April through early June (spring) or September through October (fall). Mild, pleasant temperatures (spring highs in the mid-60s to low 80s°F; fall highs in the mid-60s to mid-70s°F) allow comfortable outdoor exploration of historic sites; lower crowds and more affordable accommodation than summer peak; spring brings the Penn Relays (late April) and cherry blossoms; fall offers the Philadelphia Fringe Festival and Philadelphia Film Festival
| Month | High (°F) | Low (°F) | Notes |
|---|---|---|---|
| Jan | 41 | 27 | crisp & changeable |
| Feb | 44 | 28 | crisp & changeable |
| Mar | 52 | 34 | cool & changeable |
| Apr | 64 | 45 | mild & changeable |
| May | 73 | 55 | warm & changeable |
| Jun | 82 | 64 | warm & changeable |
| Jul | 87 | 70 | hot & changeable |
| Aug | 84 | 68 | warm & changeable |
| Sep | 78 | 62 | warm & changeable |
| Oct | 66 | 51 | mild & changeable |
| Nov | 55 | 40 | cool & changeable |
| Dec | 46 | 32 | cool & changeable |