Keystone, CO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Keystone, a community in Summit County, Colorado.
This Afternoon
52°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy. High near 52, with temperatures falling to around 50 in the afternoon. West southwest wind around 7 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for Keystone
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 52°F | Showers And Thunderstorms Likely | 7 mph WSW | 74% |
| Tonight | 40°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 7 mph SW | 35% |
| Saturday | 50°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 5 to 10 mph WSW | 46% |
| Saturday Night | 34°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 3 to 10 mph SW | 17% |
| Sunday | 48°F | Mostly Sunny | 5 to 17 mph W | 10% |
| Sunday Night | 33°F | Mostly Clear | 3 to 14 mph WNW | 0% |
| Monday | 53°F | Sunny | 3 to 13 mph W | 0% |
| Monday Night | 36°F | Mostly Clear | 7 mph ESE | 1% |
| Tuesday | 53°F | Partly Sunny then Chance Showers And Thunderstorms | 3 to 8 mph SW | 54% |
| Tuesday Night | 37°F | Chance Showers And Thunderstorms then Mostly Cloudy | 3 to 9 mph SSE | 35% |
| Wednesday | 52°F | Partly Sunny then Chance Showers And Thunderstorms | 3 to 9 mph WSW | 42% |
| Wednesday Night | 37°F | Chance Rain Showers then Mostly Cloudy | 2 to 7 mph WNW | 25% |
| Thursday | 53°F | Partly Sunny then Chance Showers And Thunderstorms | 2 to 8 mph SW | 35% |
| Thursday Night | 38°F | Chance Rain Showers | 7 mph S | 33% |
Forecast source: National Weather Service (api.weather.gov) for Keystone (39.574, -105.935). Updated through the day.
Growing snapshot for Keystone
Growing season
41 days
Hardiness zone
5a
More local growing data for Keystone: nearby ZIP 80435 weather · frost dates · planting calendar · Colorado frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Dillon 1 E, Co (6.5 mi from Keystone). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.