| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 37°F | 57°F | 46°F | 6.0" |
| February | 41°F | 61°F | 49°F | 5.2" |
| March | 49°F | 70°F | 58°F | 6.8" |
| April | 56°F | 77°F | 65°F | 9.0" |
| May | 63°F | 83°F | 72°F | 6.4" |
| June | 72°F | 91°F | 81°F | 7.2" |
| July | 75°F | 94°F | 84°F | 8.7" |
| August | 75°F | 95°F | 84°F | 5.1" |
| September | 67°F | 89°F | 77°F | 10.9" |
| October | 57°F | 79°F | 67°F | 13.0" |
| November | 48°F | 68°F | 57°F | 7.8" |
| December | 40°F | 59°F | 48°F | 7.7" |
| Index | Sulphur Springs | Texas | National |
| Air quality index | 36 | 52 | 42 |
| Pollution index | 2,654,360 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 364 |
| Days with good air quality | 326 |
| Days with moderate air quality | 37 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.003% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Como, TX | 732 | 36 | 28.0% |
| Yantis, TX | 362 | 36 | 28.0% |
| Point, TX | 1,123 | 51 | 2.0% |
| Cumby, TX | 836 | 51 | 2.0% |
| Tira, TX | 355 | 325 | 550.0% |
| Sulphur Springs, TX | 16,573 | 36 | 28.0% |
| City | Population | Air Quality Index | National Avg. |
| Fort Mohave, AZ | 16,571 | 13 | 74.0% |
| Waxhaw, NC | 16,569 | 49 | 2.0% |
| Brunswick, ME | 16,566 | 31 | 38.0% |
| White Center, WA | 16,584 | 45 | 10.0% |
| Southchase, FL | 16,590 | 39 | 22.0% |
| Sulphur Springs, TX | 16,573 | 36 | 28.0% |