December weather forecastMount Wilson, CA
December
Weather in December
The first month of the winter, December, is also a moderate month in Mount Wilson, California, with temperature in the range of an average low of 43.3°F (6.3°C) and an average high of 58.5°F (14.7°C).Temperature
December, marked by an average high-temperature of 58.5°F (14.7°C) and a low-temperature of 43.3°F (6.3°C), is the coldest month.Humidity
In December, the average relative humidity is 52%.Rainfall
In Mount Wilson, during December, the rain falls for 5.8 days and regularly aggregates up to 1.69" (43mm) of precipitation. Throughout the year, in Mount Wilson, there are 50.3 rainfall days, and 8.7" (221mm) of precipitation is accumulated.Snowfall
January through April, November and December are months with snowfall. December is the month with the most snowfall in Mount Wilson. Snow falls for 0.5 days and accumulates 2.99" (76mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 54min of daylight.On the first day of the month, sunrise is at 6:40 am and sunset at 4:42 pm. On the last day of December, sunrise is at 6:58 am and sunset at 4:53 pm PST.
Sunshine
January, February and December, with an average of 6.9h of sunshine, are months with the least sunshine.UV index
The months with the lowest UV index are 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 ordinary individuals.Note: An average maximum UV index of 3 in December leads to these recommendations:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Mount Wilson, CA
- Average high temperature in December: 58.5°F
The warmest month (with the highest average high temperature) is August (86.2°F).
The month with the lowest average high temperature is December (58.5°F).
- Average low temperature in December: 43.3°F
The month with the highest average low temperature is August (64°F).
The coldest month (with the lowest average low temperature) is December (43.3°F).
Average pressure in December
Mount Wilson, CA
- Average pressure in December: 30.08"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in December
Mount Wilson, CA
- Average wind speed in December: 5.7mph
The windiest month (with the highest average wind speed) is April (6mph).
The calmest month (with the lowest average wind speed) is September (4.5mph).
Average humidity in December
Mount Wilson, CA
- Average humidity in December: 52%
The month with the highest relative humidity is March (56%).
The month with the lowest relative humidity is August (45%).
Average rainfall in December
Mount Wilson, CA
- Average rainfall in December: 1.69"
The wettest month (with the highest rainfall) is February (1.73").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days in December
Mount Wilson, CA
- Average rainfall days in December: 5.8 days
The month with the highest number of rainy days is March (6.4 days).
The month with the least rainy days is June (1.3 days).
Average snowfall in December
Mount Wilson, CA
- Average snowfall in December: 2.99"
The month with the highest snowfall is December (2.99").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Mount Wilson, CA
- Average snowfall days in December: 0.5 days
The month with the highest number of snowfall days is February (1.3 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
Mount Wilson, CA
- Average daylight in December: 9h and 54min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in December: 6h and 54min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The months with the least sunshine are January, February and December (Average sunshine: 6h and 54min).
Average sunshine days in December
Mount Wilson, CA
- Average sunshine days in December: 23.7 days
The month with the most sunshine days is June (27.9 days).
The month with the least sunshine days is February (21.4 days).
Average UV index in December
Mount Wilson, CA
- Average UV index in December: 3
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are November and December (UV index 3).
Average cloud cover in December
Mount Wilson, CA
- Average cloud cover in December: 22
The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in December
Mount Wilson, 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).
