Weather history and climate summary information is available for the following locations:
- Allentown
- Erie
- Harrisburg
- Philadelphia
- Pittsburgh
- Pittsburgh (pennsylva)
- Scranton
Warmest January Days
The warmest January days in Pennsylvania are:
| Pittsburgh (pennsylva), Pennsylvania | 1950 | 73.4°F |
| Philadelphia, Pennsylvania | 2007 | 73°F |
| Philadelphia, Pennsylvania | 2002 | 72°F |
| Pittsburgh (pennsylva), Pennsylvania | 2002 | 72°F |
| Pittsburgh, Pennsylvania | 1999 | 71.6°F |
Coldest January Days
The coldest January days in Pennsylvania were:
| Pittsburgh, Pennsylvania | 1982 | -26.9°F |
| Pittsburgh (pennsylva), Pennsylvania | 1994 | -22°F |
| Scranton, Pennsylvania | 1994 | -21.1°F |
| Pittsburgh, Pennsylvania | 1994 | -20°F |
| Pittsburgh (pennsylva), Pennsylvania | 1985 | -18°F |
Wettest January Days
The wettest single days in January occurred:
| Philadelphia, Pennsylvania | 1982 | 3.9 inches |
| Pittsburgh (pennsylva), Pennsylvania | 1973 | 3.5 inches |
| Scranton, Pennsylvania | 1973 | 2.5 inches |
| Allentown, Pennsylvania | 1973 | 2.4 inches |
| Philadelphia, Pennsylvania | 1979 | 2.3 inches |