December weather forecastGeyserville, CA
December
Weather in December
The first month of the winter, December, is still a cool month in Geyserville, California, with an average temperature ranging between min 40.1°F (4.5°C) and max 55°F (12.8°C).Temperature
The month of December, characterized by an average high of 55°F (12.8°C) and a low of 40.1°F (4.5°C), is recognized as the coldest.Humidity
In December, the average relative humidity is 74%.Rainfall
In December, the rain falls for 11.5 days. Throughout December, 3.43" (87mm) of precipitation is accumulated. In Geyserville, during the entire year, the rain falls for 81.2 days and collects up to 19.84" (504mm) of precipitation.Snowfall
In Geyserville, snow does not fall in January, March through December.Daylight
With an average of 9h and 30min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:11 am and sunset at 4:50 pm. On the last day of December, sunrise is at 7:29 am and sunset at 5:00 pm PST.
Sunshine
December has the least sunshine of the year, with an average of 5.6h of sunshine.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index estimate of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The maximum daily UV index of 3 in December interprets into the following recommendations:
Take precautions - Protection against sunburn is recommended. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Geyserville, CA
- Average high temperature in December: 55°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is December (55°F).
- Average low temperature in December: 40.1°F
The month with the highest average low temperature is August (55°F).
The coldest month (with the lowest average low temperature) is December (40.1°F).
Average pressure in December
Geyserville, CA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in December
Geyserville, CA
- Average wind speed in December: 4.7mph
The windiest months (with the highest average wind speed) are April and May (6.2mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).
Average humidity in December
Geyserville, CA
- Average humidity in December: 74%
The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is September (57%).
Average rainfall in December
Geyserville, CA
- Average rainfall in December: 3.43"
The wettest month (with the highest rainfall) is February (4.33").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in December
Geyserville, CA
- Average rainfall days in December: 11.5 days
The month with the highest number of rainy days is March (14.2 days).
The month with the least rainy days is August (0.8 days).
Average snowfall in December
Geyserville, CA
- Average snowfall in December: 0"
The month with the highest snowfall is February (0.04").
The months with the least snowfall are January, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in December
Geyserville, CA
- Average snowfall days in December: 0 days
The month with the highest number of snowfall days is February (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in December /
Average sunshine in December
Geyserville, CA
- Average daylight in December: 9h and 30min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in December: 5h and 36min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in December
Geyserville, CA
- Average sunshine days in December: 18.6 days
The month with the most sunshine days is July (29.8 days).
The month with the least sunshine days is March (14.8 days).
Average UV index in December
Geyserville, CA
- Average UV index in December: 3
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
Geyserville, CA
- Average cloud cover in December: 38
The month with the most cloud cover is March (Cloud cover 41).
The months with the least cloud cover are July and August (Cloud cover 6).
Average visibility in December
Geyserville, CA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
