| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 31°F | 55°F | 42°F | 2.7" |
| February | 31°F | 58°F | 44°F | 2.6" |
| March | 39°F | 67°F | 52°F | 4.3" |
| April | 48°F | 76°F | 62°F | 4.1" |
| May | 56°F | 82°F | 68°F | 4.1" |
| June | 65°F | 90°F | 77°F | 4.8" |
| July | 69°F | 93°F | 80°F | 5.2" |
| August | 69°F | 91°F | 79°F | 4.9" |
| September | 62°F | 85°F | 72°F | 5.5" |
| October | 49°F | 75°F | 61°F | 3.4" |
| November | 38°F | 66°F | 51°F | 3.8" |
| December | 34°F | 58°F | 45°F | 4.1" |
| Index | Clayton | North Carolina | National |
| Air quality index | 46 | 35 | 42 |
| Pollution index | 227,321 | 2,789,538 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 239 |
| Days with moderate air quality | 126 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.003% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Micro, NC | 716 | 40 | 20.0% |
| Smithfield, NC | 13,082 | 40 | 20.0% |
| Four Oaks, NC | 2,278 | 40 | 20.0% |
| Pine Level, NC | 2,234 | 40 | 20.0% |
| Selma, NC | 7,159 | 40 | 20.0% |
| Clayton, NC | 24,066 | 46 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| Venice, FL | 24,063 | 38 | 24.0% |
| Moses Lake, WA | 24,055 | 18 | 64.0% |
| Carteret, NJ | 24,081 | 51 | 2.0% |
| Watertown, WI | 24,039 | 37 | 26.0% |
| Fairfax, VA | 24,037 | 47 | 6.0% |
| Clayton, NC | 24,066 | 46 | 8.0% |