West Mifflin weather in September: West Mifflin, Pennsylvania: normal highs, lows, rain and records for September
West Mifflin in September has a normal high of 75°F and a normal low of 56°F, a daily mean of 65°F, falling from 79°F on the 1st to 70°F by the 30th. Measurable precipitation falls on 12 days in a normal September, 3.54 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 24°C and low of 13°C, 90 mm of precipitation in September.
- NOAA stationPittsburgh Allegheny County Airport
- Station IDUSW00014762
- Location40.35°N 79.92°W
- Elevation1,248 ft (380 m)
- From the centerunder 1 mile
- Population18,902
- Jan 37° 22°
- Feb 40° 24°
- Mar 49° 31°
- Apr 63° 42°
- May 72° 52°
- Jun 79° 60°
- Jul 83° 64°
- Aug 81° 63°
- Sep 75° 56°
- Oct 63° 45°
- Nov 51° 35°
- Dec 41° 28°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is West Mifflin in September?
The normal high is 75°F and the normal low 56°F, for a daily mean of 65.4°F. September is 6.7°F cooler than August and 11.2°F warmer than October. September is the 4th warmest month of the year in West Mifflin and the 5th wettest. Across the month the normal high falls 9°F, from 79°F on September 1 to 70°F on September 30. From one year to the next September's mean temperature typically moves about 2.4°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 63°F and 68°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 43%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 79°F | 60°F | 37% | 21% |
| September 8 | 77°F | 58°F | 37% | 20% |
| September 15 | 75°F | 56°F | 38% | 20% |
| September 22 | 73°F | 54°F | 40% | 20% |
| September 30 | 70°F | 51°F | 43% | 22% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 79°F | 60°F | 37% | 21% | 13 h 10 min |
| September 2 | 79°F | 60°F | 37% | 21% | 13 h 10 min |
| September 3 | 79°F | 60°F | 37% | 20% | 13 h |
| September 4 | 79°F | 60°F | 37% | 20% | 13 h |
| September 5 | 78°F | 59°F | 37% | 20% | 13 h |
| September 6 | 78°F | 59°F | 37% | 20% | 12 h 50 min |
| September 7 | 78°F | 59°F | 37% | 20% | 12 h 50 min |
| September 8 | 77°F | 58°F | 37% | 20% | 12 h 50 min |
| September 9 | 77°F | 58°F | 37% | 20% | 12 h 50 min |
| September 10 | 77°F | 58°F | 38% | 20% | 12 h 40 min |
| September 11 | 77°F | 58°F | 38% | 20% | 12 h 40 min |
| September 12 | 76°F | 57°F | 38% | 20% | 12 h 40 min |
| September 13 | 76°F | 57°F | 38% | 20% | 12 h 40 min |
| September 14 | 76°F | 57°F | 38% | 20% | 12 h 30 min |
| September 15 | 75°F | 56°F | 38% | 20% | 12 h 30 min |
| September 16 | 75°F | 56°F | 39% | 20% | 12 h 30 min |
| September 17 | 75°F | 56°F | 39% | 20% | 12 h 30 min |
| September 18 | 74°F | 55°F | 39% | 20% | 12 h 20 min |
| September 19 | 74°F | 55°F | 39% | 20% | 12 h 20 min |
| September 20 | 73°F | 55°F | 40% | 20% | 12 h 20 min |
| September 21 | 73°F | 54°F | 40% | 20% | 12 h 20 min |
| September 22 | 73°F | 54°F | 40% | 20% | 12 h 10 min |
| September 23 | 72°F | 54°F | 41% | 20% | 12 h 10 min |
| September 24 | 72°F | 53°F | 41% | 21% | 12 h 10 min |
| September 25 | 72°F | 53°F | 41% | 21% | 12 h 10 min |
| September 26 | 71°F | 52°F | 42% | 21% | 12 h |
| September 27 | 71°F | 52°F | 42% | 21% | 12 h |
| September 28 | 70°F | 52°F | 43% | 22% | 12 h |
| September 29 | 70°F | 51°F | 43% | 22% | 11 h 50 min |
| September 30 | 70°F | 51°F | 43% | 22% | 11 h 50 min |
- Normal high
- 75°FSeptember average
- Normal low
- 56°FSeptember average
- Precipitation
- 3.54 inmonth total
- Days with precipitation
- 120.01 inch or more
- Days at 90°F or more
- 1
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 23
- Days at 80°F or more
- 10
- Sunshine
- 75%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00014762; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in West Mifflin in September?
On a given September day the chance of 0.01 inch or more is 39% on average, highest around September 30 (43%). In all, 3.54 in falls on 12 days of a normal September, 1 of them with an inch or more.
In a normal September in West Mifflin, 1 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014762.
How humid and windy is West Mifflin in September?
At 3 p.m. the normal temperature is 68°F with 52% relative humidity and a dew point of 50°F; at 6 a.m. it is 53°F with 87% humidity. The wind averages 7.0 mph, most often from the west-southwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 53°F | 49°F | 87% | 6.2 mph | 56% |
| 9 a.m. | 58°F | 51°F | 76% | 7.3 mph | 54% |
| noon | 66°F | 50°F | 58% | 8.6 mph | 47% |
| 3 p.m. | 68°F | 50°F | 52% | 8.6 mph | 44% |
| 6 p.m. | 64°F | 50°F | 59% | 6.5 mph | 57% |
| 9 p.m. | 60°F | 50°F | 71% | 6.3 mph | 62% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014762. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in West Mifflin?
The warmest September temperature on this station's record (since 1935) is 95°F, on September 8, 1939; the coldest is 34°F, on September 28, 1942. The wettest September brought 11.89 in (2018).
The September mean against the 1991-2020 normal of 65.4°F: 2021 66.8°F (+1.4), 2022 65.6°F (+0.2), 2023 67.1°F (+1.7), 2024 69.7°F (+4.3), 2026 67.7°F (+2.3). 5 of 5 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 66.8°F | +1.4°F | 4.35 in |
| 2022 | 65.6°F | +0.2°F | 2.51 in |
| 2023 | 67.1°F | +1.7°F | 1.01 in |
| 2024 | 69.7°F | +4.3°F | 2.01 in |
| 2026 | 67.7°F | +2.3°F | 4.73 in |
Source: records: ACIS, station USW00014762; recent months: ACIS, station USW00014762. Records and recent months use complete months only.
How does September in West Mifflin compare across Pennsylvania?
Across the 108 places PlainClimate covers in Pennsylvania, September normal highs run from 68°F in Laporte to 80°F in Marcus Hook; West Mifflin's is 75°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- West Mifflin in August81°F by day, 63°F at night
- West Mifflin in October63°F by day, 45°F at night
- West Mifflin through the yearEvery month, frost dates, records and recent years
- Pennsylvania in SeptemberThe statewide normal and the warmest and coolest places
- Marcus Hook: Pennsylvania's warmest Septembernormal high 80°F