| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 39°F | 61°F | 48°F | 9.4" |
| February | 41°F | 64°F | 51°F | 7.9" |
| March | 49°F | 73°F | 60°F | 13.5" |
| April | 56°F | 80°F | 67°F | 7.9" |
| May | 63°F | 86°F | 73°F | 10.8" |
| June | 71°F | 93°F | 81°F | 7.9" |
| July | 72°F | 94°F | 82°F | 3.8" |
| August | 73°F | 96°F | 82°F | 6.9" |
| September | 67°F | 91°F | 77°F | 6.3" |
| October | 55°F | 82°F | 66°F | 8.0" |
| November | 46°F | 71°F | 57°F | 6.3" |
| December | 41°F | 62°F | 50°F | 7.5" |
| Index | Calvin | Louisiana | National |
| Air quality index | 30 | 106 | 42 |
| Pollution index | 2,517,590 | 2,526,475 | 2,726,193 |
| Measurement | Total |
| Days measured | 119 |
| Days with good air quality | 107 |
| Days with moderate air quality | 12 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.070% |
| Lead | 0.010% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Goldonna, LA | 436 | 30 | 40.0% |
| Joyce, LA | 113 | 30 | 40.0% |
| St. Maurice, LA | 383 | 30 | 40.0% |
| Winnfield, LA | 4,586 | 30 | 40.0% |
| Clarence, LA | 339 | 30 | 40.0% |
| Calvin, LA | 232 | 30 | 40.0% |
| City | Population | Air Quality Index | National Avg. |
| Alta Vista, IA | 232 | 15 | 70.0% |
| Maysville, IA | 232 | 46 | 8.0% |
| Volga, IA | 232 | 39 | 22.0% |
| Rockford, ID | 232 | 27 | 46.0% |
| Thawville, IL | 232 | 42 | 16.0% |
| Calvin, LA | 232 | 30 | 40.0% |