Casper, WY weather in December
In December, Casper sees highs around 35°F and lows around 15°F: cold and snowy. Rain or snow falls on about 7 days. Snowfall averages about 11.0 in. It is one of the coldest months in Casper. Dress for deep cold.
- Normal high
- 35°F
- Normal low
- 15°F
- Wet days
- 7
- 0.6 in total
- Snowfall
- 11.0 in
- snow on the ground 16 days
How December changes from start to finish
| December 1 | December 31 | |
|---|---|---|
| Normal high | 38°F | 34°F |
| Normal low | 17°F | 14°F |
| Chance of a wet day | 22% | 21% |
| Sunrise / sunset | 7:16 am / 4:32 pm | 7:36 am / 4:40 pm |
| Daylight | 9.3 h | 9.1 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
A typical December day
- 6 am23°Fdew point 13°F
- 9 am25°Fdew point 14°F
- Noon32°Fdew point 16°F
- 3 pm33°Fdew point 16°F
- 6 pm26°Fdew point 15°F
- 9 pm24°Fdew point 14°F
NOAA hourly normals (local standard time) from Casper Natrona Co Airport (8 mi away); average wind 15 mph; clear or few clouds in 71% of daytime hours, mostly cloudy or overcast in 25%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F0 of 31
- Hot dayshigh 90°F or more0 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow7 of 31
- Notable rainat least 0.10 in2 of 31
- Freezing nightslow 32°F or below29 of 31
- Snow on the groundsnow depth 1 in or more16 of 31
Average days per December, counted from daily records for each year 1991-2020.
Rain and snow in December
Normal precipitation is 0.6 in; a dry December brings about 0.3 in and a wet one about 0.8 in (25th and 75th percentiles). Days with half an inch or more are rare. Normal snowfall is 11.0 in, with about 4 days of an inch or more.
How December varies from year to year
- Warmest December, 1991-20201994: average high 41°F
- Coolest December2009: average high 26°F
- Wettest December2017: 1.4 in
- Driest December2004: 0.07 in
- Highest reading63°F (December 1, 1995)
- Lowest reading-33°F (December 8, 2016)
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 | 46°F | 35°F | 35°F |
| Normal low | 22°F | 15°F | 15°F |
| Wet days | 6 | 7 | 6 |
| Comfortable days | 2 | 0 | 0 |
| Daylight | 9.8 h | 9.1 h | 9.4 h |
Highs change by -11°F from November and 0°F into January.
Nearby alternatives in December
- Warmer: Fort Collins, CO170 mi · high 44°F · 4 wet days
- Drier: Greeley, CO188 mi · high 43°F · 4 wet days
- Cooler: Vail, CO223 mi · high 28°F · 11 wet days
How Casper ranks in December
- Normal high340th warmest of 378 cities; 3rd of 4 in Wyoming
- Wet days119th driest of 378
- Comfortable days338th most of 340
What to pack for Casper in December
- A warm jacket – lows near 15°F, highs near 35°F
- Waterproof boots – snow on the ground on about 16 days
- A hat and gloves – about 29 freezing nights
Heating and cooling
December has 1248 heating degree days and 0 cooling degree days (base 65°F), 16% of the year's total heating and cooling demand.
Questions
How cold is Casper in December?
The normal high is 35°F and the normal low is 15°F. From 1991 to 2020 the coldest December reading was -33°F (December 8, 2016).
Does it rain a lot in Casper in December?
About 7 days in December have at least 0.01 in of precipitation, and the normal total is 0.6 in. The wettest December in 1991-2020 was in 2017 (1.4 in); the driest was in 2004 (0.07 in).
Does it snow in Casper in December?
Yes. Normal snowfall in December is 11.0 in, and snow covers the ground on about 16 days.
Is December a good time to visit Casper?
December ranks 12th of 12 months on our comfort score for Casper (30 out of 100). It has almost no comfortable days. The best month is May.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates, humidity and wind by hour and cloud cover: Casper Natrona Co Airport (USW00024089), 7.9 mi WNW of the city center, 5,338 ft (233 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Natrona County International Airport (725690-24089), 8.4 mi WNW of the city center, 5,319 ft (214 ft higher than the city). Hourly observations, 1991-2020.