Pittsburgh weather by month
The best time to visit Pittsburgh is May, June and September — 89/100 in September, 26°C and 8 rainy days. The best season is summer, June to August (79/100 on average).
The worst month is January at 43/100 — freezing, rainy, clean air. See January →
Updated September 2026 · climate normals from ERA5 reanalysis
Planning the wider trip? Best time to visit United States →
Best season: June to August (79/100 on average) · worst January (43/100)
- Days
- 26°C
- Nights
- 14°C
- Wet days
- 8
- Sun
- 9.1 h
- Humidity
- 75%
- Daylight
- 12 h

Pittsburgh, month by month
Comfort score out of 100 for the kind of trip Pittsburgh is best for, the average high, rainy days and hours of sun a day from the climate normals, and how busy it tends to be.
What's on in Pittsburgh through the year
Festivals, natural spectacles, holidays and the seasons to watch out for — curated and sourced. The month pages carry the detail.
- February
- Lenten fish fries4 Feb – 23 Apr (usually)Festival
- May
- Pittsburgh Marathon1–10 May (usually)Festival
- June
- Three Rivers Arts Festival5–15 Jun (usually)Festival
- July
- Vintage Grand Prix10–20 Jul (usually)Festival
- Picklesburgh16–20 Jul (usually)Festival
- Steelers training camp24 Jul – 20 Aug (usually)Festival
- Independence Day3–5 JulHoliday
- September
- Pittsburgh Irish Festival7–16 Sep (usually)Festival
- October
- Fall colour8 Oct – 2 Nov (usually)Nature
- November
- Light Up Night and holiday market18 Nov – 23 Dec (usually)Festival
- Thanksgiving25–29 NovHoliday
- The Rink at PPG Place14 Nov – 1 Mar (usually)Opening
Crowds in Pittsburgh in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsPittsburgh Irish Festival, Summer break in United States(estimated)
Peak crowdsBusyShoulder seasonQuiet
Traveller notes on Pittsburgh
What people who have been say about the place — the year-round notes first, then month by month.
Pittsburgh forum threads describe January as genuinely unpredictable, with typical temperatures cited between 20 and 40F but posters clear that any given day could bring snow, rain, or bright, unusually warm sun instead. The consistent theme across threads was variability rather than a single dominant pattern - cold and wet or snowy conditions were called typical, but posters were careful to note real warm spells and clear stretches happen too. The standard advice was to dress in real layers, since it's far easier to peel off a layer that turns out unnecessary than to be caught without enough warmth if the day runs colder than expected.
Asked what March is like, a local gave the most honest answer on any thread in this collection: "well, it's not our finest month, and that's one reason that flight was cheap." The forecast is "variable — could be nice, could be snowing," and the advice is simply not to pack summer clothes. One useful calibration for European visitors: a poster comparing Pittsburgh's March with Ireland's found it "only a few degrees colder at minimum, and around the same for the maximum," so this is damp-and-changeable rather than a hard continental winter. Our record fits that: 11.8°C days against 1.6°C nights, 12.6 rain days and 6.1cm of snow — enough snow to be possible on any given day, not enough to define the month.
Pittsburgh-forum threads on May weather describe genuine spring: T-shirt days with a light jacket or hoodie for the evenings, frosts finally behind for the year, and the occasional 80-degree Fahrenheit afternoon that posters say is really borrowing from June rather than typical May. The standing advice is to pack long pants plus that light layer and check the forecast close to the trip, since the month runs changeable rather than settled. Rain shows up on close to half the days by some counts, which the record backs: 22.5C days, 10.4C nights, 109mm of rain across nearly twelve days and 9.8 hours of sun - spring here means real rain, not just the odd shower.
June is where the year changes character here, and regulars describe both ends of it: cool sunny days and all-day spring rain at the start, hazy humid ones with short thunderstorms by the finish. Highs can be anywhere from the sixties to the nineties, with the upper seventies and low eighties likeliest - our row gives 27.5C reading as 29C over 14.7C nights. June is also the month most likely to produce a whole day of rain rather than a burst, and our 98.5mm across 9.1 days carries both patterns. The cloud and humidity keep the days from swinging much, so the heat that builds tends to linger. The record: 10.9 hours of sun and AQI 67.
August is the driest month of the summer here on the board's own reckoning, which is a relative claim: our row still carries 88mm across 9.3 days, arriving as the short heavy thunderstorms they say July and August specialise in. The other local observation is that the cloud and the humidity keep the temperature from swinging, so a hot day stays hot and a cool one stays cool; our 29C reads as 31C at 76 percent humidity, over 17C nights. The rivers are what the city does with a summer evening - the trails along them and the boats on them. Sun is generous at 10.7 hours inside 13.7 of daylight. The record: a dew point of 17.6C and AQI 58.
Pittsburgh's forum calls September, alongside October, the nicest stretch of the year — mid-70s to 80s by day, cool enough for a light sweater by evening. Regulars still note the odd genuinely hot day can turn up even this late in summer, so packing only for mild weather is a mistake.
Regulars are candid this month resists easy prediction, warning visitors to be ready for rain, snow, and unexpected warm, sunny days all as real possibilities - snow as early as October has happened, even if it's not the norm. Our row backs the cooling, changeable read, 19.5C over 7.5C nights feeling 6C, with 87.2mm of rain across 9.5 days. Regulars are consistent this stretch into November is genuinely tricky weather-wise, with locals themselves saying they never really know what a given week will bring, so layering plus a real rain jacket beats trusting a single forecast. The record: humidity 74 percent, 7.2 hours of sun, a 15.1 kph wind and one of the cleanest air readings in this project, AQI 35.
Add your own note from Pittsburgh's card on the map.