| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 19°F | 33°F | 26°F | 2.7" |
| February | 18°F | 34°F | 26°F | 2.5" |
| March | 28°F | 46°F | 36°F | 3.3" |
| April | 39°F | 60°F | 48°F | 3.6" |
| May | 49°F | 70°F | 59°F | 3.8" |
| June | 57°F | 77°F | 66°F | 5.2" |
| July | 61°F | 81°F | 70°F | 4.7" |
| August | 60°F | 79°F | 69°F | 4.2" |
| September | 54°F | 73°F | 63°F | 4.2" |
| October | 44°F | 61°F | 52°F | 4.6" |
| November | 34°F | 50°F | 41°F | 3.1" |
| December | 25°F | 38°F | 31°F | 3.6" |
| Index | Jamestown | Pennsylvania | National |
| Air quality index | 42 | 45 | 42 |
| Pollution index | 3,855,270 | 4,584,805 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 276 |
| Days with moderate air quality | 89 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.003% |
| Benzene | 0.040% |
| Carbon Tetrachloride | 0.010% |
| Lead | 0.020% |
| Mercury | 0.001% |
| City | Population | Air Quality Index | National Avg. |
| Fredonia, PA | 320 | 31 | 38.0% |
| Lake Latonka, PA | 756 | 31 | 38.0% |
| Sheakleyville, PA | 140 | 31 | 38.0% |
| Conneaut Lakeshore, PA | 2,036 | 34 | 32.0% |
| Harmonsburg, PA | 366 | 34 | 32.0% |
| Jamestown, PA | 761 | 42 | 16.0% |
| City | Population | Air Quality Index | National Avg. |
| Manokotak, AK | 761 | 31 | 38.0% |
| Independence, CA | 761 | 47 | 6.0% |
| Duck Key, FL | 761 | 41 | 18.0% |
| Ventura, IA | 761 | 15 | 70.0% |
| Challis, ID | 761 | 36 | 28.0% |
| Jamestown, PA | 761 | 42 | 16.0% |
Here are the best places to live in Pennsylvania
Check out the 10 safest cities in Pennsylvania
These are the 10 cheapest cities in Pennsylvania
Most Dangerous Cities In The US