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Harrisburg Weather Forecast
| THIS AFTERNOON | TONIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | MONDAY | MONDAY NIGHT | TUESDAY | WEDNESDAY |
 |  | | | |  |  | |  | | |
| Sunny | Mostly Clear | Sunny | Mostly Clear | Sunny | Partly Cloudy | Partly Cloudy | Mostly Sunny | Chance of Showers | Partly Cloudy | Partly Cloudy |
| Hi: 99°FHi: 37°C | Lo: 75°FLo: 24°C | Hi: 99°FHi: 37°C | Lo: 71°FLo: 22°C | Hi: 99°FHi: 37°C | Hi: 99°FHi: 37°C Lo: 71°FLo: 22°C | Hi: 99°FHi: 37°C Lo: 71°FLo: 22°C | Hi: 91°FHi: 33°C | Lo: 65°FLo: 18°C | Hi: 81°FHi: 27°C Lo: 59°FLo: 15°C | Hi: 81°FHi: 27°C Lo: 59°FLo: 15°C |
| POP: 30% |
POP = Probability of Precipitation.
Weather Outlook Updated: 128 PM CDT Thu Sep 17 2026 
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Issued: 1233 PM CDT Thu Sep 17 2026
Key Messages
- A Heat Advisory remains in effect through Sunday evening for daily heat index values between 103-109 degrees. High temperatures during this period will range from the mid 90s to near 100 degrees.
- There is a 20% chance of an isolated shower or thunderstorm this afternoon and Friday afternoon and evening, mainly north along I-64.
- More scattered rain chances across the entire region arrives on Monday, with a 30-40% chance of showers and thunderstorms peaking Monday afternoon into Monday...