Jackson
Wyoming, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Jackson, WY

A calm and clear river and vast green fields approaching the iconic white mountains within the Grand Teton National Park in Jackson, Wyoming
A calm and clear river and vast green fields approaching the iconic white mountains within the Grand Teton National Park in Jackson, Wyoming
The first month of the winter, December, is still a freezing cold month in Jackson, Wyoming, with temperature in the range of an average high of 21.9°F (-5.6°C) and an average low of 32°F (0°C).

Temperature

With an average high-temperature of 21.9°F (-5.6°C) and an average low-temperature of 32°F (0°C), December is the coldest month.

Humidity

In Jackson, the average relative humidity in December is 92%.

Rainfall

In Jackson, in December, during 4.2 rainfall days, 2.91" (74mm) of precipitation is typically accumulated. In Jackson, during the entire year, the rain falls for 103 days and collects up to 29.84" (758mm) of precipitation.

Snowfall

Months with snowfall in Jackson are January through December. In Jackson, during December, snow falls for 23.7 days and regularly aggregates up to 24.72" (628mm) of snow. Throughout the year, there are 173.6 snowfall days, and 181.26" (4604mm) of snow is accumulated.

Daylight

December has the shortest days of the year, with an average of 9h of daylight.

Sunshine

The average sunshine in December is 3.6h.

UV index

January through April, October through December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a low health risk from the exposure to the Sun's UV radiation for ordinary individuals.
Note: In December, the average maximum UV index of 1 translate into the following recommendations:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the coldest month in Jackson?

December is the coldest month in Jackson, with an average high-temperature of 21.9°F (-5.6°C) and an average low-temperature of 32°F (0°C).

What is the temperature in December in Jackson?

In December, in Jackson, Wyoming, the average high-temperature is 21.9°F (-5.6°C), and the average low-temperature is 32°F (0°C).

What is the average humidity in December in Jackson?

In Jackson, Wyoming, the average relative humidity in December is 92%.

How much does it rain in Jackson in December?

In December, in Jackson, Wyoming, the rain falls for 4.2 days. Throughout December, 2.91" (74mm) of precipitation is accumulated.

How many days does it snow in December in Jackson?

In Jackson, in December, snow falls for 23.7 days, with typically accumulated 24.72" (628mm) of snow.

What is the month with the shortest days in Jackson?

With an average of 9h of daylight, December has the shortest days of the year in Jackson.

How many hours of daylight does Jackson have in December?

In December, the average length of the day in Jackson is 9h.

How many hours of sunshine does Jackson have in December?

In December, the average sunshine in Jackson, Wyoming, is 3.6h.

What are the months with the lowest UV index in Jackson?

January through April, October through December, with an average maximum UV index of 1, are months with the lowest UV index in Jackson, Wyoming.

What is the UV index reading in December in Jackson?

In Jackson, Wyoming, the average daily maximum UV index in December is 1. A UV Index value of 2, and less, symbolizes a low health risk from unprotected exposure to the UV radiation.
Average temperature in December - Jackson, WY
  • Average high temperature in December: 21.9°F

The warmest month (with the highest average high temperature) is July (73.4°F).
The month with the lowest average high temperature is December (21.9°F).

  • Average low temperature in December: 0°F

Months with the highest average low temperature are January, February, March, April, May, June, July, August, September, October, November and December (0°F).
Coldest months (with the lowest average low temperature) are January, February, March, April, May, June, July, August, September, October, November and December (0°F).

Average humidity in December - Jackson, WY
  • Average humidity in December: 92%

The month with the highest relative humidity is February (94%).
The month with the lowest relative humidity is August (50%).

Average rainfall in December - Jackson, WY
  • Average rainfall in December: 2.91"

The wettest month (with the highest rainfall) is February (3.54").
The driest month (with the lowest rainfall) is August (1.34").

Average rainfall days in December - Jackson, WY
  • Average rainfall days in December: 4.2 days

The month with the highest number of rainy days is May (15.4 days).
The month with the lowest number of rainy days is January (2.9 days).

Average snowfall in December - Jackson, WY
  • Average snowfall in December: 24.72"

The month with the highest snowfall is February (29.33").
The month with the lowest snowfall is August (0.12").

Average snowfall days in December - Jackson, WY
  • Average snowfall days in December: 23.7 days

The month with the highest number of snowfall days is March (24.8 days).
The month with the lowest number of snowfall days is July (0.4 days).

Average daylight in December / Average sunshine in December - Jackson, WY
  • Average daylight in December: 9h

The month with the longest days is June (Average daylight: 15.4h).
The month with shortest days is December (Average daylight: 9h).

  • Average sunshine in December: 3.6h

The month with most sunshine is July (Average sunshine: 11.6h).
The month with least sunshine is February (Average sunshine: 3.4h).

Average UV index in December - Jackson, WY
  • Average UV index in December: 1

The month with the highest UV index is July (UV index 5).
Months with the lowest UV index are January, February, March, April, October, November and December (UV index 1).