Water temperature in Grand Isle (LA) in July
Is it warm enough to swim in Grand Isle in July? Average water temperature in Grand Isle in July is 86.4°F and therefore suitable for comfortable swimming. The warmest sea in Grand Isle in July is 91.6°F, and the coldest is 82.2°F. Average high air temperature in Grand Isle in July is 90°F, and average low temperature is 76°F. To find out the sea temperature today and in the coming days, go to Current sea temperature in Grand Isle
Changes water temperature in Grand Isle in July 2025, 2024
To get an accurate forecast for the water temperature in Grand Isle for any chosen month, compare two years within a 10 year range using the chart below. In addition to the sea water temperature in Grand Isle, the selected years in the table also show the values of the maximum and minimum temperatures on each of the days of July.
You can choose any other years:
| Day | 2025 | 2024 | Min | Max |
|---|---|---|---|---|
| July 1 | 87.4°F | 88.9°F | 82.8°F | 89.8°F |
| July 2 | 86.2°F | 88.2°F | 83.1°F | 90.5°F |
| July 3 | 86.4°F | 89.2°F | 83.3°F | 89.6°F |
| July 4 | 86.4°F | 88.3°F | 83.3°F | 89.2°F |
| July 5 | 86.5°F | 88.7°F | 82.2°F | 88.7°F |
| July 6 | 88.9°F | 88.9°F | 82.4°F | 88.9°F |
| July 7 | 88.7°F | 88.7°F | 82.8°F | 89.6°F |
| July 8 | 88.3°F | 88.2°F | 82.6°F | 89.4°F |
| July 9 | 88.3°F | 88.2°F | 82.9°F | 89.1°F |
| July 10 | 88.2°F | 87.1°F | 83.3°F | 89.2°F |
| July 11 | 87.4°F | 86.5°F | 84°F | 88.9°F |
| July 12 | 88.5°F | 88°F | 84.2°F | 88.5°F |
| July 13 | 88.3°F | 89.6°F | 84.4°F | 89.6°F |
| July 14 | 89.2°F | 89.1°F | 84.9°F | 89.2°F |
| July 15 | 89.6°F | 88.3°F | 85.1°F | 89.6°F |
| Day | 2025 | 2024 | Min | Max |
|---|---|---|---|---|
| July 16 | 89.1°F | 89.2°F | 84.4°F | 89.2°F |
| July 17 | 88.7°F | 88.9°F | 84.6°F | 88.9°F |
| July 18 | 87.3°F | 85.6°F | 84.2°F | 88.3°F |
| July 19 | 87.6°F | 86.4°F | 83.5°F | 88.9°F |
| July 20 | 87.1°F | 86.4°F | 83.5°F | 90.1°F |
| July 21 | 88.9°F | 86°F | 83.7°F | 90.5°F |
| July 22 | 90.5°F | 87.3°F | 83.8°F | 90.5°F |
| July 23 | 90°F | 86.4°F | 84.2°F | 90°F |
| July 24 | 89.6°F | 86.4°F | 83.8°F | 89.6°F |
| July 25 | 88.9°F | 86.5°F | 84°F | 88.9°F |
| July 26 | 87.8°F | 86.2°F | 84.2°F | 89.1°F |
| July 27 | 88.5°F | 86.4°F | 84°F | 89.6°F |
| July 28 | 88.7°F | 87.1°F | 83.8°F | 90.3°F |
| July 29 | 89.2°F | 88.7°F | 84.4°F | 91.4°F |
| July 30 | 88.9°F | 88.5°F | 83.3°F | 90.5°F |
| July 31 | 89.2°F | 88.2°F | 84.7°F | 91.6°F |
Average water temperature in Grand Isle in July over a decade
| 2016 | 2017 | 2018 | 2019 | 2020 |
| 86.9°F | 85.3°F | 86°F | 86.5°F | 84.9°F |
| 2021 | 2022 | 2023 | 2024 | 2025 |
| 85.5°F | 87.8°F | 88.9°F | 87.8°F | 88.3°F |
Grand Isle sea state in July
Chart comparing the height of waves in Grand Isle in July over the past years. The red line indicates the height of the waves when swimming in the sea is prohibited. To view the current sea conditions, click on the graph.
Weather and climate in Grand Isle in July
This data display average monthly climate indicators in Grand Isle in July based on our historical weather readings over a period of ten years. In addition to temperature, we include data on the number of rainy and sunny days so you can have all the information about your destination before your trip
- Average HIGH temperature90°F
- Average LOW temperature76°F
- Average rainfall188mm/7.4''
Grand Isle water temperature during other months:
You can also view information about water temperature for other months by clicking on the month button below
