Middle of the drier season · Weather & things to do
Big Island in September
Little changes in Big Island from August: highs stay near 56°F (14°C), lows near 43°F (6°C), and about 4.7 in (119 mm) of rain falls.
At 70/100 for comfort (3rd of 12), it's one of the best months to visit.
- Avg high
- 56°F (14°C)
- Avg low
- 43°F (6°C)
- Rain
- 4.7 in (119 mm)
- Humidity
- 82%
- Cloud cover
- 51%
- Daylight
- ~12 h 06 min
- Comfort score
- 70/100 · Good
What September feels like
Highs near 56°F (14°C) make for comfortable sightseeing weather.
Lows average 43°F (6°C).
Showers are part of the month, adding up to about 4.7 in (119 mm).
Plan around September
September is one of Big Island's best months on the climate data.
- Comfort holds steady from August (70 → 70/100).
- September sits inside the Apr – Oct window our Hawaii Paradise route recommends.
What to pack for September
- A warm layer for eveningsnights drop to 43°F
- Packable rain jacket or umbrellaa shower or two is likely
- Comfortable walking shoesmost places below are best reached on foot or with short walks
What to do in Big Island in September
With conditions on your side, the picks below favor time outside.
The Rim at Volcano House
Park lodge dining room with windows over Halemaʻumaʻu crater.
Why now September scores 70/100 for comfort, good conditions for being outside.
Punaluʻu Black Sand Beach
Jet-black sand beach where green sea turtles haul out to rest.
Why now Highs near 56°F and 4.7 in of monthly rain make this an easy outdoor pick.
Hawaiʻi Volcanoes National Park
Walk crater rims, steam vents and lava tubes around active Kīlauea.
Why now One to do outside while the weather is on your side.
Café 100
Hilo diner that has served loco moco since 1946.
Mauna Kea Visitor Information Station
Stargazing at 9,200 ft on one of the world's top observatory peaks.
Nearby in September
- Maui in September~97 mi · highs 73°F, 1.5 in rain · 9°C (17°F) warmer by day, drier
- Kailua & Lanikai in September~185 mi · highs 81°F, 1.4 in rain · 14°C (24°F) warmer by day, drier
- Waikiki in September~185 mi · highs 83°F, 2.0 in rain · 15°C (27°F) warmer by day, drier
- Oahu in September~200 mi · highs 81°F, 2.0 in rain · 14°C (25°F) warmer by day, drier
NASA POWER 2001–2025 monthly averages on a ~50 km grid, temperatures adjusted from the grid cell's ~1,145 m to Big Island's ~2,652 m elevation (standard lapse rate). Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Big Island in September: quick answers
Is September a good time to visit Big Island?
Yes. On the climate data it's one of the best months, scoring 70/100. Expect highs of 56°F (14°C) and 4.7 in (119 mm) of rain. September is inside the Apr – Oct window our Hawaii Paradise route recommends.
How cold is Big Island in September?
Average highs are 56°F (14°C) and average lows 43°F (6°C), making it the 3rd-warmest month by daytime highs.
Does it rain a lot in Big Island in September?
Some: about 4.7 in (119 mm) of rain falls across September on average, the 2nd-driest month of the year. The annual total is about 71.5 in (1816 mm).
What should I pack for Big Island in September?
Bring a warm layer for evenings (nights drop to 43°F), packable rain jacket or umbrella (a shower or two is likely) and comfortable walking shoes (most places below are best reached on foot or with short walks).
More on Big Island
Routes in season in September
- Hawaii Paradise Apr – Oct
Planning Big Island in September?
Bring the crew into one shared trip: vote on dates, build the day-by-day plan, split costs and share one packing list.