St. Clair, PA Weather & Growing Conditions
Today
85°F
Sunny
Sunny, with a high near 85. East wind around 2 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 85°F | Sunny | 2 mph E | 0% |
| Tonight | 65°F | Mostly Cloudy | 2 mph E | 3% |
| Wednesday | 80°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 0 to 3 mph E | 61% |
| Wednesday Night | 70°F | Chance Showers And Thunderstorms then Patchy Fog | 2 mph SE | 54% |
| Thursday | 86°F | Patchy Fog then Showers And Thunderstorms | 0 to 5 mph S | 84% |
| Thursday Night | 71°F | Showers And Thunderstorms | 2 mph SW | 84% |
| Friday | 86°F | Showers And Thunderstorms | 0 to 3 mph W | 75% |
| Friday Night | 68°F | Showers And Thunderstorms then Chance Showers And Thunderstorms | 2 mph W | 75% |
| Saturday | 85°F | Partly Sunny then Showers And Thunderstorms Likely | 0 to 3 mph W | 57% |
| Saturday Night | 68°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 2 mph W | 57% |
| Sunday | 87°F | Mostly Sunny | 0 to 3 mph W | 12% |
| Sunday Night | 69°F | Mostly Clear | 2 mph W | 12% |
| Monday | 88°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 6 mph W | 22% |
| Monday Night | 68°F | Slight Chance Showers And Thunderstorms | 0 to 5 mph W | 22% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Clair, PA
Last spring frost
Apr 30
First fall frost
Oct 22
Growing season
175 days
Hardiness zone
6b
Explore more for St. Clair, PA: full frost dates · planting calendar · Pennsylvania frost dates
Climate data from the nearest NOAA station, Mahanoy City 2 N, Pa (8.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.