| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 43°F | 61°F | 51°F | 5.6" |
| February | 46°F | 65°F | 54°F | 6.0" |
| March | 51°F | 74°F | 61°F | 5.4" |
| April | 54°F | 78°F | 65°F | 4.2" |
| May | 63°F | 85°F | 73°F | 5.1" |
| June | 70°F | 92°F | 80°F | 3.3" |
| July | 72°F | 91°F | 80°F | 9.6" |
| August | 72°F | 94°F | 82°F | 6.3" |
| September | 69°F | 92°F | 79°F | 3.3" |
| October | 56°F | 82°F | 68°F | 6.5" |
| November | 50°F | 74°F | 60°F | 9.6" |
| December | 41°F | 66°F | 52°F | 5.7" |
| Index | Montgomery | Texas | National |
| Air quality index | 52 | 52 | 42 |
| Pollution index | 898,232 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 171 |
| Days with moderate air quality | 163 |
| Days w/ poor A.Q. for sensitive groups | 26 |
| Days with unhealthy air quality | 4 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.001% |
| Lead | 0.004% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| New Waverly, TX | 940 | 52 | 4.0% |
| Magnolia, TX | 2,910 | 52 | 4.0% |
| Panorama Village, TX | 2,740 | 52 | 4.0% |
| Pinehurst, TX | 5,165 | 52 | 4.0% |
| Todd Mission, TX | 126 | 52 | 4.0% |
| Montgomery, TX | 2,260 | 52 | 4.0% |
| City | Population | Air Quality Index | National Avg. |
| Buckhorn, CA | 2,260 | 39 | 22.0% |
| Toledo, IA | 2,260 | 39 | 22.0% |
| Bay City, OR | 2,260 | 32 | 36.0% |
| West Interlake, MB | 2,260 | n/a | |
| Aviston, IL | 2,259 | 54 | 8.0% |
| Montgomery, TX | 2,260 | 52 | 4.0% |