Big Sky, MT weather in December
Expect very cold weather with frequent rain in Big Sky in December, with highs near 28°F and lows near 9°F. Rain falls on about 14 days. It is one of the coldest months in Big Sky. Dress for deep cold.
- Normal high
- 28°F
- Normal low
- 9°F
- Wet days
- 14
- 1.7 in total
- Daylight
- 8.8 h
How December changes from start to finish
| December 1 | December 31 | |
|---|---|---|
| Normal high | 30°F | 28°F |
| Normal low | 11°F | 8°F |
| Chance of a wet day | 42% | 46% |
| Sunrise / sunset | 7:44 am / 4:44 pm | 8:04 am / 4:52 pm |
| Daylight | 9.0 h | 8.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
What kind of days to expect
- Comfortable dayshigh 65-80°F (temperature only: no humidity station nearby)0 of 31
- Hot dayshigh 90°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow14 of 31
- Notable rainat least 0.10 in6 of 31
- Freezing nightslow 32°F or below31 of 31
Average days per December, counted from daily records for each year 1991-2020.
Rain in December
Normal precipitation is 1.7 in; a dry December brings about 1.0 in and a wet one about 2.5 in (25th and 75th percentiles). About 1 day brings half an inch or more.
How December varies from year to year
- Warmest December, 1991-20201991: average high 33°F
- Coolest December2009: average high 22°F
- Wettest December1992: 3.4 in
- Driest December2002: 0.5 in
- Highest reading53°F (December 12, 2014)
- Lowest reading-32°F (December 21, 1998)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
December compared with November and January
| November | December | January | |
|---|---|---|---|
| Normal high | 37°F | 28°F | 30°F |
| Normal low | 16°F | 9°F | 9°F |
| Wet days | 11 | 14 | 13 |
| Comfortable days | 0 | 0 | 0 |
| Daylight | 9.5 h | 8.8 h | 9.2 h |
Highs change by -9°F from November and +2°F into January.
Nearby alternatives in December
- Warmer: Billings, MT143 mi · high 37°F · 6 wet days
- Drier: Billings, MT143 mi · high 37°F · 6 wet days
How Big Sky ranks in December
- Normal high370th warmest of 378 cities; 5th of 6 in Montana
- Wet days336th driest of 378
What to pack for Big Sky in December
- A warm jacket – lows near 9°F, highs near 28°F
- A rain jacket or umbrella – rain on about 14 days
- A hat and gloves – about 31 freezing nights
Heating and cooling
December has 1457 heating degree days and 0 cooling degree days (base 65°F), 15% of the year's total heating and cooling demand.
Questions
How cold is Big Sky in December?
The normal high is 28°F and the normal low is 9°F. From 1991 to 2020 the coldest December reading was -32°F (December 21, 1998).
Does it rain a lot in Big Sky in December?
About 14 days in December have at least 0.01 in of precipitation, and the normal total is 1.7 in. The wettest December in 1991-2020 was in 1992 (3.4 in); the driest was in 2002 (0.5 in).
Is December a good time to visit Big Sky?
December ranks 12th of 12 months on our comfort score for Big Sky (22 out of 100). It has almost no comfortable days (judged by temperature only). The best months are June, July and September.
Where the numbers come from
- Temperature and rain: Big Sky 2WNW (USC00240775), 2.1 mi ESE of the city center, 6,590 ft (630 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Not available for this location: snowfall, snow depth, frost dates, humidity and wind by hour, cloud cover and daily humidity and wind (no station close enough or similar enough in elevation).