| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 26°F | 40°F | 32°F | 4.1" |
| February | 19°F | 38°F | 28°F | 2.9" |
| March | 29°F | 49°F | 39°F | 4.6" |
| April | 40°F | 63°F | 51°F | 6.6" |
| May | 47°F | 74°F | 61°F | 2.5" |
| June | 61°F | 84°F | 72°F | 9.0" |
| July | 64°F | 84°F | 74°F | 11.6" |
| August | 65°F | 84°F | 74°F | 4.1" |
| September | 57°F | 81°F | 69°F | 2.3" |
| October | 50°F | 69°F | 58°F | 8.8" |
| November | 34°F | 55°F | 44°F | 3.7" |
| December | 25°F | 40°F | 33°F | 5.2" |
| Index | Lancaster | Pennsylvania | National |
| Air quality index | 45 | 45 | 42 |
| Pollution index | 11,091,200 | 4,584,805 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 238 |
| Days with moderate air quality | 117 |
| Days w/ poor A.Q. for sensitive groups | 9 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.140% |
| Carbon Tetrachloride | 0.030% |
| Lead | 0.310% |
| Mercury | 0.004% |
| City | Population | Air Quality Index | National Avg. |
| Yorkana, PA | 207 | 41 | 18.0% |
| Maytown, PA | 4,130 | 41 | 18.0% |
| Rheems, PA | 2,836 | 41 | 18.0% |
| Windsor, PA | 1,265 | 41 | 18.0% |
| Felton, PA | 644 | 41 | 18.0% |
| Lancaster, PA | 59,321 | 45 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| Royal Oak, MI | 59,256 | 56 | 12.0% |
| Bartlett, TN | 59,252 | 45 | 10.0% |
| Gardena, CA | 59,401 | 72 | 44.0% |
| Vineland, NJ | 59,405 | 40 | 20.0% |
| Brookline, MA | 59,223 | 43 | 14.0% |
| Lancaster, PA | 59,321 | 45 | 10.0% |
Here are the best places to live in Pennsylvania
These are the largest cities in Pennsylvania
Safest States In The US
Safest Cities In The US