| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 51°F | 72°F | 60°F | 2.9" |
| February | 55°F | 77°F | 64°F | 2.4" |
| March | 61°F | 82°F | 70°F | 4.1" |
| April | 67°F | 88°F | 76°F | 4.4" |
| May | 72°F | 91°F | 80°F | 7.5" |
| June | 76°F | 96°F | 84°F | 6.0" |
| July | 76°F | 96°F | 85°F | 12.6" |
| August | 77°F | 97°F | 86°F | 6.9" |
| September | 74°F | 93°F | 81°F | 9.5" |
| October | 67°F | 89°F | 77°F | 11.2" |
| November | 59°F | 81°F | 69°F | 4.4" |
| December | 54°F | 74°F | 62°F | 4.7" |
| Index | Llano Grande | Texas | National |
| Air quality index | 42 | 52 | 42 |
| Pollution index | 7,136,530 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 243 |
| Days with moderate air quality | 120 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.080% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.020% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Alamo, TX | 20,629 | 42 | 16.0% |
| Campo Verde, TX | 173 | 42 | 16.0% |
| Santa Rosa CDP, TX | 216 | 42 | 16.0% |
| Progreso, TX | 6,099 | 42 | 16.0% |
| Pharr, TX | 80,998 | 42 | 16.0% |
| Llano Grande, TX | 2,080 | 42 | 16.0% |
| City | Population | Air Quality Index | National Avg. |
| Fritz Creek, AK | 2,080 | 31 | 38.0% |
| Bottineau, ND | 2,080 | 36 | 28.0% |
| Waurika, OK | 2,080 | 26 | 48.0% |
| Wilson-Conococheague, MD | 2,081 | 40 | 20.0% |
| Troup, TX | 2,079 | 36 | 28.0% |
| Llano Grande, TX | 2,080 | 42 | 16.0% |