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 is the month when Sumner sees the lowest average temperatures, with a high of 41.4°F (5.2°C) and a low of 32°F (0°C).Humidity
In Sumner, the average relative humidity in December is 86%.Rainfall
The month with the most rainfall is December, when the rain falls for 19.3 days and typically aggregates up to 5.35" (136mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In Sumner, during December, snow falls for 2.9 days and regularly aggregates up to 1.26" (32mm) of snow. In Sumner, during the entire year, snow falls for 15.8 days and aggregates up to 9.09" (231mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 36min of daylight.On the first day of December in Sumner, sunrise is at 7:35 am and sunset at 4:20 pm. On the last day of the month, sunrise is at 7:55 am and sunset at 4:29 pm PST.
Sunshine
The month with the least sunshine is December, with an average of 4.2h of sunshine.UV index
The months with the lowest UV index are January, February, October through December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a minimal health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The average daily UV index of 2 in December transforms into the following instructions:
Babies, children, and those with sensitive skin should always avoid extended periods in the sun. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Alert! The snow's reflection can amplify the UV radiation of the Sun nearly twice.
Frequently asked questions
What is the coldest time of year in Sumner?
Is it cold in Sumner during December?
What is the average humidity in December in Sumner?
What is the wettest month in Sumner?
How much does it rain in Sumner in December?
How many days does it snow in December in Sumner?
What is the month with the shortest days in Sumner?
What is the average length of the day in December in Sumner?
What time are sunrise and sunset in December in Sumner?
What is the month with the least sunshine in Sumner?
How many hours of sunshine does Sumner have in December?
When is the lowest UV index in Sumner?
What is the UV index reading in December in Sumner?
Average temperature in December
Sumner, WA
- Average high temperature in December: 41.4°F
The warmest month (with the highest average high temperature) is August (75.7°F).
The month with the lowest average high temperature is December (41.4°F).
- Average low temperature in December: 32°F
The month with the highest average low temperature is August (50.9°F).
The coldest month (with the lowest average low temperature) is December (32°F).
Average pressure in December
Sumner, WA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in December
Sumner, WA
- Average wind speed in December: 4.5mph
The windiest month (with the highest average wind speed) is January (4.9mph).
The calmest month (with the lowest average wind speed) is August (3.5mph).
Average humidity in December
Sumner, WA
- Average humidity in December: 86%
The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are July and August (70%).
Average rainfall in December
Sumner, WA
- Average rainfall in December: 5.35"
The wettest month (with the highest rainfall) is December (5.35").
The driest month (with the least rainfall) is July (0.51").
Average rainfall days in December
Sumner, WA
- Average rainfall days in December: 19.3 days
The month with the highest number of rainy days is March (20.7 days).
The month with the least rainy days is August (6.8 days).
Average snowfall in December
Sumner, WA
- Average snowfall in December: 1.26"
The month with the highest snowfall is February (3.31").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Sumner, WA
- Average snowfall days in December: 2.9 days
The month with the highest number of snowfall days is February (5.3 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
Sumner, WA
- Average daylight in December: 8h and 4min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in December: 4h and 1min
The month with the most sunshine is August (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 4h and 12min).
Average sunshine days in December
Sumner, WA
- Average sunshine days in December: 10.1 days
The month with the most sunshine days is August (22 days).
The month with the least sunshine days is February (8.2 days).
Average UV index in December
Sumner, 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, October, November and December (UV index 2).
Average cloud cover in December
Sumner, WA
- Average cloud cover in December: 56
The months with the most cloud cover are January and December (Cloud cover 56).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in December
Sumner, WA
- Average visibility in December: 4mi
The months with the highest visibility are July and August (6mi).
The months with the lowest visibility are January, February and December (4mi).
Sumner, Washington, USA
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