Weather in Pittsburgh in May

A good month. May works. It is not the peak, but nothing about it fights you. You should expect rain on 15 days of the month, which is more days wet than dry.

May ranks 3 of 12 in Pittsburgh. Only September scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain on 15 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest May day reached 35 °C and the coldest night fell to -4.5 °C, and the wettest single day dropped 28 mm — roughly 30% of the month's rain in one day.

May is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest May on record still delivered 138 mm against 47 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 94 mm average is a reasonable planning figure, not a promise.

Wind is light at 0.6 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 78%, high enough to notice on the warm days without dominating them.

How May sits in the year

The month is on the way up: 5.4 °C warmer than April, and June adds another 4.3 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in May

May is at or near the longest days of Pittsburgh's year: 14.4 hours of daylight, gaining 0.9 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 — 36.1 °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.

May in Pittsburgh versus nearby

If Pittsburgh is one option among several, the nearby comparison is worth making. Cleveland is the weaker option in May — 5.2 °C cooler, 1 day more rain. Columbus is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: May works, with September the better month by 9 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Pittsburgh

See all twelve months in Pittsburgh, or where else to go in May.