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Upper St Clair, PA Weather Forecast
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Upper St Clair Weather Forecast
| TODAY | TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | LABOR DAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT |
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| Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Mostly Sunny | Clear | Mostly Sunny | Clear | Partly Cloudy | Mostly Cloudy | Partly Sunny | Chance of Showers |
| Hi: 85°FHi: 29°C | Lo: 69°FLo: 21°C | Hi: 80°FHi: 27°C | Lo: 59°FLo: 15°C | Hi: 79°FHi: 26°C | Lo: 59°FLo: 15°C | Hi: 80°FHi: 27°C | Lo: 59°FLo: 15°C | Hi: 81°FHi: 27°C | Lo: 65°FLo: 18°C | Hi: 85°FHi: 29°C | Lo: 69°FLo: 21°C |
| POP: 70% | POP: 70% | POP: 50% | POP: 50% | POP: 50% |
POP = Probability of Precipitation.
Weather Outlook Updated: 502 AM EDT Fri Sep 04 2026 
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Meteorlogic Glosserator
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Issued: 133 AM EDT Fri Sep 4 2026
Key Messages
1) Rounds of showers and storms continue through Saturday with associated severe weather threats. A cold front brings dry weather back to the area Sunday into early next week.
Discussion
... KEY MESSAGE 1... The strong ridging that has sat entrenched across the Southeast this week weakens and begins shifting back west over the Plains in response to low pressure deepening off the New England and eastern Canada Atlantic coast. This doesn`t change the pattern over the local area much as w...