| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 25°F | 54°F | 37°F | 6.4" |
| February | 28°F | 60°F | 42°F | 2.7" |
| March | 36°F | 69°F | 51°F | 4.8" |
| April | 42°F | 76°F | 58°F | 6.1" |
| May | 51°F | 82°F | 66°F | 6.7" |
| June | 62°F | 92°F | 76°F | 5.6" |
| July | 65°F | 92°F | 78°F | 6.0" |
| August | 64°F | 91°F | 76°F | 6.9" |
| September | 57°F | 84°F | 69°F | 6.9" |
| October | 45°F | 76°F | 59°F | 6.5" |
| November | 34°F | 65°F | 48°F | 1.8" |
| December | 26°F | 54°F | 38°F | 3.0" |
| Index | Portales | New Mexico | National |
| Air quality index | 15 | 37 | 42 |
| Pollution index | 390,466 | 2,051,791 | 2,726,193 |
| Measurement | Total |
| Days measured | 59 |
| Days with good air quality | 59 |
| Days with moderate air quality | 0 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| 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. |
| Cannon AFB, NM | 2,527 | 15 | 70.0% |
| Floyd, NM | 91 | 15 | 70.0% |
| Portales, NM | 11,713 | 15 | 70.0% |
| City | Population | Air Quality Index | National Avg. |
| Arlington, TN | 11,715 | 45 | 10.0% |
| Stratford, PE | 11,716 | n/a | |
| Grafton, WI | 11,718 | 44 | 12.0% |
| Webster, MA | 11,719 | 40 | 20.0% |
| Florham Park, NJ | 11,719 | 51 | 2.0% |
| Portales, NM | 11,713 | 15 | 70.0% |
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