December weather forecastRochester, WA
December
Weather in December
The first month of the winter, December, is also a wintry month in Rochester, Washington, with an average temperature fluctuating between 33.1°F (0.6°C) and 42.6°F (5.9°C).Temperature
In Rochester, the month of December is known for its lowest average temperatures, reaching a high of 42.6°F (5.9°C) and a low of 33.1°F (0.6°C).Humidity
In Rochester, the average relative humidity in December is 89%.Rainfall
In Rochester, during December, the rain falls for 17.9 days and regularly aggregates up to 3.74" (95mm) of precipitation. In Rochester, during the entire year, the rain falls for 168 days and collects up to 23.94" (608mm) of precipitation.Snowfall
Months with snowfall are January through March, November and December. In Rochester, in December, during 1.2 snowfall days, 0.31" (8mm) of snow is typically accumulated. In Rochester, during the entire year, snow falls for 7.9 days and aggregates up to 4.02" (102mm) of snow.Daylight
December has the shortest days of the year, with an average of 8h and 36min of daylight.On the first day of December in Rochester, sunrise is at 7:37 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:57 am and sunset at 4:34 pm PST.
Sunshine
With an average of 3.5h of sunshine, December has the least sunshine of the year.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index of 2 during December translates into the following directions:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Take into account! The reflection from snow can nearly double the Sun's UV radiation intensity.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rochester, WA
- Average high temperature in December: 42.6°F
The warmest month (with the highest average high temperature) is August (77.4°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in December: 33.1°F
The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (33.1°F).
Average pressure in December
Rochester, WA
- Average pressure in December: 30.08"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.02"Hg).
Average wind speed in December
Rochester, WA
- Average wind speed in December: 4.2mph
The windiest months (with the highest average wind speed) are January, March and November (4.5mph).
The calmest month (with the lowest average wind speed) is September (3.6mph).
Average humidity in December
Rochester, WA
- Average humidity in December: 89%
The month with the highest relative humidity is November (90%).
The month with the lowest relative humidity is July (73%).
Average rainfall in December
Rochester, WA
- Average rainfall in December: 3.74"
The wettest month (with the highest rainfall) is January (3.86").
The driest month (with the least rainfall) is July (0.35").
Average rainfall days in December
Rochester, WA
- Average rainfall days in December: 17.9 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (5.6 days).
Average snowfall in December
Rochester, WA
- Average snowfall in December: 0.31"
The month with the highest snowfall is February (1.54").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Rochester, WA
- Average snowfall days in December: 1.2 days
The month with the highest number of snowfall days is February (2.7 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
Rochester, WA
- Average daylight in December: 8h and 36min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in December: 3h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is December (Average sunshine: 3h and 30min).
Average sunshine days in December
Rochester, WA
- Average sunshine days in December: 10.8 days
The month with the most sunshine days is August (20.9 days).
The months with the least sunshine days are February and March (9.3 days).
Average UV index in December
Rochester, WA
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Rochester, WA
- Average cloud cover in December: 65
The month with the most cloud cover is January (Cloud cover 66).
The months with the least cloud cover are July and August (Cloud cover 38).
Average visibility in December
Rochester, WA
- Average visibility in December: 4mi
The month with the highest visibility is July (5mi).
The months with the lowest visibility are January, February, March, April, May, June, August, September, October, November and December (4mi).
