Castle Valley, UT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Castle Valley, a town in Grand County, Utah.
Tonight
56°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before midnight, then a chance of showers and thunderstorms between midnight and 5am, then a slight chance of showers and thunderstorms. Mostly cloudy, with a low around 56. Southeast wind 5 to 10 mph. Chance of precipitation is 50%.
7-day forecast for Castle Valley
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 56°F | Chance Showers And Thunderstorms | 5 to 10 mph SE | 53% |
| Saturday | 80°F | Slight Chance Showers And Thunderstorms | 5 to 10 mph NW | 18% |
| Saturday Night | 55°F | Mostly Clear | 0 to 10 mph S | 7% |
| Sunday | 78°F | Sunny | 0 to 5 mph N | 0% |
| Sunday Night | 55°F | Mostly Clear | 0 to 5 mph S | 0% |
| Monday | 81°F | Mostly Sunny | 0 to 5 mph N | 0% |
| Monday Night | 56°F | Partly Cloudy then Slight Chance Rain Showers | 0 to 5 mph E | 15% |
| Tuesday | 79°F | Chance Showers And Thunderstorms | 0 to 5 mph S | 44% |
| Tuesday Night | 55°F | Showers And Thunderstorms Likely | 0 to 5 mph SE | 56% |
| Wednesday | 78°F | Chance Rain Showers then Slight Chance Showers And Thunderstorms | 0 to 5 mph NNE | 30% |
| Wednesday Night | 55°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph E | 12% |
| Thursday | 80°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 0 to 5 mph NNE | 24% |
| Thursday Night | 57°F | Chance Showers And Thunderstorms | 0 to 5 mph E | 33% |
| Friday | 79°F | Chance Rain Showers | 0 to 5 mph SSW | 39% |
Forecast source: National Weather Service (api.weather.gov) for Castle Valley (38.632, -109.396). Updated through the day.
Growing snapshot for Castle Valley
Last spring frost
Apr 19
First fall frost
Oct 21
Growing season
184 days
Hardiness zone
7a
More local growing data for Castle Valley: nearby ZIP 84532 weather · frost dates · planting calendar · Utah frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Castle Valley 1Se, Ut (7.3 mi from Castle Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.