West Mifflin weather in May: West Mifflin, Pennsylvania: normal highs, lows, rain and records for May
West Mifflin in May has a normal high of 72°F and a normal low of 52°F, a daily mean of 62°F, rising from 68°F on the 1st to 75°F by the 31st. Measurable precipitation falls on 15 days in a normal May, 4.08 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 22°C and low of 11°C, 104 mm of precipitation in May.
- 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 May?
The normal high is 72°F and the normal low 52°F, for a daily mean of 61.8°F. May is 9.7°F warmer than April and 7.7°F cooler than June. May is the 5th warmest month of the year in West Mifflin and the 2nd wettest. Across the month the normal high rises 7°F, from 68°F on May 1 to 75°F on May 31. From one year to the next May's mean temperature typically moves about 3.5°F either way (NOAA's standard deviation), so roughly two Mays in three average between 58°F and 65°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 50%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| May 1 | 68°F | 47°F | 48% | 30% |
| May 8 | 70°F | 50°F | 49% | 30% |
| May 15 | 72°F | 52°F | 50% | 30% |
| May 22 | 73°F | 54°F | 49% | 29% |
| May 31 | 75°F | 56°F | 48% | 29% |
Every day of May: normal high, low and chance of precipitation (warmest afternoon May 31, coldest night May 1)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| May 1 | 68°F | 47°F | 48% | 30% | 13 h 50 min |
| May 2 | 69°F | 48°F | 48% | 30% | 14 h |
| May 3 | 69°F | 48°F | 48% | 30% | 14 h |
| May 4 | 69°F | 48°F | 49% | 30% | 14 h |
| May 5 | 69°F | 49°F | 49% | 30% | 14 h |
| May 6 | 70°F | 49°F | 49% | 30% | 14 h |
| May 7 | 70°F | 49°F | 49% | 30% | 14 h 10 min |
| May 8 | 70°F | 50°F | 49% | 30% | 14 h 10 min |
| May 9 | 70°F | 50°F | 49% | 30% | 14 h 10 min |
| May 10 | 71°F | 50°F | 49% | 30% | 14 h 10 min |
| May 11 | 71°F | 51°F | 50% | 30% | 14 h 20 min |
| May 12 | 71°F | 51°F | 50% | 30% | 14 h 20 min |
| May 13 | 71°F | 51°F | 50% | 30% | 14 h 20 min |
| May 14 | 72°F | 51°F | 50% | 30% | 14 h 20 min |
| May 15 | 72°F | 52°F | 50% | 30% | 14 h 20 min |
| May 16 | 72°F | 52°F | 50% | 30% | 14 h 30 min |
| May 17 | 72°F | 52°F | 50% | 30% | 14 h 30 min |
| May 18 | 72°F | 52°F | 49% | 30% | 14 h 30 min |
| May 19 | 73°F | 53°F | 49% | 30% | 14 h 30 min |
| May 20 | 73°F | 53°F | 49% | 29% | 14 h 30 min |
| May 21 | 73°F | 53°F | 49% | 29% | 14 h 30 min |
| May 22 | 73°F | 54°F | 49% | 29% | 14 h 40 min |
| May 23 | 73°F | 54°F | 49% | 29% | 14 h 40 min |
| May 24 | 74°F | 54°F | 48% | 29% | 14 h 40 min |
| May 25 | 74°F | 54°F | 48% | 29% | 14 h 40 min |
| May 26 | 74°F | 55°F | 48% | 29% | 14 h 40 min |
| May 27 | 74°F | 55°F | 48% | 29% | 14 h 40 min |
| May 28 | 75°F | 55°F | 48% | 29% | 14 h 50 min |
| May 29 | 75°F | 55°F | 48% | 29% | 14 h 50 min |
| May 30 | 75°F | 56°F | 48% | 29% | 14 h 50 min |
| May 31 | 75°F | 56°F | 48% | 29% | 14 h 50 min |
- Normal high
- 72°FMay average
- Normal low
- 52°FMay average
- Precipitation
- 4.08 inmonth total
- Days with precipitation
- 150.01 inch or more
- Daylight
- 13 h 50 min to 14 h 50 minMay 1 to May 31
- Days at 70°F or more
- 20
- Days at 80°F or more
- 8
- Sunshine
- 69%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 May?
On a given May day the chance of 0.01 inch or more is 49% on average, highest around May 13 (50%). In all, 4.08 in falls on 15 days of a normal May, 1 of them with an inch or more.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014762.
How humid and windy is West Mifflin in May?
At 3 p.m. the normal temperature is 73°F with 52% relative humidity and a dew point of 54°F; at 6 a.m. it is 58°F with 85% humidity. The wind averages 7.2 mph, most often from the west-southwest in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 58°F | 54°F | 85% | 5.9 mph | 49% |
| 9 a.m. | 66°F | 55°F | 69% | 7.2 mph | 46% |
| noon | 71°F | 55°F | 56% | 8.6 mph | 34% |
| 3 p.m. | 73°F | 54°F | 52% | 9.2 mph | 35% |
| 6 p.m. | 71°F | 54°F | 55% | 8.3 mph | 45% |
| 9 p.m. | 66°F | 54°F | 65% | 6.3 mph | 53% |
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 May in West Mifflin?
The warmest May temperature on this station's record (since 1935) is 93°F, on May 1, 1942; the coldest is 28°F, on May 9, 2020. The wettest May brought 6.51 in (2025).
The May mean against the 1991-2020 normal of 61.8°F: 2021 60.0°F (−1.8), 2022 64.4°F (+2.6), 2023 60.9°F (−0.9), 2024 66.9°F (+5.1), 2025 60.1°F (−1.7), 2026 59.0°F (−2.8). 2 of 6 ran warmer than normal.
| May | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 60.0°F | −1.8°F | 3.18 in |
| 2022 | 64.4°F | +2.6°F | 5.76 in |
| 2023 | 60.9°F | −0.9°F | 2.00 in |
| 2024 | 66.9°F | +5.1°F | 5.29 in |
| 2025 | 60.1°F | −1.7°F | 6.51 in |
| 2026 | 59.0°F | −2.8°F | 3.62 in |
Source: records: ACIS, station USW00014762; recent months: ACIS, station USW00014762. Records and recent months use complete months only.
How does May in West Mifflin compare across Pennsylvania?
Across the 108 places PlainClimate covers in Pennsylvania, May normal highs run from 65°F in Laporte to 75°F in Phoenixville; West Mifflin's is 72°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- West Mifflin in April63°F by day, 42°F at night
- West Mifflin in June79°F by day, 60°F at night
- West Mifflin through the yearEvery month, frost dates, records and recent years
- Pennsylvania in MayThe statewide normal and the warmest and coolest places
- Phoenixville: Pennsylvania's warmest Maynormal high 75°F