| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 39°F | 65°F | 50°F | 3.2" |
| February | 39°F | 68°F | 53°F | 3.5" |
| March | 46°F | 74°F | 59°F | 3.2" |
| April | 53°F | 81°F | 67°F | 3.3" |
| May | 61°F | 86°F | 73°F | 4.4" |
| June | 70°F | 92°F | 80°F | 6.5" |
| July | 73°F | 94°F | 81°F | 5.3" |
| August | 73°F | 93°F | 81°F | 6.1" |
| September | 68°F | 89°F | 77°F | 4.0" |
| October | 57°F | 81°F | 68°F | 4.2" |
| November | 45°F | 73°F | 58°F | 2.1" |
| December | 43°F | 68°F | 54°F | 4.2" |
| Index | Hardeeville | South Carolina | National |
| Air quality index | 39 | 37 | 42 |
| Pollution index | 1,428,370 | 3,620,438 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 295 |
| Days with moderate air quality | 70 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.020% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.040% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Ridgeland, SC | 4,013 | 29 | 42.0% |
| Port Wentworth, GA | 9,153 | 39 | 22.0% |
| Bluffton, SC | 23,896 | 39 | 22.0% |
| Bloomingdale, GA | 2,890 | 39 | 22.0% |
| Savannah, GA | 148,994 | 39 | 22.0% |
| Hardeeville, SC | 7,055 | 39 | 22.0% |
| City | Population | Air Quality Index | National Avg. |
| Heathrow, FL | 7,056 | 37 | 26.0% |
| Huron, OH | 7,056 | 50 | = 100 |
| Freeland, MI | 7,053 | 26 | 48.0% |
| Sandston, VA | 7,053 | 44 | 12.0% |
| Valley Park, MO | 7,052 | 54 | 8.0% |
| Hardeeville, SC | 7,055 | 39 | 22.0% |