| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 43°F | 63°F | 52°F | 4.8" |
| February | 47°F | 65°F | 55°F | 7.2" |
| March | 53°F | 73°F | 62°F | 1.6" |
| April | 61°F | 80°F | 70°F | 11.3" |
| May | 68°F | 86°F | 77°F | 12.1" |
| June | 75°F | 91°F | 82°F | 7.7" |
| July | 75°F | 91°F | 82°F | 11.6" |
| August | 74°F | 92°F | 82°F | 7.1" |
| September | 70°F | 89°F | 78°F | 2.4" |
| October | 59°F | 82°F | 69°F | 3.7" |
| November | 50°F | 72°F | 60°F | 1.8" |
| December | 46°F | 66°F | 55°F | 3.2" |
| Index | Gueydan | Louisiana | National |
| Air quality index | 41 | 106 | 42 |
| Pollution index | 1,666,750 | 2,526,475 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 280 |
| Days with moderate air quality | 85 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.030% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Egan, LA | 1,031 | 41 | 18.0% |
| Estherwood, LA | 698 | 41 | 18.0% |
| Mermentau, LA | 637 | 41 | 18.0% |
| Morse, LA | 1,271 | 41 | 18.0% |
| Crowley, LA | 13,176 | 41 | 18.0% |
| Gueydan, LA | 1,232 | 41 | 18.0% |
| City | Population | Air Quality Index | National Avg. |
| Haven, KS | 1,232 | 40 | 20.0% |
| Harvard, NE | 1,232 | 19 | 62.0% |
| Lenape Heights, PA | 1,232 | 38 | 24.0% |
| Pinewood Estates, TX | 1,232 | 45 | 10.0% |
| Sycamore, GA | 1,231 | 40 | 20.0% |
| Gueydan, LA | 1,232 | 41 | 18.0% |