| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 33°F | 58°F | 44°F | 2.9" |
| February | 38°F | 61°F | 48°F | 1.9" |
| March | 47°F | 70°F | 57°F | 3.9" |
| April | 54°F | 77°F | 65°F | 4.2" |
| May | 62°F | 83°F | 72°F | 4.7" |
| June | 71°F | 92°F | 81°F | 3.4" |
| July | 73°F | 96°F | 84°F | 2.7" |
| August | 74°F | 96°F | 84°F | 2.1" |
| September | 66°F | 90°F | 77°F | 2.9" |
| October | 54°F | 80°F | 66°F | 4.6" |
| November | 45°F | 68°F | 56°F | 3.5" |
| December | 36°F | 58°F | 46°F | 3.1" |
| Index | Melissa | Texas | National |
| Air quality index | 51 | 52 | 42 |
| Pollution index | 723,856 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 181 |
| Days with moderate air quality | 155 |
| Days w/ poor A.Q. for sensitive groups | 28 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.003% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Celina, TX | 13,935 | 51 | 2.0% |
| Lowry Crossing, TX | 1,245 | 51 | 2.0% |
| Princeton, TX | 12,578 | 51 | 2.0% |
| Allen, TX | 107,542 | 51 | 2.0% |
| Lucas, TX | 8,398 | 51 | 2.0% |
| Melissa, TX | 11,030 | 51 | 2.0% |
| City | Population | Air Quality Index | National Avg. |
| Comstock Park, MI | 11,032 | 38 | 24.0% |
| East Liverpool, OH | 11,032 | 6 | 88.0% |
| Arkadelphia, AR | 11,027 | 32 | 36.0% |
| Millington, TN | 11,024 | 45 | 10.0% |
| Yazoo City, MS | 11,022 | 44 | 12.0% |
| Melissa, TX | 11,030 | 51 | 2.0% |