What is the weather like in Boston vs Philadelphia in September?

In September, Boston averages 24°C high / 15°C low with about 83 mm of rain; Philadelphia averages 27°C high / 18°C low with about 101 mm.

Boston vs Philadelphia in September

Boston is the better pick in September — 90 vs 81 on SeasonMap's comfort score. Boston is warm, rainy, clean air, while Philadelphia is warm, rainy, clean air.

Boston vs Philadelphia — September climate, side by side

	🇺🇸 Boston	🇺🇸 Philadelphia
Comfort score	90/100 (S)	81/100 (A)
Feels-like high	24°C	28°C
Avg high / low	24° / 15°	27° / 18°
Rainfall	83 mm	101 mm
Rainy days	7	7
Humidity	76%	72%
Air quality (AQI)	46	45

Monthly climate normals (ERA5 reanalysis). Comfort scores are SeasonMap estimates.

Month by month

Boston vs Philadelphia in September — FAQ

Is September better in Boston or Philadelphia?: Boston is the better pick in September — 90 vs 81 on SeasonMap's comfort score. Boston is warm, rainy, clean air, while Philadelphia is warm, rainy, clean air.
What is the weather like in Boston vs Philadelphia in September?: In September, Boston averages 24°C high / 15°C low with about 83 mm of rain; Philadelphia averages 27°C high / 18°C low with about 101 mm.