| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 26°F | 59°F | 40°F | 0.8" |
| February | 29°F | 63°F | 44°F | 0.8" |
| March | 38°F | 74°F | 54°F | 1.2" |
| April | 45°F | 81°F | 62°F | 1.2" |
| May | 54°F | 86°F | 69°F | 3.1" |
| June | 65°F | 95°F | 79°F | 2.2" |
| July | 68°F | 94°F | 81°F | 2.6" |
| August | 66°F | 94°F | 79°F | 2.1" |
| September | 59°F | 87°F | 72°F | 3.1" |
| October | 48°F | 80°F | 62°F | 1.7" |
| November | 35°F | 70°F | 51°F | 0.5" |
| December | 27°F | 59°F | 41°F | 0.9" |
| Index | Sundown | Texas | National |
| Air quality index | 25 | 52 | 42 |
| Pollution index | 461,566 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 330 |
| Days with good air quality | 316 |
| Days with moderate air quality | 13 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.004% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Opdyke West, TX | 234 | 25 | 50.0% |
| Whiteface, TX | 341 | 25 | 50.0% |
| Levelland, TX | 13,885 | 25 | 50.0% |
| Sundown, TX | 1,514 | 25 | 50.0% |
| City | Population | Air Quality Index | National Avg. |
| Vance, AL | 1,514 | 35 | 30.0% |
| Nederland, CO | 1,514 | 47 | 6.0% |
| Auburn, KY | 1,514 | 43 | 14.0% |
| Silver Grove, KY | 1,514 | 54 | 8.0% |
| Hinsdale, NH | 1,514 | 34 | 32.0% |
| Sundown, TX | 1,514 | 25 | 50.0% |