| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 35°F | 57°F | 45°F | 4.2" |
| February | 37°F | 60°F | 47°F | 3.4" |
| March | 45°F | 69°F | 56°F | 4.7" |
| April | 53°F | 77°F | 64°F | 5.3" |
| May | 60°F | 83°F | 71°F | 4.5" |
| June | 69°F | 91°F | 79°F | 3.2" |
| July | 71°F | 93°F | 81°F | 3.3" |
| August | 71°F | 94°F | 81°F | 4.2" |
| September | 64°F | 88°F | 75°F | 3.4" |
| October | 52°F | 78°F | 63°F | 4.7" |
| November | 43°F | 67°F | 54°F | 3.8" |
| December | 37°F | 58°F | 46°F | 6.0" |
| Index | Harrell | Arkansas | National |
| Air quality index | 35 | 38 | 42 |
| Pollution index | 604,854 | 1,487,822 | 2,726,193 |
| Measurement | Total |
| Days measured | 241 |
| Days with good air quality | 196 |
| Days with moderate air quality | 45 |
| 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 | 0.000% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Hampton, AR | 1,697 | 35 | 30.0% |
| Calion, AR | 453 | 35 | 30.0% |
| Hermitage, AR | 881 | 35 | 30.0% |
| Norphlet, AR | 655 | 35 | 30.0% |
| Tinsman, AR | 43 | 35 | 30.0% |
| Harrell, AR | 355 | 35 | 30.0% |
| City | Population | Air Quality Index | National Avg. |
| Patterson, AR | 355 | 45 | 10.0% |
| Shirley, AR | 355 | 36 | 28.0% |
| Crows Landing, CA | 355 | 49 | 2.0% |
| Mad River, CA | 355 | 27 | 46.0% |
| Orick, CA | 355 | 20 | 60.0% |
| Harrell, AR | 355 | 35 | 30.0% |