Weather in Kauai: September
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Average day temperature: | 80.3°F |
| Average night temperature: | 76.1°F | |
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Sea water temperature: | 80.6°F |
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Number of sunny days: | 2 days |
| Day length: | 11.9 - 12.6 hours | |
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Number of rainy days: | 0 days |
| Precipitation totals: | 0.6 in. | |
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forecast
| Kauai |
temperature
| Kauai |
Air temperature in September, °F
The highest day temperature during September of 2025 was 82°F. At the same time the lowest night temperature was 73°F. Daily and nightly averages during September were 81.0°F and 75.1°F.
Sea water temperature in Kauai in September, °F
The average sea water temperature in September of 2025 was 81.5°F. The highest and lowest sea temperatures during the month were 81.9°F and 81.1°F.
Mostly all days in September are cloudy but sunny and partly cloudy days are also possible.
Precipitation total in September, in.
Precipitation total value in Kauai in September is 0.6 in. Other months of the year show relatively similar values.
The average wind speed value in September is 10.1 mph It makes September one of the least windy months of the year.
This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 5.3.
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Kauai on a weather map
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