December weather forecast
Saint Mary, MO

Share

Weather in December

The first month of the winter, December, is still a chilly month in Saint Mary, Missouri, with an average temperature varying between 43.7°F (6.5°C) and 31.1°F (-0.5°C).

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.
[Resources]

Frequently asked questions

How cold is it in Saint Mary in December?

The average high-temperature and low-temperature during December are 43.7°F (6.5°C) and 31.1°F (-0.5°C) respectively. In August, the average heat index (a.k.a. 'apparent temperature', 'feels like'), which represents the influence of relative humidity on air temperature, is calculated to be 98.6°F (37°C).

What is the average humidity in December in Saint Mary?

The average relative humidity in December in Saint Mary, Missouri, is 77%.

How many days does it rain in December in Saint Mary?

In Saint Mary, Missouri, in December, it is raining for 9.1 days, with typically 2.4" (61mm) of accumulated precipitation.

How many days does it snow in December in Saint Mary?

In December, in Saint Mary, Missouri, it is snowing for 3 days. Throughout December, 1.18" (30mm) of snow is accumulated.

What is the month with the shortest days in Saint Mary?

December has the shortest days of the year in Saint Mary, with an average of 9h and 36min of daylight.

How many hours of daylight does Saint Mary have in December?

The average day length in December is 9h and 35min.

When is the sunrise / sunset in December in Saint Mary?

On the first day of December in Saint Mary, sunrise is at 6:57 am and sunset at 4:40 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 4:50 pm CST.

How many hours of sunshine does Saint Mary have in December?

In December, the average sunshine duration is 5h.

What is the month with the lowest UV index in Saint Mary?

The months with the lowest UV index in Saint Mary are January, February and December, with an average maximum UV index of 2.

What is the UV index reading in December in Saint Mary?

In Saint Mary, the average daily maximum UV index in December is 2. A UV Index reading of 2, and below, represents a low health threat from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Saint Mary, MO

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).

[Resources]

Average pressure in December
Saint Mary, MO

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).

[Resources]

Average wind speed in December
Saint Mary, MO

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).

[Resources]

Average humidity in December
Saint Mary, MO

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%).

[Resources]

Average rainfall in December
Saint Mary, MO

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").

[Resources]

Average rainfall days in December
Saint Mary, MO

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).

[Resources]

Average snowfall in December
Saint Mary, MO

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").

[Resources]

Average snowfall days in December
Saint Mary, MO

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).

[Resources]

Average daylight in December /
Average sunshine in December
Saint Mary, MO

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).

[Resources]

Average sunshine days in December
Saint Mary, MO

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).

[Resources]

Average UV index in December
Saint Mary, MO

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).

[Resources]

Average cloud cover in December
Saint Mary, MO

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).

[Resources]

Average visibility in December
Saint Mary, MO

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).

[Resources]

Saint Mary, Missouri, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location