| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 38°F | 59°F | 47°F | 5.0" |
| February | 41°F | 62°F | 50°F | 4.1" |
| March | 48°F | 71°F | 59°F | 5.9" |
| April | 56°F | 79°F | 66°F | 6.0" |
| May | 63°F | 85°F | 73°F | 4.7" |
| June | 71°F | 92°F | 81°F | 3.8" |
| July | 73°F | 94°F | 82°F | 3.9" |
| August | 73°F | 95°F | 82°F | 4.3" |
| September | 67°F | 90°F | 77°F | 4.2" |
| October | 54°F | 80°F | 66°F | 5.4" |
| November | 46°F | 69°F | 56°F | 4.1" |
| December | 40°F | 61°F | 49°F | 5.5" |
| Index | Start | Louisiana | National |
| Air quality index | 34 | 106 | 42 |
| Pollution index | 583,418 | 2,526,475 | 2,726,193 |
| Measurement | Total |
| Days measured | 363 |
| Days with good air quality | 335 |
| Days with moderate air quality | 28 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Sterlington, LA | 2,814 | 34 | 32.0% |
| Rayville, LA | 3,635 | 34 | 32.0% |
| Lakeshore, LA | 2,859 | 34 | 32.0% |
| Collinston, LA | 178 | 34 | 32.0% |
| Swartz, LA | 5,284 | 34 | 32.0% |
| Start, LA | 996 | 34 | 32.0% |
| City | Population | Air Quality Index | National Avg. |
| Eldridge, CA | 996 | 35 | 30.0% |
| Buffalo Center, IA | 996 | 15 | 70.0% |
| Funkstown, MD | 996 | 40 | 20.0% |
| Dollar Bay, MI | 996 | 8 | 84.0% |
| Aulander, NC | 996 | 36 | 28.0% |
| Start, LA | 996 | 34 | 32.0% |