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Keystone in December

Cold and mostly dry, as the days hold steady.

Typical weather, averaged over 30 years

December in Keystone is cold: highs near 39°F, lows near 20°F. Rain or snow falls on about one day a week, and daylight holds at about 8 hours 57 minutes.December in Keystone is cold: highs near 4°C, lows near -7°C. Rain or snow falls on about one day a week, and daylight holds at about 8 hours 57 minutes.

High
39°F4°Caverage
Low
20°F-7°Caverage
Wet days
1a week · 16% of days
Daylight
8h 57mon average

Is December a good time to visit Keystone?

December sits outside Keystone's best months, which run from September. Expect cold days and rain or snow on about one day a week.

How we judge it: every month is scored on how close its typical high comes to the range from 70°F to 80°F, how mild its nights are, and how rarely it rains. The best months are the run of months that scores best.How we judge it: every month is scored on how close its typical high comes to the range from 21°C to 27°C, how mild its nights are, and how rarely it rains. The best months are the run of months that scores best.

How December sits in the year

week by week

Temperature

Highs near 39°F in December, against 38°F to 84°F through the year.Highs near 4°C in December, against 3°C to 29°C through the year.

Chance of a wet day

16% of days in December, against 16% to 57% through the year.

Cloud cover

48% cover in December, against 27% to 54% through the year.

Daylight

8h 57m in December, against 8h 57m to 15h 25m through the year.

Week by week, lightly smoothed, with December shaded. The olive line marks the best months. Hover or tap a week for its figures.

Either side

  1. November49°9°low 29°low -2°1 wet day a weekRain on about one day a week.
  2. December39°4°low 20°low -7°1 wet day a weekRain on about one day a week.
  3. January38°3°low 18°low -8°1 wet day a weekRain on about one day a week.

Where Keystone sits, in December

America/Denver
this place
typical high in December 40°F4°C95°F35°C
Sunrise, mid-December
7:21 AMsets 4:17 PM
Above the sea
1,430 mupland
Latitude
43.9°Nnorthern hemisphere
Nearest of ours
Saratoga386 km south-west

The land around Keystone, shaded by its typical high in December, the planning map's own layer. Hover the map for the figure at that spot; tap it on a phone. Clock times are local, for the 15th.

Elsewhere in United States in December

high · low · wet days
See December on the planning mapThe whole year in Keystone

Typical weather, averaged over 30 years (1995–2024), from the 11 km grid square nearest Keystone. Temperatures are adjusted against 66 weather stations: daytime highs read about 3.1°F cold in the source data and are raised to match.Temperatures are adjusted against 66 weather stations: daytime highs read about 1.7°C cold in the source data and are raised to match. Daylight is calculated from latitude. Charts are lightly smoothed week to week; the figures in the table are not. Source: Copernicus ERA5-Land reanalysis; cloud cover from NASA's MERRA-2 reanalysis, on a coarser grid of about 50 km. Contains modified Copernicus Climate Change Service information 2026; neither the European Commission nor ECMWF is responsible for any use of it. These are averages, not a forecast.

Daylight is calculated from latitude. Charts are lightly smoothed week to week; the figures in the table are not.

Source: Copernicus ERA5-Land reanalysis; cloud cover from NASA's MERRA-2 reanalysis, on a coarser grid of about 50 km. Contains modified Copernicus Climate Change Service information 2026; neither the European Commission nor ECMWF is responsible for any use of it. These are averages, not a forecast.