Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December, characterized by an average high temperature of 38.3°F (3.5°C) and a low temperature of 28.6°F (-1.9°C), is generally the coldest month.Humidity
In Startup, the average relative humidity in December is 87%.Rainfall
In December, the rain falls for 19.9 days. Throughout December, 7.48" (190mm) of precipitation is accumulated. In Startup, Washington, during the entire year, the rain falls for 200.6 days and collects up to 51.65" (1312mm) of precipitation.Snowfall
January through April, November and December are months with snowfall in Startup. In Startup, Washington, in December, snow falls for 3 days, with typically accumulated 1.65" (42mm) of snow. In Startup, Washington, during the entire year, snow falls for 15.9 days and aggregates up to 14.41" (366mm) of snow.Daylight
With an average of 8h and 30min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:36 am and sunset at 4:16 pm. On the last day of the month, sunrise is at 7:56 am and sunset at 4:24 pm PST.
Sunshine
January and December, with an average of 3.7h of sunshine, are months with the least sunshine.UV index
January through April, October through 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 unsafe exposure to UV radiation for the ordinary person.Note: In December, the maximum UV index of 2 translates into these guidelines:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Frequently asked questions
What is the coldest time of year in Startup?
Is it cold in Startup during December?
What is the average humidity in December in Startup?
How many days does it rain in December in Startup?
How much does it snow in Startup in December?
What is the month with the shortest days in Startup?
What is the average length of the day in December in Startup?
What time are sunrise and sunset in December in Startup?
What are the months with the least sunshine in Startup?
How many hours of sunshine does Startup have in December?
What are the months with the lowest UV index in Startup?
How high is the UV index in December in Startup?
Average temperature in December
Startup, WA
- Average high temperature in December: 38.3°F
The warmest month (with the highest average high temperature) is August (73.4°F).
The month with the lowest average high temperature is December (38.3°F).
- Average low temperature in December: 28.6°F
The month with the highest average low temperature is August (48°F).
The coldest month (with the lowest average low temperature) is December (28.6°F).
Average pressure in December
Startup, WA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is August (29.99"Hg).
Average wind speed in December
Startup, WA
- Average wind speed in December: 4.4mph
The windiest month (with the highest average wind speed) is January (4.8mph).
The calmest month (with the lowest average wind speed) is August (3.2mph).
Average humidity in December
Startup, WA
- Average humidity in December: 87%
The months with the highest relative humidity are January, February and March (88%).
The month with the lowest relative humidity is July (72%).
Average rainfall in December
Startup, WA
- Average rainfall in December: 7.48"
The wettest month (with the highest rainfall) is January (7.8").
The driest month (with the least rainfall) is August (0.79").
Average rainfall days in December
Startup, WA
- Average rainfall days in December: 19.9 days
The month with the highest number of rainy days is March (22.3 days).
The month with the least rainy days is August (7.9 days).
Average snowfall in December
Startup, WA
- Average snowfall in December: 1.65"
The month with the highest snowfall is February (5.43").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Startup, WA
- 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, September and October (0 days).
Average daylight in December /
Average sunshine in December
Startup, WA
- Average daylight in December: 8h and 3min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 3h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The months with the least sunshine are January and December (Average sunshine: 3h and 42min).
Average sunshine days in December
Startup, WA
- Average sunshine days in December: 9.4 days
The month with the most sunshine days is August (19.9 days).
The month with the least sunshine days is March (7 days).
Average UV index in December
Startup, WA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in December
Startup, WA
- Average cloud cover in December: 61
The months with the most cloud cover are March and December (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in December
Startup, WA
- Average visibility in December: 4mi
The months with the highest visibility are May, June, July, August, September and October (5mi).
The months with the lowest visibility are January, February, March, April, November and December (4mi).
Startup, Washington, USA
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