Weather in Philadelphia in July

Shoulder season. July is shoulder season in Philadelphia — cheaper, quieter, and a genuine gamble. Highs average 30 °C, lows 19.6 °C, and rain falls on 14 days — nothing in the month is working against you.

July ranks 8 of 12 in Philadelphia: past the worst of the year but short of September, which is the month to book if the dates are open.

This is wet-season rain: 14 wet days and 5 genuinely heavy ones, which in this climate means concentrated downpours rather than all-day grey. The pattern is usually a clear morning and a loud afternoon, so front-load the day and stop fighting the 3pm hour. Pack for 30 °C days and 19.6 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 15 days top 30 °C — hot spells arrive, but they break. Across the twenty years measured, the hottest July day reached 39.1 °C and the coldest night fell to 10.9 °C, and the wettest single day dropped 81 mm — roughly 65% of the month's rain in one day.

July is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest July on record still delivered 202 mm against 37 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 124 mm average is a reasonable planning figure, not a promise.

Wind is light at 5.3 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 75%, high enough to notice on the warm days without dominating them.

How July sits in the year

Temperatures hold steady either side: 26.9 °C in June, 30 here, 29.6 in August. Nothing about the timing within the month matters much.

Daylight in July

July is at or near the longest days of Philadelphia's year: 14.8 hours of daylight, losing 0.6 hours across the month. Evenings are the real gain — dinner outdoors still happens in full light.

An inland climate

With no coast nearby, the year swings a fair way — 34.9 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

July in Philadelphia versus nearby

If Philadelphia is one option among several, the nearby comparison is worth making. New York City is a better bet in July — 3.8 °C cooler, 1 day less rain. Washington is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: July is a compromise. September is 24 points better and is what Philadelphia is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Philadelphia

See all twelve months in Philadelphia, or where else to go in July.