December weather forecast and climate
Roberts, MT

The first month of the winter, December, is still a freezing cold month in Roberts, Montana, with average temperature fluctuating between 17.4°F (-8.1°C) and 30.7°F (-0.7°C).

Temperature

The coldest month is December, with an average high-temperature of 30.7°F (-0.7°C) and an average low-temperature of 17.4°F (-8.1°C).

Humidity

In Roberts, the average relative humidity is 74%.

Rainfall

In Roberts, in December, during 6.2 rainfall days, 0.63" (16mm) of precipitation is typically accumulated. Throughout the year, there are 108.1 rainfall days, and 12.83" (326mm) of precipitation is accumulated.

Snowfall

Months with snowfall are January through June, September through December. In Roberts, in December, during 9.6 snowfall days, 4.72" (120mm) of snow is typically accumulated. In Roberts, Montana, during the entire year, snow falls for 61.5 days, and aggregates up to 41.77" (1061mm) of snow.

Daylight

December has the shortest days of the year, with an average of 8.8h of daylight.

Sunshine

In December, the average sunshine is 6.4h.

UV index

January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Roberts. A UV Index reading of 2, and below, represents a minimal health hazard from unprotected exposure to the Sun's UV rays for the average person.
Note: The average daily UV index of 2 transform into the following instructions:
Most people can stay in the Sun for up to 1 hour without burning, apart from children that always must be protected from sun exposure. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the coldest month in Roberts?

The coldest month in Roberts is December, with an average high-temperature of 30.7°F (-0.7°C) and an average low-temperature of 17.4°F (-8.1°C).

What is the temperature in December in Roberts?

In Roberts, Montana, in December, the average high-temperature is 30.7°F (-0.7°C), and the average low-temperature is 17.4°F (-8.1°C).

What is the average humidity in December in Roberts?

The average relative humidity in December in Roberts is 74%.

How much does it rain in Roberts in December?

In Roberts, Montana, in December, it is raining for 6.2 days, with typically 0.63" (16mm) of accumulated precipitation.

How much does it snow in Roberts in December?

In December, in Roberts, it is snowing for 9.6 days. Throughout December, 4.72" (120mm) of snow is accumulated.

What is the month with the shortest days in Roberts?

With an average of 8.8h of daylight, December has the shortest days of the year.

How many hours of daylight does Roberts have in December?

The average length of the day in December in Roberts, Montana, is 8.8h.

How many hours of sunshine does Roberts have in December?

The average sunshine in December in Roberts, Montana, is 6.4h.

When is the lowest UV index in Roberts?

January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index.

What is the UV index intensity in December in Roberts?

In December, the average daily maximum UV index in Roberts is 2. A UV Index estimate of 2, and below, represents a minimal hazard to health from unprotected exposure to the UV radiation.
Average temperature in December - Roberts, MT
  • Average high temperature in December: -0.7°C

The warmest month (with the highest average high temperature) is July (28.3°C).
The month with the lowest average high temperature is December (-0.7°C).

  • Average low temperature in December: -8.1°C

Months with the highest average low temperature are July and August (14°C).
The coldest month (with the lowest average low temperature) is February (-8.5°C).

Average pressure in December - Roberts, MT
  • Average pressure in December: 1021mbar

The month with the highest atmospheric pressure is January (1021.1mbar).
The month with the lowest atmospheric pressure is June (1011.9mbar).

Average wind speed in December - Roberts, MT
  • Average wind speed in December: 13.6km/h

The windiest month (with the highest average wind speed) is January (14km/h).
The calmest month (with the lowest average wind speed) is August (9.6km/h).

Average humidity in December - Roberts, MT
  • Average humidity in December: 74%

The month with the highest relative humidity is January (76%).
The month with the lowest relative humidity is August (41%).

Average rainfall in December - Roberts, MT
  • Average rainfall in December: 16mm

The wettest month (with the highest rainfall) is May (53mm).
The driest month (with the least rainfall) is January (13mm).

Average rainfall days in December - Roberts, MT
  • Average rainfall days in December: 6.2 days

The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is February (4 days).

Average snowfall in December - Roberts, MT
  • Average snowfall in December: 120mm

The month with the highest snowfall is February (173mm).
Months with the least snowfall are July and August (0mm).

Average snowfall days in December - Roberts, MT
  • Average snowfall days in December: 9.6 days

The month with the highest number of snowfall days is February (10.8 days).
Months with the least snowfall days are July and August (0 days).

Average daylight in December / Average sunshine in December - Roberts, MT
  • Average daylight in December: 8.8h

The month with the longest days is June (Average daylight: 15.6h).
The month with the shortest days is December (Average daylight: 8.8h).

  • Average sunshine in December: 6.4h

The month with the most sunshine is July (Average sunshine: 11.9h).
The month with the least sunshine is February (Average sunshine: 6.2h).

Average sunshine days in December - Roberts, MT
  • Average sunshine days in December: 19.7 days

The month with the most sunshine days is December (19.7 days).
The month with the least sunshine days is May (10.5 days).

Average UV index in December - Roberts, MT
  • Average UV index in December: 2

The month with the highest UV index is July (UV index 6).
Months with the lowest UV index are January, February, March, November and December (UV index 2).

Average cloud cover in December - Roberts, MT
  • Average cloud cover in December: 33

The month with the most cloud cover is February (Cloud cover 38).
Months with the least cloud cover are July and August (Cloud cover 15).

Average visibility in December - Roberts, MT
  • Average visibility in December: 9km

Months with the highest visibility are June, July, August, September and October (10km).
Months with the lowest visibility are January, February, March, April, May, November and December (9km).