| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 42°F | 61°F | 50°F | 8.4" |
| February | 43°F | 63°F | 51°F | 6.7" |
| March | 49°F | 72°F | 59°F | 6.7" |
| April | 53°F | 76°F | 63°F | 6.5" |
| May | 61°F | 84°F | 71°F | 12.5" |
| June | 69°F | 89°F | 78°F | 5.2" |
| July | 72°F | 90°F | 79°F | 6.5" |
| August | 72°F | 94°F | 82°F | 13.0" |
| September | 70°F | 88°F | 77°F | 8.9" |
| October | 55°F | 78°F | 65°F | 1.2" |
| November | 48°F | 72°F | 57°F | 7.0" |
| December | 42°F | 64°F | 51°F | 3.3" |
| Index | Morgantown | Mississippi | National |
| Air quality index | 30 | 40 | 42 |
| Pollution index | 2,084,210 | 1,514,109 | 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 | 0.000% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Cloverdale, MS | 640 | 30 | 40.0% |
| Ferriday, LA | 3,328 | 30 | 40.0% |
| Natchez, MS | 15,207 | 30 | 40.0% |
| Minorca, LA | 1,774 | 30 | 40.0% |
| Ridgecrest, LA | 696 | 30 | 40.0% |
| Morgantown, MS | 1,860 | 30 | 40.0% |
| City | Population | Air Quality Index | National Avg. |
| Navajo, NM | 1,860 | 17 | 66.0% |
| Shamokin Dam, PA | 1,860 | 35 | 30.0% |
| Great Falls, SC | 1,860 | 43 | 14.0% |
| Westwood Shores, TX | 1,860 | 52 | 4.0% |
| Whitehead, MB | 1,860 | n/a | |
| Morgantown, MS | 1,860 | 30 | 40.0% |