Upper St. Clair, PA climate
Upper St. Clair has chilly, snowy winters and warm summers. A typical July afternoon reaches 84°, a January night drops to 22°, and about 44 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Upper St. Clair feels like
Winter
Spring
Summer
Fall
Upper St. Clair weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 38° | 22° | 3.0" | 13.3" | 17 | 14 | 22° – 39° |
| February | 41° | 24° | 2.5" | 11.7" | 14 | 11 | 19° – 41° |
| March | 50° | 31° | 3.3" | 7.6" | 14 | 5 | 34° – 52° |
| April | 64° | 40° | 3.4" | 1.0" | 14 | 0 | 46° – 57° |
| May | 73° | 50° | 4.0" | 0 | 14 | 0 | 55° – 68° |
| June | 81° | 59° | 4.2" | 0 | 12 | 0 | 66° – 72° |
| July | 84° | 63° | 4.2" | 0 | 11 | 0 | 69° – 78° |
| August | 83° | 62° | 3.6" | 0 | 11 | 0 | 68° – 77° |
| September | 77° | 55° | 3.4" | 0 | 10 | 0 | 62° – 70° |
| October | 65° | 43° | 3.0" | 0.4" | 11 | 0 | 50° – 60° |
| November | 53° | 34° | 2.8" | 2.4" | 12 | 1 | 37° – 49° |
| December | 42° | 27° | 3.0" | 7.7" | 15 | 8 | 24° – 45° |
| Year | 63° | 42° | 40.3" | 44.1" | 154 | 40 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Upper St. Clair
Upper St. Clair gets 40 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 154 days a year. Snow covers the ground about 40 days of the year.
About 193 frost-free days a year
In half of years the last 32° night comes by April 18 and the first one by October 28. That leaves about 193 frost-free days for gardens, longer than 67% of U.S. towns.
Heating and cooling a home in Upper St. Clair
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Upper St. Clair, 87% of that work is heating and 13% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Upper St. Clair and its neighbors
Upper St. Clair borders 6 towns with climate data. January nights across them vary by 0.7°. South Fayette has the coldest January nights (21°) and Bridgeville the hottest July afternoons (84°). Upper St. Clair’s January low is 22° and its July high 84°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Upper St. Clair compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Upper St. Clair averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.4°). The shift is smaller than in 51% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Upper St. Clair’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 19° to 41°. June is the most reliable, staying within 7°.
Common questions about Upper St. Clair’s climate
What is the coldest month in Upper St. Clair?
January, with a typical high of 38° and a low of 22°.
What is the hottest month in Upper St. Clair?
July, with a typical high of 84° and a low of 63°. About 8 days a year reach 90°.
How much snow does Upper St. Clair get?
About 44 inches in a normal winter, most of it in January.
When is the first frost in Upper St. Clair?
In half of years the first 32° night comes by October 28, and the last spring frost by April 18.
What is the rainiest month in Upper St. Clair?
June, with 4.2 inches of rain and melted snow. The year totals 40 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Upper St. Clair itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Pittsburgh Intl Airport, PA (12 mi, snow) and Pittsburgh Allegheny Co Airport, PA (9 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.