| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 38°F | 62°F | 49°F | 8.0" |
| February | 43°F | 67°F | 53°F | 3.9" |
| March | 50°F | 74°F | 61°F | 8.5" |
| April | 58°F | 80°F | 68°F | 6.8" |
| May | 65°F | 86°F | 75°F | 10.2" |
| June | 72°F | 93°F | 83°F | 10.1" |
| July | 75°F | 95°F | 85°F | 15.2" |
| August | 74°F | 97°F | 85°F | 11.2" |
| September | 68°F | 90°F | 79°F | 6.6" |
| October | 58°F | 82°F | 70°F | 2.8" |
| November | 49°F | 71°F | 59°F | 5.0" |
| December | 41°F | 63°F | 51°F | 4.3" |
| Index | Thrall | Texas | National |
| Air quality index | 44 | 52 | 42 |
| Pollution index | 692,760 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 249 |
| Days with moderate air quality | 114 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Bartlett, TX | 1,703 | 42 | 16.0% |
| Granger, TX | 1,189 | 42 | 16.0% |
| Hutto, TX | 27,658 | 44 | 12.0% |
| Taylor, TX | 17,845 | 44 | 12.0% |
| Thorndale, TX | 1,350 | 44 | 12.0% |
| Thrall, TX | 734 | 44 | 12.0% |
| City | Population | Air Quality Index | National Avg. |
| Tyronza, AR | 734 | 45 | 10.0% |
| Mendocino, CA | 734 | 33 | 34.0% |
| Onaga, KS | 734 | 32 | 36.0% |
| Kerkhoven, MN | 734 | 32 | 36.0% |
| Chestertown, NY | 734 | 36 | 28.0% |
| Thrall, TX | 734 | 44 | 12.0% |