°C | 24.1°C | 19.0°C | 371 mm | 84% | 4.7 m/s | — |
| 1982 | 24.8°C | 23.0°C | 21.1°C | 26.9°C | 20.2°C | 570 mm | 84% | 4.2 m/s | — |
| 1981 | 25.0°C | 22.6°C | 20.2°C | 26.0°C | 19.2°C | 33 mm | 78% | 4 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 24.6°C with lows near 20.6°C (mean 22.6°C), based on 45 years of NASA POWER data.
July averages 124 mm of rainfall in Hilo, one of the drier months. The wettest on record was 584 mm in 1985.
The hottest July reached 28.2°C in 2000. The coldest dipped to 18.1°C in 1999.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 0.4°C. Daytime highs moved from 24.3°C to 24.7°C and overnight lows from 20.3°C to 20.7°C over the same span.
July is one of the warmer months of the year in Hilo and one of the drier months, so plan for around 24.6°C daytime highs and 20.6°C at night.
Not quite — July is the 9th coolest month in Hilo, averaging 22.6°C.
For July in Hilo, pack light layers you can adjust through the day, with typical highs of 24.6°C and lows of 20.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 82% — quite humid.
Average wind speed in July is 4.3 m/s. The windiest July on record averaged 4.9 m/s (1989).
The wettest July on record was 1985 with 584 mm. On average, July sees 124 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Hilo behaves each July, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for July specifically, along with year-by-year records and how the month has changed over the decades.
