Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
The arrival of December corresponds with a reduction in the average high-temperature, down from November's cool 53.8°F (12.1°C) to a frosty 43.7°F (6.5°C). An average low-temperature of 31.1°F (-0.5°C) is anticipated throughout the nights during December.Humidity
The average relative humidity in December is 77%.Rainfall
In Saint Mary, Missouri, in December, during 9.1 rainfall days, 2.4" (61mm) of precipitation is typically accumulated. Throughout the year, there are 156.4 rainfall days, and 34.25" (870mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall in Saint Mary. In Saint Mary, in December, during 3 snowfall days, 1.18" (30mm) of snow is typically accumulated. Throughout the year, there are 16 snowfall days, and 6.89" (175mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 36min of daylight.On the first day of the month, sunrise is at 6:57 am and sunset at 4:40 pm. On the last day of December, sunrise is at 7:15 am and sunset at 4:50 pm CST.
Sunshine
The average sunshine in December in Saint Mary is 5h.UV index
January, February and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high daily UV index of 2 during December translates into the following directions:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Boost your sun resistance with garments that are densely woven yet spacious. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in Saint Mary in December?
What is the average humidity in December in Saint Mary?
How many days does it rain in December in Saint Mary?
How many days does it snow in December in Saint Mary?
What is the month with the shortest days in Saint Mary?
How many hours of daylight does Saint Mary have in December?
When is the sunrise / sunset in December in Saint Mary?
How many hours of sunshine does Saint Mary have in December?
What is the month with the lowest UV index in Saint Mary?
What is the UV index reading in December in Saint Mary?
Average temperature in December
Saint Mary, MO
- Average high temperature in December: 43.7°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in December: 31.1°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in December
Saint Mary, MO
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Saint Mary, MO
- Average wind speed in December: 8.6mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in December
Saint Mary, MO
- Average humidity in December: 77%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Saint Mary, MO
- Average rainfall in December: 2.4"
The wettest month (with the highest rainfall) is April (4.13").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in December
Saint Mary, MO
- Average rainfall days in December: 9.1 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is January (7.9 days).
Average snowfall in December
Saint Mary, MO
- Average snowfall in December: 1.18"
The month with the highest snowfall is February (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Saint Mary, MO
- Average snowfall days in December: 3 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Saint Mary, MO
- Average daylight in December: 9h and 4min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 0min
The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in December
Saint Mary, MO
- Average sunshine days in December: 18.7 days
The month with the most sunshine days is October (18.9 days).
The month with the least sunshine days is July (9.8 days).
Average UV index in December
Saint Mary, MO
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in December
Saint Mary, MO
- Average cloud cover in December: 47
The months with the most cloud cover are January and February (Cloud cover 48).
The month with the least cloud cover is June (Cloud cover 27).
Average visibility in December
Saint Mary, MO
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Saint Mary, Missouri, USA
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