| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 54°F | 69°F | 60°F | 2.1" |
| February | 58°F | 72°F | 64°F | 2.4" |
| March | 63°F | 78°F | 70°F | 6.5" |
| April | 67°F | 82°F | 73°F | 2.1" |
| May | 73°F | 87°F | 79°F | 4.9" |
| June | 78°F | 91°F | 84°F | 6.0" |
| July | 79°F | 92°F | 85°F | 9.4" |
| August | 78°F | 93°F | 85°F | 7.6" |
| September | 76°F | 90°F | 83°F | 11.2" |
| October | 69°F | 85°F | 77°F | 6.2" |
| November | 62°F | 79°F | 70°F | 5.7" |
| December | 57°F | 75°F | 64°F | 1.4" |
| Index | Los Fresnos | Texas | National |
| Air quality index | 44 | 52 | 42 |
| Pollution index | 7,136,530 | 2,009,300 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 236 |
| Days with moderate air quality | 129 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| 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. |
| Brownsville, TX | 189,413 | 44 | 12.0% |
| San Pedro, TX | 189 | 44 | 12.0% |
| Del Mar Heights, TX | 169 | 44 | 12.0% |
| Indian Lake, TX | 987 | 44 | 12.0% |
| La Paloma, TX | 4,278 | 44 | 12.0% |
| Los Fresnos, TX | 8,033 | 44 | 12.0% |
| City | Population | Air Quality Index | National Avg. |
| Lampasas, TX | 8,034 | 42 | 16.0% |
| Jerseyville, IL | 8,030 | 54 | 8.0% |
| Grove City, PA | 8,030 | 31 | 38.0% |
| Aberdeen, NC | 8,036 | 41 | 18.0% |
| The Blue Mountains, ON | 8,029 | n/a | |
| Los Fresnos, TX | 8,033 | 44 | 12.0% |