Boise
Idaho, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Boise, ID

The golden fall season in Boise, Idaho, with the tall city buildings
The golden fall season in Boise, Idaho, with the tall city buildings
The first month of the winter, December, is also a wintry month in Boise, Idaho, with temperature in the range of an average low of 24.1°F (-4.4°C) and an average high of 37.6°F (3.1°C).

Temperature

With an average high-temperature of 37.6°F (3.1°C) and an average low-temperature of 24.1°F (-4.4°C), December is the coldest month.

Humidity

In Boise, the average relative humidity in December is 74.6%.

Rainfall

The month with the most rainfall in Boise is December when the rain falls for 11.8 days and typically aggregates up to 1.6" (39.4mm) of precipitation.

Snowfall

Months with snowfall in Boise are January through April, October through December. The month with the most snowfall is December when snow falls for 6 days and typically aggregates up to 7" (177.8mm) of snow.

Daylight

The month with the shortest days is December, with an average of 9h of daylight.

Sunshine

December has the least sunshine of the year in Boise, with an average of 3.4h of sunshine.

UV index

January and December, with an average maximum UV index of 1, are months with the lowest UV index in Boise. A UV Index value of 2, and less, symbolizes a low health risk from the exposure to the Sun's UV rays for ordinary individuals.
Note: The average daily UV index of 1 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 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 Boise?

December is the coldest month in Boise, Idaho, with an average high-temperature of 37.6°F (3.1°C) and an average low-temperature of 24.1°F (-4.4°C).

What is the temperature in December in Boise?

The average high-temperature, in December, in Boise, Idaho, is 37.6°F (3.1°C), while the average low-temperature is 24.1°F (-4.4°C).

What is the average humidity in December in Boise?

The average relative humidity in December is 74.6%.

How much does it rain in Boise in December?

In Boise, in December, during 11.8 rainfall days, 1.6" (39.4mm) of precipitation is typically accumulated.

What is the wettest month in Boise?

December is the month with the most rainfall in Boise, Idaho. Rain falls for 11.8 days and accumulates 1.6" (39.4mm) of precipitation.

How many days does it snow in December in Boise?

In December, in Boise, it is snowing for 6 days. Throughout December, 7" (177.8mm) of snow is accumulated.

What is the snowiest month in Boise?

December is the month with the most snowfall in Boise. Snow falls for 6 days and accumulates 7" (177.8mm) of snow.

What is the month with the shortest days in Boise?

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

What is the average length of the day in December in Boise?

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

What is the month with the least sunshine in Boise?

With an average of 3.4h of sunshine, December has the least sunshine of the year in Boise.

How many hours of sunshine does Boise have in December?

In December, the average sunshine in Boise is 3.4h.

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

Months with the lowest UV index in Boise are January and December, with an average maximum UV index of 1.

What is the UV index reading in December in Boise?

The average daily maximum UV index in December is 1. A UV Index reading of 2, and below, represents a minimal hazard to health from the exposure to the Sun's UV radiation.
Average temperature in December - Boise, ID
  • Average high temperature in December: 3.1°C

The warmest month (with the highest average high temperature) is July (32.9°C).
The month with the lowest average high temperature is December (3.1°C).

  • Average low temperature in December: -4.4°C

The month with the highest average low temperature is July (15.8°C).
The coldest month (with the lowest average low temperature) is December (-4.4°C).

Average humidity in December - Boise, ID
  • Average humidity in December: 74.6%

The month with the highest relative humidity is January (75%).
The month with the lowest relative humidity is July (36.1%).

Average rainfall in December - Boise, ID
  • Average rainfall in December: 39.4mm

The wettest month (with the highest rainfall) is December (39.4mm).
The driest month (with the lowest rainfall) is August (6.1mm).

Average rainfall days in December - Boise, ID
  • Average rainfall days in December: 11.8 days

The month with the highest number of rainy days is December (11.8 days).
The month with the lowest number of rainy days is August (2.4 days).

Average snowfall in December - Boise, ID
  • Average snowfall in December: 177.8mm

The month with the highest snowfall is December (177.8mm).
Months with the lowest snowfall are May, June, July, August and September (0mm).

Average snowfall days in December - Boise, ID
  • Average snowfall days in December: 6 days

The month with the highest number of snowfall days is December (6 days).
Months with the lowest number of snowfall days are May, June, July, August and September (0 days).

Average daylight in December / Average sunshine in December - Boise, ID
  • 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: 3.4h

The month with most sunshine is July (Average sunshine: 12.9h).
The month with least sunshine is December (Average sunshine: 3.4h).

Average UV index in December - Boise, ID
  • Average UV index in December: 1

Months with the highest UV index are June and July (UV index 9).
Months with the lowest UV index are January and December (UV index 1).