Newcastle, UT Weather Forecast
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Newcastle Weather Forecast
| TONIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | TUESDAY | WEDNESDAY |
| Chance of T-Storm | Chance of T-Storm | Mostly Clear | Chance of T-Storm | Chance of T-Storm | Sunny | Clear | Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy | Chance of Showers |
| Lo: 59°FLo: 15°C | Hi: 80°FHi: 27°C | Lo: 55°FLo: 13°C | Hi: 80°FHi: 27°C | Lo: 50°FLo: 10°C | Hi: 79°FHi: 26°C | Lo: 49°FLo: 9°C | Hi: 80°FHi: 27°C | Hi: 80°FHi: 27°C Lo: 50°FLo: 10°C | Hi: 80°FHi: 27°C Lo: 50°FLo: 10°C | Hi: 80°FHi: 27°C Lo: 50°FLo: 10°C | Hi: 80°FHi: 27°C |
| POP: 50% | POP: 30% | POP: 20% | POP: 10% | POP: 30% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1053 PM MDT Wed Sep 16 2026 

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Issued: 1033 PM MDT Wed Sep 16 2026
Key Messages
.KEY MESSAGES, Issued 1253 PM MDT Wed Sep 16 2026...- Flash flooding remains the primary weather risk across southern and eastern Utah through Friday. Multiple rounds of showers and thunderstorms will bring the threat for locally heavy rainfall.
- A Flood Watch for Flash Flooding has been issued from late tonight through Thursday morning for much of southern Utah, while the Watch extends through Thursday evening for much of Carbon and Emery Counties.
- A marginal risk for severe thunderst...
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