September weather forecastWaimea Canyon State Park, HI
September
Weather in September
September signals a gradual transition towards autumn accompanied by falling daylight hours and increased sea temperatures. In this month, the highest sea temperature of 80.5°F (26.9°C) is noted, at the tail end of the summer. A decrease in daylight marks this transition, with an average of 12.3 hours noted. The weather progression towards cooler climes and shorter days will continue into the next month. However, September's weather stays steady, not displaying strikingly unique or erratic weather conditions.Ocean temperature
With an average ocean temperature of 80.4°F (26.9°C), September is the month with the warmest seawater.Note: For swimming, diving, or other water activities, the temperature range of 77°F (25°C) to 84.2°F (29°C) is perceived as exceptionally enjoyable and comfortable even for prolonged periods.
Daylight
In September, the average length of the day is 12h and 16min.On the first day of September, sunrise is at 6:21 am and sunset at 6:54 pm. On the last day of the month, sunrise is at 6:30 am and sunset at 6:26 pm HST.
Updated: Aug 30, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
September is the month with the warmest seawater, with an average ocean temperature of 80.4°F (26.9°C).
In Waimea Canyon State Park, Hawaii, in September, the average water temperature is 80.4°F (26.9°C). Water temperature between 77°F (25°C) and 84.2°F (29°C) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.
The average day length in September is 12h and 16min.
In September, on the first day of the month, sunrise is at 6:21 am and sunset at 6:54 pm. On the last day of the month, sunrise is at 6:30 am and sunset at 6:26 pm HST.
Average sea temperature in September
Waimea Canyon State Park, HI
- Average sea temperature in September: 80.5°F
The best month for swimming (with the highest average sea temperature) is September (80.5°F).
The coldest month (with the lowest average sea temperature) is March (75.4°F).
Average daylight in September
Waimea Canyon State Park, HI
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 30min).
The month with the shortest days is December (Average daylight: 10h and 48min).





