Olympia
Washington, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Olympia, WA

The calm Capitol Lake overlooking the Washington State Capitol building in Olympia, Washington
The calm Capitol Lake overlooking the Washington State Capitol building in Olympia, Washington
The first month of the winter, December, is also a frosty month in Olympia, Washington, with average temperature ranging between max 44.2°F (6.8°C) and min 32.5°F (0.3°C).

Temperature

With an average high-temperature of 44.2°F (6.8°C) and an average low-temperature of 32.5°F (0.3°C), December is the coldest month.

Humidity

December is the most humid month, with an average relative humidity of 89.1%.

Rainfall

In Olympia, in December, it is raining for 19.6 days, with typically 7.5" (189.5mm) of accumulated precipitation. In Olympia, during the entire year, the rain falls for 162.8 days and collects up to 50" (1270mm) of precipitation.

Snowfall

Months with snowfall in Olympia are January through March, November and December.

Daylight

December has the shortest days of the year, with an average of 8.6h of daylight.

Sunshine

Months with the least sunshine in Olympia, Washington, are January and December, with an average of 2h of sunshine.

UV index

January, November and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low threat to health from the exposure to the Sun's UV radiation for ordinary individuals.
The daily maximum UV index of 1 interpret into the following advice:
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. 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. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the coldest month in Olympia?

The coldest month is December, with an average high-temperature of 44.2°F (6.8°C) and an average low-temperature of 32.5°F (0.3°C).

What is the temperature in December in Olympia?

In December, in Olympia, the average high-temperature is 44.2°F (6.8°C), and the average low-temperature is 32.5°F (0.3°C).

What is the most humid month in Olympia?

With an average relative humidity of 89.1%, December is the most humid month.

What is the average humidity in December in Olympia?

In Olympia, Washington, the average relative humidity in December is 89.1%.

How much does it rain in Olympia in December?

In December, in Olympia, Washington, the rain falls for 19.6 days. Throughout December, 7.5" (189.5mm) of precipitation is accumulated.

How much does it snow in Olympia in December?

In Olympia, in December, snow falls for 2 days, with typically accumulated 2.6" (66mm) of snow.

What is the month with the shortest days in Olympia?

December has the shortest days of the year, with an average of 8.6h of daylight.

How many hours of daylight does Olympia have in December?

The average length of the day in December is 8.6h.

What is the month with the least sunshine in Olympia?

January and December, with an average of 2h of sunshine, are months with the least sunshine.

How long on average sun shines in December in Olympia?

In December, the average sunshine is 2h.

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

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

What is the UV index intensity in December in Olympia?

The average daily maximum UV index in December in Olympia, Washington, is 1. A UV Index reading of 2, and below, represents a minimal hazard to health from unprotected exposure to the UV radiation.
Average temperature in December - Olympia, WA
  • Average high temperature in December: 44.2°F

The warmest month (with the highest average high temperature) is August (77.7°F).
The month with the lowest average high temperature is December (44.2°F).

  • Average low temperature in December: 32.6°F

The month with the highest average low temperature is July (50.8°F).
The coldest month (with the lowest average low temperature) is December (32.6°F).

Average humidity in December - Olympia, WA
  • Average humidity in December: 89.1%

The month with the highest relative humidity is December (89.1%).
The month with the lowest relative humidity is July (70.8%).

Average rainfall in December - Olympia, WA
  • Average rainfall in December: 7.5"

The wettest month (with the highest rainfall) is November (8.6").
The driest month (with the lowest rainfall) is July (0.6").

Average rainfall days in December - Olympia, WA
  • Average rainfall days in December: 19.6 days

The month with the highest number of rainy days is November (20.1 days).
The month with the lowest number of rainy days is July (4.6 days).

Average snowfall in December - Olympia, WA
  • Average snowfall in December: 2.6"

The month with the highest snowfall is February (4.7").
Months with the lowest snowfall are April, May, June, July, August, September and October (0").

Average snowfall days in December - Olympia, WA
  • Average snowfall days in December: 2 days

The month with the highest number of snowfall days is February (2.2 days).
Months with the lowest number of snowfall days are May, June, July, August, September and October (0 days).

Average daylight in December / Average sunshine in December - Olympia, WA
  • Average daylight in December: 8.6h

The month with the longest days is June (Average daylight: 15.8h).
The month with shortest days is December (Average daylight: 8.6h).

  • Average sunshine in December: 2h

The month with most sunshine is July (Average sunshine: 10h).
Months with least sunshine are January and December (Average sunshine: 2).

Average UV index in December - Olympia, WA
  • Average UV index in December: 1

Months with the highest UV index are June, July and August (UV index 7).
Months with the lowest UV index are January, November and December (UV index 1).