| 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 | Helena | Oklahoma | National |
| Air quality index | 40 | 55 | 42 |
| Pollution index | 249,709 | 1,271,533 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 292 |
| Days with moderate air quality | 72 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.003% |
| Carbon Tetrachloride | 0.000% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Carmen, OK | 364 | 40 | 20.0% |
| Jet, OK | 265 | 40 | 20.0% |
| Nash, OK | 208 | 40 | 20.0% |
| Cherokee, OK | 1,618 | 40 | 20.0% |
| Lahoma, OK | 489 | 40 | 20.0% |
| Helena, OK | 1,467 | 40 | 20.0% |
| City | Population | Air Quality Index | National Avg. |
| Kinsley, KS | 1,467 | 15 | 70.0% |
| Collinsville, MS | 1,467 | 36 | 28.0% |
| Fairmount, TN | 1,467 | 46 | 8.0% |
| Richmond, Subd. B, NS | 1,467 | n/a | |
| Grandview, MB | 1,467 | n/a | |
| Helena, OK | 1,467 | 40 | 20.0% |
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