Early autumn · Weather & things to do
Philadelphia in September
Philadelphia cools off: highs slip to 79°F (26°C), from 85°F in August, with lows of 59°F (15°C) and about 4.0 in (102 mm) of rain.
September opens the best stretch on our comfort score, at 83/100 (3rd of 12).
- Avg high
- 79°F (26°C)
- Avg low
- 59°F (15°C)
- Rain
- 4.0 in (102 mm)
- Humidity
- 74%
- Cloud cover
- 50%
- Daylight
- ~12 h 15 min
- Comfort score
- 83/100 · Great
What September feels like
Highs settle around 79°F (26°C), warm enough for short sleeves most of the day.
Nights cool to an average low of 59°F (15°C).
Showers are part of the month, adding up to about 4.0 in (102 mm).
Plan around September
September is one of Philadelphia's best months on the climate data.
- Last warm month for a while: October highs fall to 67°F.
- Opens the best-scoring stretch on our comfort score: April & May and September & October.
- Comfort improves from 70/100 in August to 83/100.
- Our Capital Cities Corridor route recommends Mar – Jun, so September falls outside its suggested window.
- Our Philadelphia, Longwood & Lancaster route is planned for Late Nov – Dec, a window set by the holiday season rather than the weather — September falls outside it.
What to pack for September
- Light, breathable clotheshighs average 79°F
- Packable rain jacket or umbrellaabout 4.0 in of rain
- Comfortable walking shoesmost places below are best reached on foot or with short walks
What to do in Philadelphia in September
September is good outdoor weather here, so these picks lean toward the open air.
Franklin Square
One of William Penn's original squares, with a carousel, mini golf and a holiday light show set to music in December.
Why now September scores 83/100 for comfort, good conditions for being outside.
Independence Hall
Where the Declaration of Independence and the Constitution were signed.
McGillin's Olde Ale House
Philadelphia's oldest continuously operating tavern, open since 1860.
Dilworth Park
Plaza on the west side of City Hall with an outdoor ice rink and a lit Wintergarden in the holiday season.
Why now Highs near 79°F and 4.0 in of monthly rain make this an easy outdoor pick.
Christmas Village in Philadelphia
German-style Christmas market in LOVE Park and around City Hall, with wooden stalls, ornaments, bratwurst and Glühwein.
Why now One to do outside while the weather is on your side.
Zahav
Michael Solomonov's Israeli restaurant, known for hummus and lamb shoulder.
Nearby in September
- Kennett Square in September~30 mi · highs 79°F, 4.4 in rain · similar daytime temperatures, about as wet
- Lancaster in September~61 mi · highs 79°F, 4.6 in rain · similar daytime temperatures, wetter
- New York City in September~81 mi · highs 74°F, 3.8 in rain · 3°C (6°F) cooler by day, about as wet
- Manhattan in September~85 mi · highs 77°F, 4.1 in rain · 1°C (2°F) cooler by day, about as wet
These averages also cover Broad Street & South Philly and Center City & Penn's Landing.
NASA POWER 2001–2025 monthly averages on a ~50 km grid. Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Philadelphia in September: quick answers
Is September a good time to visit Philadelphia?
Yes. On the climate data it's one of the best months, scoring 83/100. Expect highs of 79°F (26°C) and 4.0 in (102 mm) of rain. Our Capital Cities Corridor route recommends Mar – Jun, so September is outside its suggested window.
How hot is Philadelphia in September?
Average highs are 79°F (26°C) and average lows 59°F (15°C), making it the 4th-warmest month by daytime highs.
Does it rain a lot in Philadelphia in September?
Some: about 4.0 in (102 mm) of rain falls across September on average, the 6th-wettest month of the year. The annual total is about 48.3 in (1228 mm).
What should I pack for Philadelphia in September?
Bring light, breathable clothes (highs average 79°F), packable rain jacket or umbrella (about 4.0 in of rain) and comfortable walking shoes (most places below are best reached on foot or with short walks).
More on Philadelphia
Planning Philadelphia in September?
Share this September plan with your group, poll everyone on dates and keep the packing list in one place.