| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 38°F | 53°F | 44°F | 9.4" |
| February | 38°F | 56°F | 45°F | 3.6" |
| March | 48°F | 70°F | 56°F | 5.2" |
| April | 52°F | 74°F | 61°F | 6.9" |
| May | 63°F | 84°F | 72°F | 4.2" |
| June | 71°F | 91°F | 80°F | 3.0" |
| July | 72°F | 90°F | 79°F | 7.8" |
| August | 74°F | 96°F | 84°F | 6.3" |
| September | 67°F | 88°F | 76°F | 11.9" |
| October | 55°F | 76°F | 64°F | 17.9" |
| November | 46°F | 68°F | 55°F | 5.5" |
| December | 36°F | 56°F | 44°F | 9.2" |
| Index | Hazen | Arkansas | National |
| Air quality index | 45 | 38 | 42 |
| Pollution index | 1,391,300 | 1,487,822 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 235 |
| Days with moderate air quality | 130 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.001% |
| Benzene | 0.020% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.050% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| De Valls Bluff, AR | 615 | 45 | 10.0% |
| Roe, AR | 84 | 45 | 10.0% |
| Ulm, AR | 244 | 45 | 10.0% |
| Carlisle, AR | 2,334 | 45 | 10.0% |
| Des Arc, AR | 1,384 | 45 | 10.0% |
| Hazen, AR | 1,792 | 45 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| Walnut Grove, GA | 1,792 | 44 | 12.0% |
| Decatur, MS | 1,792 | 36 | 28.0% |
| Big Beaver, PA | 1,792 | 31 | 38.0% |
| Farley, IA | 1,793 | 29 | 42.0% |
| Zilwaukee, MI | 1,791 | 26 | 48.0% |
| Hazen, AR | 1,792 | 45 | 10.0% |