| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 23°F | 36°F | 29°F | 3.5" |
| February | 27°F | 43°F | 34°F | 1.7" |
| March | 36°F | 56°F | 45°F | 5.3" |
| April | 43°F | 65°F | 53°F | 5.1" |
| May | 53°F | 74°F | 63°F | 3.8" |
| June | 61°F | 83°F | 71°F | 3.9" |
| July | 61°F | 88°F | 75°F | 2.7" |
| August | 57°F | 86°F | 71°F | 5.4" |
| September | 54°F | 78°F | 65°F | 8.2" |
| October | 45°F | 66°F | 54°F | 4.8" |
| November | 35°F | 54°F | 43°F | 4.4" |
| December | 27°F | 40°F | 33°F | 5.4" |
| Index | Warren | Indiana | National |
| Air quality index | 31 | 56 | 42 |
| Pollution index | 1,644,960 | 2,719,453 | 2,726,193 |
| Measurement | Total |
| Days measured | 355 |
| Days with good air quality | 345 |
| Days with moderate air quality | 10 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.002% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.040% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Bluffton, IN | 10,527 | 31 | 38.0% |
| Van Buren, IN | 926 | 31 | 38.0% |
| Markle, IN | 1,540 | 31 | 38.0% |
| Andrews, IN | 1,211 | 31 | 38.0% |
| Mount Etna, IN | 136 | 31 | 38.0% |
| Warren, IN | 1,247 | 31 | 38.0% |
| City | Population | Air Quality Index | National Avg. |
| Tok, AK | 1,247 | 38 | 24.0% |
| Mansfield, AR | 1,247 | 36 | 28.0% |
| Schoolcraft, MI | 1,247 | 38 | 24.0% |
| Pender, NE | 1,247 | 35 | 30.0% |
| Talkeetna, AK | 1,246 | 31 | 38.0% |
| Warren, IN | 1,247 | 31 | 38.0% |