Newcastle, UT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Newcastle, a community in Iron County, Utah.
This Afternoon
52°F
Sunny
Sunny, with a high near 52. South southwest wind around 3 mph.
7-day forecast for Newcastle
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 52°F | Sunny | 3 mph SSW | 0% |
| Tonight | 32°F | Mostly Clear | 3 mph SSE | 10% |
| Wednesday | 52°F | Sunny | 2 to 8 mph N | 10% |
| Wednesday Night | 28°F | Patchy Fog | 1 to 8 mph NE | 0% |
| Thursday | 52°F | Patchy Fog then Mostly Sunny | 3 mph NNE | 0% |
| Thursday Night | 30°F | Mostly Clear | 1 to 6 mph NE | 0% |
| Friday | 53°F | Sunny | 6 to 13 mph NE | 0% |
| Friday Night | 29°F | Mostly Clear | 5 to 10 mph NE | 0% |
| Saturday | 57°F | Sunny | 3 to 7 mph NE | 0% |
| Saturday Night | 31°F | Mostly Clear | 0 to 3 mph NNE | 0% |
| Sunday | 62°F | Sunny | 2 mph NNW | 0% |
| Sunday Night | 34°F | Mostly Clear | 0 mph | 0% |
| Monday | 62°F | Mostly Sunny | 0 to 3 mph WSW | 2% |
| Monday Night | 36°F | Partly Cloudy | 2 mph SSW | 2% |
Forecast source: National Weather Service (api.weather.gov) for Newcastle (37.663, -113.564). Updated through the day.
Growing snapshot for Newcastle
Last spring frost
May 31
First fall frost
Sep 20
Growing season
110 days
Hardiness zone
5b
More local growing data for Newcastle: nearby ZIP 84756 weather · frost dates · planting calendar · Utah frost dates
Nearby towns & communities
Beryl Junction
Brian Head
Cedar City
Cedar Highlands
Enoch
Kanarraville
Modena
Paragonah
Parowan
Summit
Climate data from the nearest NOAA station, Enterprise Beryl Jct, Ut (6.2 mi from Newcastle). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.