| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 36°F | 58°F | 46°F | 5.8" |
| February | 38°F | 61°F | 48°F | 6.2" |
| March | 46°F | 70°F | 57°F | 6.3" |
| April | 52°F | 78°F | 65°F | 6.7" |
| May | 60°F | 84°F | 71°F | 3.8" |
| June | 69°F | 92°F | 79°F | 5.1" |
| July | 71°F | 93°F | 81°F | 4.5" |
| August | 71°F | 93°F | 81°F | 4.8" |
| September | 65°F | 88°F | 75°F | 4.0" |
| October | 52°F | 78°F | 64°F | 3.5" |
| November | 43°F | 68°F | 54°F | 4.4" |
| December | 39°F | 61°F | 49°F | 6.1" |
| Index | Union | Alabama | National |
| Air quality index | 35 | 37 | 50 |
| Pollution index | 660,757 | 4,051,223 | 5,066,862 |
| Measurement | Total |
| Days measured | 264 |
| Days with good air quality | 240 |
| Days with moderate air quality | 24 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.003% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.003% |
| Mercury | 0.000% |
| City, State | Population | Air Quality Index | National Avg. |
| Aliceville, AL | 3,218 | 35 | 30% |
| Akron, AL | 252 | 35 | 30% |
| Eutaw, AL | 2,789 | 35 | 30% |
| Gainesville, AL | 274 | 36 | 28% |
| Union, AL | 260 | 35 | 30% |
| City, State | Population | Air Quality Index | National Avg. |
| Offerle, KS | 260 | 15 | 70% |
| Dwight, KS | 260 | 32 | 36% |
| Montrose, GA | 260 | 38 | 24% |
| Valley Head, WV | 260 | 31 | 38% |
| Seltzer, PA | 260 | 42 | 16% |
| Union, AL | 260 | 35 | 30% |
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