| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 18°F | 34°F | 25°F | 2.6" |
| February | 18°F | 35°F | 25°F | 2.2" |
| March | 27°F | 48°F | 37°F | 3.2" |
| April | 37°F | 62°F | 49°F | 3.5" |
| May | 47°F | 72°F | 59°F | 3.9" |
| June | 55°F | 78°F | 66°F | 5.3" |
| July | 59°F | 83°F | 70°F | 3.8" |
| August | 57°F | 81°F | 68°F | 4.0" |
| September | 51°F | 74°F | 61°F | 3.3" |
| October | 41°F | 63°F | 51°F | 3.9" |
| November | 31°F | 51°F | 40°F | 2.5" |
| December | 24°F | 39°F | 31°F | 3.7" |
| Index | Grampian | Pennsylvania | National |
| Air quality index | 33 | 45 | 42 |
| Pollution index | 2,854,150 | 4,584,805 | 2,726,193 |
| Measurement | Total |
| Days measured | 359 |
| Days with good air quality | 357 |
| Days with moderate air quality | 2 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.030% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.010% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Troutville, PA | 236 | 33 | 34.0% |
| Hyde, PA | 1,361 | 33 | 34.0% |
| Glen Campbell, PA | 191 | 33 | 34.0% |
| New Washington, PA | 26 | 33 | 34.0% |
| Sykesville, PA | 971 | 33 | 34.0% |
| Grampian, PA | 479 | 33 | 34.0% |
| City | Population | Air Quality Index | National Avg. |
| Altona, CO | 479 | 47 | 6.0% |
| Lisbon, FL | 479 | 38 | 24.0% |
| McCallsburg, IA | 479 | 37 | 26.0% |
| Otho, IA | 479 | 37 | 26.0% |
| Salix, IA | 479 | 35 | 30.0% |
| Grampian, PA | 479 | 33 | 34.0% |
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