Weather in Grand Isle: August
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Average day temperature: | 85.8°F |
| Average night temperature: | 83.4°F | |
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Sea water temperature: | 88.0°F |
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Number of sunny days: | 10 days |
| Day length: | 12.8 - 13.5 hours | |
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Number of rainy days: | 4 days |
| Precipitation totals: | 2.4 in. | |
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forecast
| Grand Isle |
temperature
| Grand Isle |
Air temperature in August, °F
The highest day temperature during August of 2025 was 87°F. At the same time the lowest night temperature was 81°F. Daily and nightly averages during August were 85.1°F and 83.4°F.
Sea water temperature in Grand Isle in August, °F
The average sea water temperature in August of 2025 was 87.9°F. The highest and lowest sea temperatures during the month were 90.1°F and 86.0°F.
Mostly all days in August are partly cloudy but sunny or cloudy days are also possible.
Precipitation total in August, in.
Precipitation total value in Grand Isle in August is 2.4 in. Other months of the year show relatively similar values.
The average wind speed value in August is 9.2 mph It makes August 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 August is: 7.6.
Best time for vacation in Grand Isle
Grand Isle on a weather map
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