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 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
With an average high-temperature of 55.4°F (13°C) and an average low-temperature of 44.6°F (7°C), December is the coldest month.Humidity
The average relative humidity in December is 71%.Rainfall
In December, the rain falls for 7.5 days. Throughout December, 0.87" (22mm) of precipitation is accumulated. Throughout the year, there are 55.6 rainfall days, and 5.24" (133mm) of precipitation is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 36min of daylight.On the first day of the month, sunrise is at 7:06 am and sunset at 4:50 pm. On the last day of December, sunrise is at 7:24 am and sunset at 5:00 pm PST.
Sunshine
With an average of 5.8h of sunshine, December has the least sunshine of the year.UV index
January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for average individuals.Note: In December, a daily maximum UV index of 3 leads to the following instructions:
Take precautions - Protection against skin and eye damage is obliged. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What month is the coldest?
What are the temperatures in December?
What is the average humidity in December?
How much does it rain in December?
What is the month with the shortest days?
How many hours of daylight does Piedmont have in December?
When is the sunrise / sunset in December?
What is the month with the least sunshine in Piedmont?
How many hours of sunshine does Piedmont have in December?
What are the months with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Piedmont, CA
- Average high temperature in December: 55.4°F
The warmest month (with the highest average high temperature) is September (76.6°F).
The month with the lowest average high temperature is December (55.4°F).
- Average low temperature in December: 44.6°F
The month with the highest average low temperature is September (56.8°F).
The coldest month (with the lowest average low temperature) is January (44.2°F).
Average pressure in December
Piedmont, CA
- Average pressure in December: 30.11"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
Piedmont, CA
- Average wind speed in December: 5.7mph
The windiest month (with the highest average wind speed) is May (7.3mph).
The calmest month (with the lowest average wind speed) is November (5mph).
Average humidity in December
Piedmont, CA
- Average humidity in December: 71%
The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is October (64%).
Average rainfall in December
Piedmont, CA
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is February (1.1").
The driest months (with the least rainfall) are June, July, August and September (0.08").
Average rainfall days in December
Piedmont, CA
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is March (8.7 days).
The month with the least rainy days is August (1.5 days).
Average daylight in December /
Average sunshine in December
Piedmont, CA
- Average daylight in December: 9h and 4min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in December
Piedmont, CA
- Average sunshine days in December: 22.1 days
The month with the most sunshine days is October (26 days).
The month with the least sunshine days is February (20.5 days).
Average UV index in December
Piedmont, CA
- Average UV index in December: 3
The months with the highest UV index are April, May, June, July, August and September (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
Piedmont, CA
- Average cloud cover in December: 35
The month with the most cloud cover is March (Cloud cover 36).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in December
Piedmont, 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).
Piedmont, California, USA
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