| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 46°F | 65°F | 54°F | 11.3" |
| February | 48°F | 67°F | 57°F | 5.8" |
| March | 54°F | 74°F | 64°F | 7.3" |
| April | 60°F | 79°F | 70°F | 11.7" |
| May | 66°F | 85°F | 75°F | 17.5" |
| June | 72°F | 90°F | 81°F | 8.4" |
| July | 74°F | 91°F | 81°F | 8.4" |
| August | 74°F | 90°F | 81°F | 12.8" |
| September | 71°F | 88°F | 79°F | 10.6" |
| October | 61°F | 81°F | 71°F | 10.7" |
| November | 52°F | 73°F | 61°F | 11.5" |
| December | 49°F | 67°F | 57°F | 9.8" |
| Index | Grand Isle | Louisiana | National |
| Air quality index | 41 | 106 | 42 |
| Pollution index | 3,881,730 | 2,526,475 | 2,726,193 |
| Measurement | Total |
| Days measured | 361 |
| Days with good air quality | 272 |
| Days with moderate air quality | 87 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.040% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Grand Isle, LA | 690 | 41 | 18.0% |
| City | Population | Air Quality Index | National Avg. |
| Fontanelle, IA | 690 | 39 | 22.0% |
| Paris, ID | 690 | 44 | 12.0% |
| Ozawkie, KS | 690 | 41 | 18.0% |
| Woodland Hills, KY | 690 | 49 | 2.0% |
| Argyle, MN | 690 | 33 | 34.0% |
| Grand Isle, LA | 690 | 41 | 18.0% |