Rapid City, SD weather in December
Expect cold, mostly dry weather with some snow in Rapid City in December, with highs near 37°F and lows near 14°F. Rain or snow falls on about 5 days. Snowfall averages about 6.6 in. It is one of the coldest months in Rapid City.
- Normal high
- 37°F
- Normal low
- 14°F
- Wet days
- 5
- 0.3 in total
- Snowfall
- 6.6 in
- snow on the ground 10 days
How December changes from start to finish
| December 1 | December 31 | |
|---|---|---|
| Normal high | 41°F | 36°F |
| Normal low | 17°F | 13°F |
| Chance of a wet day | 16% | 17% |
| Sunrise / sunset | 7:07 am / 4:15 pm | 7:27 am / 4:23 pm |
| Daylight | 9.1 h | 8.9 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 am22°Fdew point 14°F
- 9 am26°Fdew point 16°F
- Noon34°Fdew point 18°F
- 3 pm34°Fdew point 18°F
- 6 pm27°Fdew point 17°F
- 9 pm24°Fdew point 16°F
NOAA hourly normals (local standard time) from Ellsworth AFB (8 mi away); average wind 11 mph; clear or few clouds in 49% of daytime hours, mostly cloudy or overcast in 41%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F1 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 snow5 of 31
- Notable rainat least 0.10 in1 of 31
- Freezing nightslow 32°F or below30 of 31
- Snow on the groundsnow depth 1 in or more10 of 31
Average days per December, counted from daily records for each year 1991-2020.
Rain and snow in December
Normal precipitation is 0.3 in; a dry December brings about 0.1 in and a wet one about 0.6 in (25th and 75th percentiles). Days with half an inch or more are rare. Normal snowfall is 6.6 in, with about 2 days of an inch or more.
How December varies from year to year
- Warmest December, 1991-20201999: average high 46°F
- Coolest December2009: average high 25°F
- Wettest December2018: 1.1 in
- Driest December2001: no measurable precipitation
- Highest reading71°F (December 12, 2014)
- Lowest reading-23°F (December 17, 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 | 47°F | 37°F | 36°F |
| Normal low | 22°F | 14°F | 13°F |
| Wet days | 5 | 5 | 6 |
| Comfortable days | 4 | 1 | 1 |
| Daylight | 9.7 h | 8.9 h | 9.3 h |
Highs change by -10°F from November and -1°F into January.
Nearby alternatives in December
- Cooler: Medora, ND196 mi · high 31°F · 6 wet days
How Rapid City ranks in December
- Normal high313th warmest of 378 cities; 1st of 4 in South Dakota
- Wet days48th driest of 378
- Comfortable days230th most of 340
What to pack for Rapid City in December
- A warm jacket – lows near 14°F, highs near 37°F
- Waterproof boots – about 6.6 in of snow in a typical year
- A hat and gloves – about 30 freezing nights
Heating and cooling
December has 1223 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 Rapid City in December?
The normal high is 37°F and the normal low is 14°F. From 1991 to 2020 the coldest December reading was -23°F (most recently on December 17, 2016).
Does it rain a lot in Rapid City in December?
About 5 days in December have at least 0.01 in of precipitation, and the normal total is 0.4 in. The wettest December in 1991-2020 was in 2018 (1.1 in); the driest was in 2001, with no measurable precipitation.
Does it snow in Rapid City in December?
Yes. Normal snowfall in December is 6.6 in, and snow covers the ground on about 10 days.
Is December a good time to visit Rapid City?
December ranks 12th of 12 months on our comfort score for Rapid City (34 out of 100). It has about 1 comfortable day. The best months are May and June.
Where the numbers come from
- Temperature and rain: Rapid City Rgnl Airport (USW00024090), 9.2 mi ESE of the city center, 3,160 ft (83 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snowfall, snow depth and frost dates: Rapid City WFO (USC00396948), 1.1 mi ESE of the city center, 3,379 ft (136 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: Ellsworth AFB (USW00024006), 8.1 mi NE of the city center, 3,215 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Rapid City Regional Airport (726620-24090), 9.1 mi ESE of the city center, 3,162 ft (81 ft lower than the city). Hourly observations, 1991-2020.