End of the drier season · Weather & things to do
Oahu in September
Oahu's warmest month brings highs averaging 81°F (27°C), lows of 76°F (24°C) and about 2.0 in (50 mm) of rain.
At 91/100 for comfort (5th of 12), it's one of the best months to visit.
- Avg high
- 81°F (27°C)
- Avg low
- 76°F (24°C)
- Rain
- 2.0 in (50 mm)
- Humidity
- 74%
- Cloud cover
- 42%
- Daylight
- ~12 h 07 min
- Comfort score
- 91/100 · Great
What September feels like
Warm afternoons near 81°F (27°C) make long days outdoors easy.
Nights stay warm too, with lows averaging 76°F (24°C).
About 2.0 in (50 mm) of rain falls in a typical year's September.
It's breezy, with average winds near 12 mph (5.5 m/s) at ground level.
Plan around September
September is one of Oahu's best months on the climate data.
- Last of the best-scoring months: by October, the score drops to 85/100.
- Comfort holds steady from August (91 → 91/100).
- September sits inside the Apr – Oct window our Hawaii Paradise route recommends.
What to pack for September
- Light, breathable clothes81°F afternoons
- Sunscreen, sunglasses and a hatstrong sun this month
- Windproof shellaverage wind 12 mph
- Comfortable walking shoesmost places below are best reached on foot or with short walks
What to do in Oahu in September
September is good outdoor weather here, so these picks lean toward the open air.
Waikiki Beach
Calm, sandy swim and beginner surf with Diamond Head as the backdrop.
Why now September scores 91/100 for comfort, good conditions for being outside.
Pearl Harbor National Memorial
Boat out to the USS Arizona Memorial and walk the museums on the 1941 attack.
Why now Highs near 81°F and 2.0 in of monthly rain make this an easy outdoor pick.
Helena's Hawaiian Food
James Beard–honored family spot for kalua pig, pipikaula short ribs and lau lau.
Matsumoto Shave Ice
Haleiwa shave ice stand open since 1951, a North Shore ritual.
Hanauma Bay Nature Preserve
Protected volcanic bay with reef snorkeling and green sea turtles.
Why now One to do outside while the weather is on your side.
Nearby in September
- Waikiki in September~15 mi · highs 83°F, 2.0 in rain · 1°C (2°F) warmer by day, about as wet
- Kailua & Lanikai in September~18 mi · highs 81°F, 1.4 in rain · similar daytime temperatures, about as wet
- Maui in September~116 mi · highs 73°F, 1.5 in rain · 5°C (8°F) cooler by day, about as wet
- Big Island in September~200 mi · highs 56°F, 4.7 in rain · 14°C (25°F) cooler by day, wetter
NASA POWER 2001–2025 monthly averages on a ~50 km grid. Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Oahu in September: quick answers
Is September a good time to visit Oahu?
Yes. On the climate data it's one of the best months, scoring 91/100. Expect highs of 81°F (27°C) and 2.0 in (50 mm) of rain. September is inside the Apr – Oct window our Hawaii Paradise route recommends.
How hot is Oahu in September?
Average highs are 81°F (27°C) and average lows 76°F (24°C), making it the warmest month by daytime highs.
Does it rain a lot in Oahu in September?
Not much: about 2.0 in (50 mm) of rain falls across September on average, the 5th-driest month of the year. The annual total is about 30.4 in (771 mm).
What should I pack for Oahu in September?
Bring light, breathable clothes (81°F afternoons), sunscreen, sunglasses and a hat (strong sun this month), windproof shell (average wind 12 mph) and comfortable walking shoes (most places below are best reached on foot or with short walks).
Routes in season in September
- Hawaii Paradise Apr – Oct
Planning Oahu in September?
Plan it together in TripsCircle: one itinerary, one shared packing list and costs split as you go.