Philadelphia weather in May
Temperature, sea and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Good
Best time to visit: April – June, August – October
What is the weather like in Philadelphia in May?
In May, Philadelphia is warm: daytime highs average 22 °C, and nights cool down to about 12 °C. The sea averages 14.6 °C – swimming is only for the hardy. The sun shines for around 7 hours a day. Rain is frequent, with about 11 rainy days and 90 mm in total. All in all, May is a good month for a holiday in Philadelphia.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 14 h 21 min05:46 – 20:07
- UV index
- 9 · very highclear sky, noon (estimate)All months
- Muggy days
- 2 daysdew point 18 °C or moreAll months
- Wind
- 17 km/haverage daily peakAll months
- Cloud cover
- 62 %on averageAll months
- Hot days
- 2 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC−4America/New_York
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %62 %
- Few rainy daysweight 30 %49 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in May
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
- Rain jacket or umbrella
Philadelphia in May: quick answers
Is Philadelphia hot in May?
Warm rather than hot: in May, daytime highs in Philadelphia average 22 °C and nights cool to about 12 °C. On about 2 days the thermometer climbs to 30 °C or more.
Can you swim in Philadelphia in May?
Only if you don't mind cold water: in May the sea averages just 14.6 °C. Comfortable swimming is possible from June to September.
Does it rain much in Philadelphia in May?
Rain is frequent, with about 11 rainy days and 90 mm in total.
Philadelphia month by month
The whole year in PhiladelphiaAll destinations: USAWhere to go in MaySea temperature in May
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences