Climate averages 1991–2020
Pittsburgh weather
in September.
A warm, wet month: the 4th warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Pittsburgh: daytime highs average 23.9°C and nights cool to about 14.4°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 101 mm of rain on roughly 10 days, which makes September a wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 30 min on an average September day.
The nearest other city in this atlas is Canton (Ohio), United States (123 km away). In September its highs average 23.1°C, 0.8°C cooler than Pittsburgh, with 87 mm of rain.
Among the 498 cities listed in the United States, Pittsburgh ranks joint 361st of 498 for the warmest September highs and joint 398th of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Pittsburgh is 3.0°C cooler than that mean.
From September to October, average highs fall by 6.6°C to 17.4°C, and monthly rainfall falls from 101 mm to 93 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Pittsburgh climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 2.8°C-5.5°C | -5.5°C | 92 | 12.0 | 9.610 h |
| February | 4.8°C-4.7°C | -4.7°C | 80 | 10.9 | 10.611 h |
| March | 9.9°C-0.5°C | -0.5°C | 108 | 12.9 | 11.912 h |
| April | 16.6°C5.5°C | 5.5°C | 119 | 13.8 | 13.313 h |
| May | 21.6°C11.3°C | 11.3°C | 123 | 14.3 | 14.414 h |
| June | 26.0°C16.2°C | 16.2°C | 126 | 13.6 | 15.015 h |
| July | 28.2°C18.6°C | 18.6°C | 116 | 14.0 | 14.815 h |
| August | 27.5°C17.9°C | 17.9°C | 93 | 11.9 | 13.814 h |
| September, selected | 23.9°C14.4°C | 14.4°C | 101 | 10.4 | 12.513 h |
| October | 17.4°C8.4°C | 8.4°C | 93 | 10.7 | 11.211 h |
| November | 10.6°C2.6°C | 2.6°C | 88 | 10.0 | 10.010 h |
| December | 5.1°C-2.1°C | -2.1°C | 89 | 11.6 | 9.39 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Canton (Ohio), United States in SeptemberUnited States · 123 kmHigh 23.1°C · Low 14.0°C · 87 mm rain
- Akron in SeptemberUnited States · 147 kmHigh 23.0°C · Low 14.0°C · 88 mm rain
- Parma, United States in SeptemberUnited States · 180 kmHigh 22.5°C · Low 14.8°C · 85 mm rain
- Cleveland in SeptemberUnited States · 185 kmHigh 22.4°C · Low 15.2°C · 85 mm rain
- Erie in SeptemberUnited States · 188 kmHigh 21.2°C · Low 15.6°C · 106 mm rain
- Columbus in SeptemberUnited States · 261 kmHigh 24.3°C · Low 14.6°C · 73 mm rain
- Germantown in SeptemberUnited States · 272 kmHigh 25.1°C · Low 16.0°C · 113 mm rain
- Centreville in SeptemberUnited States · 283 kmHigh 25.3°C · Low 16.8°C · 111 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Pittsburgh) is explained once on the Pittsburgh year overview and on the Sources, method and limits page.