Pittsburgh, PA weather in September
In September, Pittsburgh sees highs around 75°F and lows around 55°F: mild, with some rain. There are about 10 days with rain. Good for outdoor plans.
- Normal high
- 75°F
- Normal low
- 55°F
- Wet days
- 10
- 3.3 in total
- Muggy days
- 3
- dew point 65°F+
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 80°F | 70°F |
| Normal low | 60°F | 50°F |
| Chance of a wet day | 31% | 34% |
| Sunrise / sunset | 6:47 am / 7:52 pm | 7:15 am / 7:04 pm |
| Daylight | 13.1 h | 11.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Eastern Time).
A typical September day
- 6 am58°Fdew point 55°F
- 9 am64°Fdew point 56°F
- Noon71°Fdew point 56°F
- 3 pm73°Fdew point 55°F
- 6 pm70°Fdew point 55°F
- 9 pm65°Fdew point 55°F
NOAA hourly normals (local standard time) from Pittsburgh Allegheny Co Airport (7 mi away); average wind 6 mph; clear or few clouds in 46% of daytime hours, mostly cloudy or overcast in 43%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F15 of 30
- Hot dayshigh 90°F or more1 of 30
- Muggy daysdaily mean dew point 65°F or more3 of 30
- Wet daysat least 0.01 in of rain or melted snow10 of 30
- Notable rainat least 0.10 in6 of 30
- Freezing nightslow 32°F or below0 of 30
- Snow on the groundsnow depth 1 in or more0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 3.3 in; a dry September brings about 2.0 in and a wet one about 3.7 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more.
How September varies from year to year
- Warmest September, 1991-20202016: average high 80°F
- Coolest September2006: average high 69°F
- Wettest September2004: 10.1 in
- Driest September2017: 0.6 in
- Highest reading95°F (September 4, 2018)
- Lowest reading35°F (September 29, 2000)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 82°F | 75°F | 63°F |
| Normal low | 62°F | 55°F | 44°F |
| Wet days | 11 | 10 | 11 |
| Comfortable days | 8 | 15 | 12 |
| Daylight | 13.7 h | 12.4 h | 11.1 h |
Highs change by -7°F from August and -12°F into October.
Nearby alternatives in September
- Warmer: Washington, DC190 mi · high 81°F · 9 wet days
How Pittsburgh ranks in September
- Normal high282nd warmest of 378 cities; 4th of 4 in Pennsylvania
- Wet days301st driest of 378
- Comfortable days88th most of 342
What to pack for Pittsburgh in September
- A rain jacket or umbrella – rain on about 10 days
Heating and cooling
September has 86 heating degree days and 85 cooling degree days (base 65°F), 3% of the year's total heating and cooling demand.
Questions
How hot is Pittsburgh in September?
The normal high is 75°F and the normal low is 55°F. From 1991 to 2020 the hottest September reading was 95°F (most recently on September 4, 2018).
Does it rain a lot in Pittsburgh in September?
About 10 days in September have at least 0.01 in of precipitation, and the normal total is 3.3 in. The wettest September in 1991-2020 was in 2004 (10.1 in); the driest was in 2017 (0.6 in).
Is September a good time to visit Pittsburgh?
September ranks 2nd of 12 months on our comfort score for Pittsburgh (68 out of 100). It has about 15 comfortable days and about 1 day at 90°F or hotter. The best months are May and September.
Where the numbers come from
- Temperature, rain, snowfall and snow depth: Pittsburgh Intl Airport (USW00094823), 12 mi WNW of the city center, 1,203 ft (438 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Frost dates: Emsworth L/D Ohio Rvr (USC00362574), 6.6 mi NW of the city center, 717 ft . NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: Pittsburgh Allegheny Co Airport (USW00014762), 7.1 mi SSE of the city center, 1,248 ft (483 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Pittsburgh International Airport (725200-94823), 12 mi WNW of the city center, 1,119 ft (354 ft higher than the city). Hourly observations, 1991-2020.