Keystone, CO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Keystone, a community in Summit County, Colorado.
Overnight
45°F
Patchy Smoke
Patchy smoke. Mostly clear, with a low around 45. South southeast wind around 9 mph.
7-day forecast for Keystone
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 45°F | Patchy Smoke | 9 mph SSE | 0% |
| Tuesday | 66°F | Patchy Smoke | 6 to 16 mph SW | 20% |
| Tuesday Night | 45°F | Patchy Smoke then Mostly Clear | 7 to 13 mph SSW | 9% |
| Wednesday | 65°F | Sunny | 7 to 16 mph W | 0% |
| Wednesday Night | 44°F | Mostly Clear | 5 to 15 mph WSW | 0% |
| Thursday | 67°F | Sunny | 6 to 14 mph WNW | 0% |
| Thursday Night | 46°F | Clear | 5 to 14 mph W | 0% |
| Friday | 69°F | Sunny | 5 to 13 mph W | 0% |
| Friday Night | 47°F | Mostly Clear | 5 to 9 mph SE | 0% |
| Saturday | 69°F | Sunny | 5 to 10 mph W | 2% |
| Saturday Night | 49°F | Partly Cloudy | 5 to 9 mph SSE | 1% |
| Sunday | 69°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 5 to 9 mph W | 15% |
| Sunday Night | 50°F | Partly Cloudy | 5 to 8 mph WSW | 7% |
| Monday | 68°F | Mostly Sunny then Chance Showers And Thunderstorms | 3 to 8 mph W | 51% |
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 Aug 4, 2026.