| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 26°F | 50°F | 36°F | 3.2" |
| February | 29°F | 53°F | 40°F | 3.9" |
| March | 40°F | 65°F | 51°F | 6.0" |
| April | 48°F | 73°F | 59°F | 6.3" |
| May | 57°F | 81°F | 68°F | 8.4" |
| June | 69°F | 91°F | 79°F | 10.2" |
| July | 72°F | 95°F | 83°F | 7.1" |
| August | 70°F | 94°F | 81°F | 6.8" |
| September | 62°F | 86°F | 73°F | 5.2" |
| October | 50°F | 74°F | 61°F | 8.8" |
| November | 39°F | 62°F | 49°F | 5.4" |
| December | 28°F | 49°F | 37°F | 3.3" |
| Index | Hennessey | Oklahoma | National |
| Air quality index | 48 | 55 | 42 |
| Pollution index | 721,709 | 1,271,533 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 204 |
| Days with moderate air quality | 159 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Drummond, OK | 432 | 40 | 20.0% |
| Waukomis, OK | 1,201 | 40 | 20.0% |
| Douglas, OK | 106 | 40 | 20.0% |
| Loyal, OK | 103 | 48 | 4.0% |
| Bison, OK | 32 | 48 | 4.0% |
| Hennessey, OK | 2,996 | 48 | 4.0% |
| City | Population | Air Quality Index | National Avg. |
| Stallion Springs, CA | 2,996 | 67 | 34.0% |
| Harriman, NY | 2,996 | 36 | 28.0% |
| Prescott, AR | 2,995 | 32 | 36.0% |
| Whetstone, AZ | 2,995 | 45 | 10.0% |
| Pembroke, NC | 2,997 | 30 | 40.0% |
| Hennessey, OK | 2,996 | 48 | 4.0% |
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