West Mifflin weather in December: West Mifflin, Pennsylvania: normal highs, lows, rain and records for December
West Mifflin in December has a normal high of 41°F and a normal low of 28°F, a daily mean of 34°F, falling from 45°F on the 1st to 38°F by the 31st. Measurable precipitation falls on 14 days in a normal December, 3.04 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 5°C and low of −2°C, 77 mm of precipitation in December.
- 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 December?
The normal high is 41°F and the normal low 28°F, for a daily mean of 34.4°F. December is 8.8°F cooler than November and 4.9°F warmer than January. December is the 10th warmest month of the year in West Mifflin and the 10th wettest. Across the month the normal high falls 7°F, from 45°F on December 1 to 38°F on December 31. From one year to the next December's mean temperature typically moves about 4.6°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 30°F and 39°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 46%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 45°F | 31°F | 45% | 24% |
| December 8 | 43°F | 30°F | 46% | 24% |
| December 15 | 41°F | 28°F | 46% | 23% |
| December 22 | 39°F | 26°F | 46% | 22% |
| December 31 | 38°F | 24°F | 45% | 21% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 45°F | 31°F | 45% | 24% | 9 h 30 min |
| December 2 | 45°F | 31°F | 45% | 24% | 9 h 30 min |
| December 3 | 45°F | 31°F | 45% | 24% | 9 h 30 min |
| December 4 | 44°F | 31°F | 45% | 24% | 9 h 30 min |
| December 5 | 44°F | 30°F | 46% | 24% | 9 h 30 min |
| December 6 | 44°F | 30°F | 46% | 24% | 9 h 30 min |
| December 7 | 43°F | 30°F | 46% | 24% | 9 h 30 min |
| December 8 | 43°F | 30°F | 46% | 24% | 9 h 20 min |
| December 9 | 43°F | 29°F | 46% | 24% | 9 h 20 min |
| December 10 | 42°F | 29°F | 46% | 24% | 9 h 20 min |
| December 11 | 42°F | 29°F | 46% | 24% | 9 h 20 min |
| December 12 | 42°F | 29°F | 46% | 24% | 9 h 20 min |
| December 13 | 42°F | 28°F | 46% | 24% | 9 h 20 min |
| December 14 | 41°F | 28°F | 46% | 24% | 9 h 20 min |
| December 15 | 41°F | 28°F | 46% | 23% | 9 h 20 min |
| December 16 | 41°F | 28°F | 46% | 23% | 9 h 20 min |
| December 17 | 41°F | 27°F | 46% | 23% | 9 h 20 min |
| December 18 | 40°F | 27°F | 46% | 23% | 9 h 20 min |
| December 19 | 40°F | 27°F | 46% | 23% | 9 h 20 min |
| December 20 | 40°F | 27°F | 46% | 23% | 9 h 20 min |
| December 21 | 40°F | 27°F | 46% | 23% | 9 h 20 min |
| December 22 | 39°F | 26°F | 46% | 22% | 9 h 20 min |
| December 23 | 39°F | 26°F | 46% | 22% | 9 h 20 min |
| December 24 | 39°F | 26°F | 46% | 22% | 9 h 20 min |
| December 25 | 39°F | 26°F | 46% | 22% | 9 h 20 min |
| December 26 | 39°F | 25°F | 46% | 22% | 9 h 20 min |
| December 27 | 38°F | 25°F | 46% | 22% | 9 h 20 min |
| December 28 | 38°F | 25°F | 46% | 22% | 9 h 20 min |
| December 29 | 38°F | 25°F | 45% | 21% | 9 h 20 min |
| December 30 | 38°F | 25°F | 45% | 21% | 9 h 20 min |
| December 31 | 38°F | 24°F | 45% | 21% | 9 h 20 min |
- Normal high
- 41°FDecember average
- Normal low
- 28°FDecember average
- Precipitation
- 3.04 inmonth total
- Days with precipitation
- 140.01 inch or more
- Nights at 32°F or colder
- 23
- Daylight
- 9 h 30 min to 9 h 20 minDecember 1 to December 31
- Sunshine
- 51%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 December?
On a given December day the chance of 0.01 inch or more is 46% on average, highest around December 16 (46%). In all, 3.04 in falls on 14 days of a normal December.
In a normal December in West Mifflin, 23 nights fall to freezing and 8 days stay below freezing all day.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014762.
How humid and windy is West Mifflin in December?
At 3 p.m. the normal temperature is 36°F with 64% relative humidity and a dew point of 24°F; at 6 a.m. it is 29°F with 78% humidity. The wind averages 9.3 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. | 29°F | 23°F | 78% | 8.8 mph | – |
| 9 a.m. | 30°F | 24°F | 77% | 9.1 mph | 26% |
| noon | 34°F | 24°F | 68% | 10.7 mph | – |
| 3 p.m. | 36°F | 24°F | 64% | 10.5 mph | 31% |
| 6 p.m. | 34°F | 24°F | 68% | 8.9 mph | 33% |
| 9 p.m. | 32°F | 24°F | 71% | 8.9 mph | 37% |
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 December in West Mifflin?
The warmest December temperature on this station's record (since 1935) is 73°F, on December 5, 2001; the coldest is −5°F, on December 26, 1935. The wettest December brought 6.31 in (2008); the snowiest, 26.0 inches (1944).
The December mean against the 1991-2020 normal of 34.4°F: 2021 42.6°F (+8.2), 2022 35.7°F (+1.3), 2023 42.7°F (+8.3), 2024 36.2°F (+1.8), 2025 31.1°F (−3.3). 4 of 5 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 42.6°F | +8.2°F | 4.23 in |
| 2022 | 35.7°F | +1.3°F | 1.95 in |
| 2023 | 42.7°F | +8.3°F | 2.06 in |
| 2024 | 36.2°F | +1.8°F | 2.39 in |
| 2025 | 31.1°F | −3.3°F | 1.47 in |
Source: records: ACIS, station USW00014762; recent months: ACIS, station USW00014762. Records and recent months use complete months only.
How does December in West Mifflin compare across Pennsylvania?
Across the 108 places PlainClimate covers in Pennsylvania, December normal highs run from 34°F in Laporte to 48°F in Marcus Hook; West Mifflin's is 41°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- West Mifflin in November51°F by day, 35°F at night
- West Mifflin in January37°F by day, 22°F at night
- West Mifflin through the yearEvery month, frost dates, records and recent years
- Pennsylvania in DecemberThe statewide normal and the warmest and coolest places
- Marcus Hook: Pennsylvania's warmest Decembernormal high 48°F