Best time to visit Philadelphia

Re-score for me — drag the dial — every chart on the page recolours live for your heat limit 27°C
I'm comfortable up to 27°C feels-like
22° heat-averse 30° heat-loving

Default 27 °C is the upper edge of the Holiday Climate Index "ideal comfort" band (Scott, Rutty, Amelung & Tang, 2016). Above this, most warm-tourism travellers report measurable discomfort.

Saved to this browser. Changes update the strips below.
Recent · 2020-2024
Interest Google Trends 2021-2025 searches, not arrivals (?)
Day · avg daily high (?)
Night · avg overnight low (?)
UV index · On a typical day around midday, UV is about this (?)
234566765421
On the sunniest 1 in 10 days, UV reaches this — and even higher
357898873
PM2.5 air quality · on a typical day (?)
131610111317171511101113
On the worst 1 in 10 days, PM2.5 reaches this — and even higher
223217162029252216151725
May 9/10 feels 21°C · HCI 88/100
Day 23° · Night 12° 51% humidity 19 km/h wind 11 rain days (104h) 235h sun
Thermal 10
Sky 9
Rain 7
Wind 10

Higher = better, including rain & wind (green = "doesn't hurt the score", not "lots of it").

Compare with another destination

Add as many as you like — stacked below the main strips above. Each row is just the recent-window score strip and (for beach destinations) sea-temperature strip.

Tours in Philadelphia

17 top-rated tours via Viator. Booking links earn this site a commission at no cost to you. Map locations are approximate (centred on Philadelphia).

  1. 1Philadelphia Old City Historic Walking Tour with 10+ Top Sites4.91★ (2,165)1h 30mfrom $44🔥 Selling fast
  2. 2BYOB Historically Hilarious Trolley Tour of Philadelphia4.87★ (681)2hfrom $49🔥 Selling fast
  3. 3Most Charming Philadelphia Walking Tour | Society Hill + Old City5.00★ (1)1h 30mfrom $24🔥 Selling fast
  4. 4Flavors of Philly Food Tour4.79★ (527)2h 30mfrom $65🔥 Selling fast
  5. 5The Constitutional Walking Tour of Philadelphia4.69★ (912)1h 15mfrom $30🔥 Selling fast
  6. 6Badass Women's History Walking Tour of Philadelphia5.00★ (104)1h 45mfrom $59🔥 Selling fast
  7. 7True Crime Philadelphia and History Tour4.92★ (423)2h 30mfrom $44🔥 Selling fast
  8. 8Philly Gayborhood and LGBTQ History Walking Tour5.00★ (37)1h 30mfrom $59🔥 Selling fast
  9. 9Independence Mall (Entrance to 2 Historic Sites) 2.5 Hour Walking4.81★ (21)2h 30mfrom $39🔥 Selling fast
  10. 10Revolution and the Founders: History Tour of Philadelphia4.89★ (3,359)2hfrom $29
  11. 11Philadelphia 2 Hour Electric Cart Tour4.85★ (710)2hfrom $69
  12. 12Center City Philadelphia Food Tour with Reading Market4.87★ (977)2h 30mfrom $59
  13. 13Dark Philly Adult Night Tour4.91★ (4,385)2hfrom $38
  14. 142.5 Hour Philadelphia History Tour with Washington War Tent Show4.90★ (953)2h 30mfrom $45
  15. 15Behind The Scenes Food Tour: South Philly & Italian Market4.99★ (82)3hfrom $103🔥 Selling fast
  16. 16Small-Group Discovering Colonial Philadelphia Public Walking Tour5.00★ (2)2h 30mfrom $30
  17. 17Early Entry: Museum of the American Revolution Admission & 1-Hour Guided Tour4.04★ (23)1hfrom $60🔥 Selling fast

Last refreshed 2026-06-16.

Similar climatesWashington D.C.96% · New York City96% · Boston92%

Other destinations with the most-alike year-round climate to Philadelphia (apparent temperature, rain hours, sunshine — matched within the same trip-profile). The ±N chip compares each match's typical score for the current month against Philadelphia's. Based on the 2020-2024 climatology, not this year's actual weather.

Month-by-month

Month Temp °C Feels °C Rain days Rain h Rain h/day Humidity Wind km/h Sun h UV Interest Score
Jan -2–6 2 10 109 10.9 59% 20 138 2 Quiet 4
Feb -1–8 4 10 114 11.4 58% 20 144 3 Quiet 5
Mar 2–13 9 10 103 10.3 54% 22 182 4 Quiet 6
Apr 7–18 14 12 116 9.7 51% 22 204 5 Quiet 7
May 12–23 21 11 104 9.5 51% 19 235 6 Quiet 9
Jun 18–29 29 10 95 9.5 48% 18 260 6 Quiet 8
Jul 21–31 34 14 126 9.0 53% 17 271 7 Quiet 4
Aug 20–30 32 13 134 10.3 55% 17 244 6 Peak 5
Sep 16–26 26 10 104 10.4 56% 17 205 5 Busy 9
Oct 11–20 19 8 87 10.9 57% 17 189 4 Moderate 9
Nov 4–14 11 8 64 8.0 56% 19 175 2 Peak 7
Dec 0–8 4 10 106 10.6 63% 18 137 1 Busy 5

UV Index in Philadelphia by Month

UV index in Philadelphia peaks at 7 (high) in July, dropping to 1 (low) in December. June, July, August have high UV — SPF 30+ and sunglasses recommended.

Best months in detail

May

9/10

12–23°C (feels 21°C) · 11 rain days (104h) · 235 sun hours · 51% humidity · Quiet crowd · UV 6 (moderate) · sunniest 1 in 10 days reach 8 (high)

September

9/10

16–26°C · 10 rain days (104h) · 205 sun hours · 56% humidity · Busy crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 7 (high)

October

9/10

11–20°C (feels 19°C) · 8 rain days (87h) · 189 sun hours · 57% humidity · Moderate crowd · UV 4 (moderate)

Every month

Show the other 9 months in detail

January

4/10

-2–6°C (feels 2°C) · 10 rain days (109h) · 138 sun hours · 59% humidity · Quiet crowd · UV 2 (low)

February

5/10

-1–8°C (feels 4°C) · 10 rain days (114h) · 144 sun hours · 58% humidity · Quiet crowd · UV 3 (low) · sunniest 1 in 10 days reach 3 (moderate)

March

6/10

2–13°C (feels 9°C) · 10 rain days (103h) · 182 sun hours · 54% humidity · Quiet crowd · UV 4 (moderate) · sunniest 1 in 10 days reach 5 (moderate)

April

7/10

7–18°C (feels 14°C) · 12 rain days (116h) · 204 sun hours · 51% humidity · Quiet crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 7 (high)

June

8/10

18–29°C · 10 rain days (95h) · 260 sun hours · 48% humidity · Quiet crowd · UV 6 (high) · sunniest 1 in 10 days reach 9 (very high)

July

4/10

21–31°C (feels 34°C) · 14 rain days (126h) · 271 sun hours · 53% humidity · Quiet crowd · UV 7 (high) · sunniest 1 in 10 days reach 8 (very high)

August

5/10

20–30°C (feels 32°C) · 13 rain days (134h) · 244 sun hours · 55% humidity · Peak crowd · UV 6 (high) · sunniest 1 in 10 days reach 8 (high)

November

7/10

4–14°C (feels 11°C) · 8 rain days (64h) · 175 sun hours · 56% humidity · Peak crowd · UV 2 (low) · sunniest 1 in 10 days reach 3 (moderate)

December

5/10

0–8°C (feels 4°C) · 10 rain days (106h) · 137 sun hours · 63% humidity · Busy crowd · UV 1 (low)

Frequently asked questions about visiting Philadelphia

When is the best time to visit Philadelphia?

May is the highest-scoring month (9/10 on the Holiday Climate Index). Typical conditions: 12–23°C (11 rainy days). The top three months by score are May, September, October.

What is the worst time to visit Philadelphia?

July is the lowest-scoring month (4/10, capped by extreme heat). Typical conditions: 21–31°C (14 rainy days).

Is Philadelphia too hot in summer?

2 months (July, August) trip the heat deal-breaker in our scoring: apparent temperature crosses the comfort cap, so even with clear skies and low rain the score is held down. Plan around it if heat tolerance is low.

When are crowds lowest in Philadelphia?

Search-interest seasonality (Google Trends 2021-2025) is lowest in March and peaks in November. Interest tracks both in-trip visitors and lead-time planners, so treat it as a "destination is on people's minds" signal rather than literal arrivals.

Which months in Philadelphia have good weather but fewer tourists?

May (climate 9/10, crowd index 2) and October (climate 9/10, crowd index 48) — shoulder months with above-average climate and below-median search-interest. Often the best value-for-weather trade.

What is the UV index in Philadelphia by month?

UV peaks at 7 (high) in July and is lowest in December at 1 (low). Monthly peak values: Jan 2, Feb 3, Mar 4, Apr 5, May 6, Jun 6, Jul 7, Aug 6, Sep 5, Oct 4, Nov 2, Dec 1.

What is the UV index in Philadelphia in July?

July is the peak UV month in Philadelphia, with a daily-peak UV index of 7 (high). Apply SPF 30+, wear sunglasses, and seek shade during midday hours.

How high can UV get in Philadelphia on the sunniest days?

Most days look like the monthly average, but on the sunniest ~1 in 10 days UV climbs higher than the mean suggests. June is the worst case: typical days average UV 6 (high), but the top 10% of days reach UV 9 (very high) — and even higher. Months where the sunniest days routinely exceed the typical reading: February, March, April, May, June, July, August, September, November. Plan sun protection for the worst case, not the average.

Is air quality in Philadelphia bad for travelers?

PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 12 months: January, February, March, April, May, June, July, August, September, October, November, December. The worst month is June with a typical-day mean of 17 µg/m³ (unhealthy for sensitive); on the worst 10% of days PM2.5 reaches 29 µg/m³ (unhealthy) and higher. People with asthma, heart conditions, or sensitive children may want to avoid these months or limit outdoor activity. Source: CAMS via Open-Meteo.