| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 33°F | 62°F | 46°F | 3.3" |
| February | 35°F | 64°F | 49°F | 4.2" |
| March | 41°F | 73°F | 56°F | 3.8" |
| April | 48°F | 80°F | 64°F | 3.4" |
| May | 57°F | 86°F | 71°F | 3.1" |
| June | 66°F | 93°F | 79°F | 4.1" |
| July | 69°F | 95°F | 81°F | 4.2" |
| August | 70°F | 94°F | 80°F | 5.0" |
| September | 63°F | 89°F | 75°F | 2.8" |
| October | 50°F | 81°F | 64°F | 2.5" |
| November | 39°F | 71°F | 54°F | 2.9" |
| December | 37°F | 65°F | 50°F | 5.3" |
| Index | Harrison | Georgia | National |
| Air quality index | 42 | 41 | 50 |
| Pollution index | 335,277 | 3,237,553 | 5,066,862 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 251 |
| Days with moderate air quality | 112 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City, State | Population | Air Quality Index | National Avg. |
| Tennille, GA | 1,649 | 41 | 18% |
| Oconee, GA | 305 | 41 | 18% |
| Wrightsville, GA | 3,669 | 41 | 18% |
| Deepstep, GA | 164 | 41 | 18% |
| Sandersville, GA | 5,776 | 41 | 18% |
| Harrison, GA | 495 | 42 | 16% |
| City, State | Population | Air Quality Index | National Avg. |
| Bird City, KS | 495 | 19 | 62% |
| Jewell, KS | 495 | 265 | 430% |
| Houston Acres, KY | 495 | 55 | 10% |
| Falcon Mesa, TX | 495 | 38 | 24% |
| McCoole, MD | 495 | 32 | 36% |
| Harrison, GA | 495 | 42 | 16% |