St. Louis, MO weather in December
St. Louis is chilly in December, with some rain and some snow: highs average 45°F and nights drop to about 29°F. Expect about 9 wet days. Snowfall averages about 3.2 in. This is the depth of winter in St. Louis.
- Normal high
- 45°F
- Normal low
- 29°F
- Wet days
- 9
- 2.5 in total
- Snowfall
- 3.2 in
- snow on the ground 4 days
How December changes from start to finish
| December 1 | December 31 | |
|---|---|---|
| Normal high | 49°F | 41°F |
| Normal low | 32°F | 25°F |
| Chance of a wet day | 30% | 30% |
| Sunrise / sunset | 6:59 am / 4:39 pm | 7:18 am / 4:49 pm |
| Daylight | 9.7 h | 9.5 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Central Time).
A typical December day
- 6 am33°Fdew point 26°F
- 9 am35°Fdew point 27°F
- Noon40°Fdew point 28°F
- 3 pm42°Fdew point 28°F
- 6 pm39°Fdew point 28°F
- 9 pm37°Fdew point 28°F
NOAA hourly normals (local standard time) from St Louis Lambert Intl Airport (13 mi away); average wind 9 mph; clear or few clouds in 27% of daytime hours, mostly cloudy or overcast in 62%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F2 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 snow9 of 31
- Notable rainat least 0.10 in5 of 31
- Freezing nightslow 32°F or below20 of 31
- Snow on the groundsnow depth 1 in or more4 of 31
Average days per December, counted from daily records for each year 1991-2020.
Rain and snow in December
Normal precipitation is 2.5 in; a dry December brings about 1.5 in and a wet one about 2.8 in (25th and 75th percentiles). About 1 day brings half an inch or more. Normal snowfall is 3.2 in, with about 1 day of an inch or more.
How December varies from year to year
- Warmest December, 1991-20202015: average high 53°F
- Coolest December2000: average high 29°F
- Wettest December2015: 11.7 in
- Driest December1998: 0.8 in
- Highest reading75°F (December 2, 2012)
- Lowest reading2°F (December 31, 2017)
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 | 56°F | 45°F | 40°F |
| Normal low | 37°F | 29°F | 24°F |
| Wet days | 9 | 9 | 9 |
| Comfortable days | 7 | 2 | 1 |
| Daylight | 10.1 h | 9.5 h | 9.8 h |
Highs change by -11°F from November and -5°F into January.
Nearby alternatives in December
- Warmer: Clarksville, TN212 mi · high 50°F · 12 wet days
- Drier: Lee's Summit, MO226 mi · high 42°F · 5 wet days
- Cooler: Peoria, IL146 mi · high 39°F · 10 wet days
How St. Louis ranks in December
- Normal high241st warmest of 378 cities; 3rd of 7 in Missouri
- Wet days164th driest of 378
- Comfortable days186th most of 340
What to pack for St. Louis in December
- A warm jacket – lows near 29°F, highs near 45°F
- A rain jacket or umbrella – rain or snow on about 9 days
- Waterproof boots – about 3.2 in of snow in a typical year
- A hat and gloves – about 20 freezing nights
Heating and cooling
December has 884 heating degree days and 0 cooling degree days (base 65°F), 14% of the year's total heating and cooling demand.
Questions
How cold is St. Louis in December?
The normal high is 45°F and the normal low is 29°F. From 1991 to 2020 the coldest December reading was 2°F (most recently on December 31, 2017).
Does it rain a lot in St. Louis in December?
About 9 days in December have at least 0.01 in of precipitation, and the normal total is 2.5 in. The wettest December in 1991-2020 was in 2015 (11.7 in); the driest was in 1998 (0.8 in).
Does it snow in St. Louis in December?
Yes. Normal snowfall in December is 3.2 in, and snow covers the ground on about 4 days.
Is December a good time to visit St. Louis?
December ranks 11th of 12 months on our comfort score for St. Louis (36 out of 100). It has about 2 comfortable days. The best months are April and May.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, humidity and wind by hour and cloud cover: St Louis Lambert Intl Airport (USW00013994), 13 mi NW of the city center, 531 ft (67 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Frost dates: Cahokia St Louis Airport (USW00003960), 4.4 mi SSE of the city center, 413 ft (51 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Lambert-St Louis International Airport (724340-13994), 13 mi NW of the city center, 531 ft (67 ft higher than the city). Hourly observations, 1991-2020.