| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 21°F | 39°F | 29°F | 2.6" |
| February | 22°F | 41°F | 31°F | 2.0" |
| March | 34°F | 56°F | 44°F | 3.3" |
| April | 44°F | 68°F | 55°F | 5.8" |
| May | 53°F | 76°F | 65°F | 4.3" |
| June | 63°F | 85°F | 73°F | 6.3" |
| July | 64°F | 87°F | 75°F | 4.5" |
| August | 62°F | 86°F | 74°F | 2.3" |
| September | 55°F | 80°F | 67°F | 2.9" |
| October | 44°F | 68°F | 55°F | 3.5" |
| November | 33°F | 55°F | 43°F | 2.7" |
| December | 26°F | 43°F | 34°F | 3.4" |
| Index | Rockville | Indiana | National |
| Air quality index | 45 | 56 | 42 |
| Pollution index | 1,601,640 | 2,719,453 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 237 |
| Days with moderate air quality | 127 |
| Days w/ poor A.Q. for sensitive groups | 1 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.004% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.040% |
| Mercury | 0.290% |
| City | Population | Air Quality Index | National Avg. |
| Lake Holiday, IN | 1,376 | 42 | 16.0% |
| Alamo, IN | 69 | 42 | 16.0% |
| Carbon, IN | 393 | 45 | 10.0% |
| Shepardsville, IN | 117 | 45 | 10.0% |
| Dana, IN | 691 | 45 | 10.0% |
| Rockville, IN | 2,304 | 45 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| South Roxana, IL | 2,304 | 54 | 8.0% |
| Johnsonburg, PA | 2,304 | 35 | 30.0% |
| Maskinongé, QC | 2,304 | n/a | |
| Trenton, GA | 2,303 | 46 | 8.0% |
| Lyman, MS | 2,303 | 42 | 16.0% |
| Rockville, IN | 2,304 | 45 | 10.0% |
Here are the best places to live in Indiana
Check out the 10 most dangerous cities in Indiana
See the best places to live in Rockville
Safest States In The US