Williamstown, PA Weather Forecast
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| TODAY | TONIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT |
| Sunny | Clear | Sunny | Clear | Sunny | Mostly Clear | Sunny | Mostly Clear | Sunny | Mostly Clear | Sunny | Partly Cloudy |
| Hi: 69°FHi: 21°C | Lo: 41°FLo: 5°C | Hi: 61°FHi: 16°C | Lo: 41°FLo: 5°C | Hi: 70°FHi: 21°C | Lo: 51°FLo: 11°C | Hi: 71°FHi: 22°C | Lo: 49°FLo: 9°C | Hi: 71°FHi: 22°C | Lo: 49°FLo: 9°C | Hi: 69°FHi: 21°C | Lo: 49°FLo: 9°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 900 AM EDT Mon Oct 05 2026 

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Issued: 709 AM EDT Mon Oct 5 2026
Key Messages
1) Frost/freeze conditions are probable late tonight and early Tuesday morning over the western and central Alleghenies
2) Extended stretch of dry and seasonal Fall weather this week
Discussion
... KEY MESSAGE 1: Frost/freeze conditions are probable late tonight and early Tuesday morning over the western and central Alleghenies
As of 0730Z, a light southwesterly breeze developing just ahead of a SEWD-pushing cold front was helping to erode the northern and western edge of the widespread ...
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