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Castle Rock, CO Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Castle Rock, a town in Douglas County, Colorado.

Overnight
52°F
Partly Cloudy
Partly cloudy, with a low around 52. West southwest wind around 3 mph.

7-day forecast for Castle Rock

WhenTempForecastWindPrecip
Overnight 52°F Partly Cloudy 3 mph WSW 1%
Saturday 75°F Mostly Sunny then Chance Showers And Thunderstorms 2 to 8 mph SSW 53%
Saturday Night 49°F Chance Showers And Thunderstorms then Partly Cloudy 2 to 6 mph SSE 45%
Sunday 70°F Mostly Sunny then Chance Showers And Thunderstorms 2 to 9 mph NW 42%
Sunday Night 48°F Chance Showers And Thunderstorms 1 to 7 mph WSW 38%
Monday 71°F Mostly Sunny 1 to 9 mph SE 6%
Monday Night 50°F Chance Showers And Thunderstorms 8 to 12 mph SSE 30%
Tuesday 74°F Mostly Sunny then Slight Chance Showers And Thunderstorms 3 to 12 mph SSE 19%
Tuesday Night 51°F Slight Chance Showers And Thunderstorms then Mostly Cloudy 8 to 12 mph S 19%
Wednesday 75°F Partly Sunny then Slight Chance Showers And Thunderstorms 3 to 7 mph S 16%
Wednesday Night 51°F Slight Chance Showers And Thunderstorms then Mostly Cloudy 2 to 6 mph SSW 19%
Thursday 75°F Mostly Sunny 2 to 7 mph ESE 12%
Thursday Night 53°F Slight Chance Rain Showers then Mostly Cloudy 8 mph SSE 19%
Friday 76°F Mostly Sunny then Slight Chance Showers And Thunderstorms 6 to 10 mph SSE 20%

Forecast source: National Weather Service (api.weather.gov) for Castle Rock (39.376, -104.853). Updated through the day.

Growing snapshot for Castle Rock

Last spring frost
May 9
First fall frost
Oct 2
Growing season
143 days
Hardiness zone
5b

More local growing data for Castle Rock: nearby ZIP 80109 weather · frost dates · planting calendar · Colorado frost dates

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Climate data from the nearest NOAA station, Castle Rock, Co (2.7 mi from Castle Rock). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.