| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 40°F | 58°F | 47°F | 5.5" |
| February | 43°F | 63°F | 51°F | 2.7" |
| March | 50°F | 72°F | 60°F | 10.4" |
| April | 55°F | 77°F | 64°F | 3.3" |
| May | 64°F | 82°F | 72°F | 8.5" |
| June | 71°F | 90°F | 79°F | 14.0" |
| July | 72°F | 90°F | 80°F | 5.9" |
| August | 73°F | 93°F | 82°F | 6.1" |
| September | 70°F | 91°F | 79°F | 5.1" |
| October | 58°F | 82°F | 69°F | 4.0" |
| November | 50°F | 73°F | 60°F | 7.3" |
| December | 38°F | 64°F | 50°F | 0.9" |
| Index | Bertram | Texas | National |
| Air quality index | 42 | 52 | 42 |
| Pollution index | 1,922,400 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 284 |
| Days with moderate air quality | 79 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Burnet, TX | 6,587 | 42 | 16.0% |
| Liberty Hill, TX | 4,793 | 44 | 12.0% |
| Leander, TX | 62,512 | 44 | 12.0% |
| Marble Falls, TX | 6,990 | 44 | 12.0% |
| Meadowlakes, TX | 2,336 | 44 | 12.0% |
| Bertram, TX | 1,931 | 42 | 16.0% |
| City | Population | Air Quality Index | National Avg. |
| Granger, IA | 1,931 | 39 | 22.0% |
| Anson, TX | 1,931 | 26 | 48.0% |
| Kamsack, SK | 1,931 | n/a | |
| Kersey, CO | 1,932 | 45 | 10.0% |
| Charlotte Park, FL | 1,932 | 36 | 28.0% |
| Bertram, TX | 1,931 | 42 | 16.0% |