| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 36°F | 59°F | 46°F | 3.0" |
| February | 38°F | 62°F | 49°F | 3.4" |
| March | 45°F | 70°F | 57°F | 3.2" |
| April | 54°F | 79°F | 66°F | 2.8" |
| May | 62°F | 85°F | 73°F | 3.4" |
| June | 70°F | 92°F | 80°F | 4.6" |
| July | 73°F | 94°F | 82°F | 4.7" |
| August | 73°F | 92°F | 81°F | 5.5" |
| September | 67°F | 87°F | 76°F | 4.2" |
| October | 55°F | 78°F | 65°F | 4.0" |
| November | 43°F | 68°F | 54°F | 2.8" |
| December | 41°F | 63°F | 50°F | 4.3" |
| Index | Blythewood | South Carolina | National |
| Air quality index | 43 | 37 | 42 |
| Pollution index | 1,152,050 | 3,620,438 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 264 |
| Days with moderate air quality | 99 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.005% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Forest Acres, SC | 10,529 | 43 | 14.0% |
| Irmo, SC | 12,834 | 43 | 14.0% |
| Winnsboro, SC | 3,295 | 43 | 14.0% |
| Ridgeway, SC | 304 | 43 | 14.0% |
| Lexington, SC | 22,445 | 43 | 14.0% |
| Blythewood, SC | 3,758 | 43 | 14.0% |
| City | Population | Air Quality Index | National Avg. |
| Pine Level, AL | 3,758 | 52 | 4.0% |
| Lloyd Harbor, NY | 3,758 | 43 | 14.0% |
| Ashburn, GA | 3,757 | 40 | 20.0% |
| Victoria, Subd. B, NS | 3,757 | n/a | |
| Thompsonville, PA | 3,759 | 56 | 12.0% |
| Blythewood, SC | 3,758 | 43 | 14.0% |