December weather forecastSan Antonio Heights, CA
December
Weather in December
The first month of the winter, December, is also an enjoyable month in San Antonio Heights, California, with an average temperature ranging between min 45.5°F (7.5°C) and max 62.1°F (16.7°C).Temperature
December, with its average high-temperature of 62.1°F (16.7°C) and an average low-temperature of 45.5°F (7.5°C), holds the record as the coldest month.Humidity
In December, the average relative humidity is 51%.Rainfall
In San Antonio Heights, during December, the rain falls for 6.4 days and regularly aggregates up to 1.69" (43mm) of precipitation. Throughout the year, there are 49.6 rainfall days, and 7.8" (198mm) of precipitation is accumulated.Snowfall
January, March through December are months without snowfall.Daylight
The month with the shortest days is December, with an average of 9h and 54min of daylight.On the first day of December, sunrise is at 6:38 am and sunset at 4:41 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 4:51 pm PST.
Sunshine
The months with the least sunshine are February and December, with an average of 6.9h of sunshine.UV index
December is the month with the lowest UV index, with an average maximum UV index of 3. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: An average maximum UV index of 3 in December leads to these recommendations:
Take necessary precautions - Defending against sun damage is advocated. To protect against the Sun's most potent rays, avoid direct exposure around midday. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
San Antonio Heights, CA
- Average high temperature in December: 62.1°F
The warmest month (with the highest average high temperature) is August (91°F).
The month with the lowest average high temperature is December (62.1°F).
- Average low temperature in December: 45.5°F
The month with the highest average low temperature is August (65.8°F).
The coldest month (with the lowest average low temperature) is December (45.5°F).
Average pressure in December
San Antonio Heights, CA
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in December
San Antonio Heights, CA
- Average wind speed in December: 5.2mph
The windiest months (with the highest average wind speed) are April and May (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.4mph).
Average humidity in December
San Antonio Heights, CA
- Average humidity in December: 51%
The months with the highest relative humidity are March and May (54%).
The month with the lowest relative humidity is August (42%).
Average rainfall in December
San Antonio Heights, CA
- Average rainfall in December: 1.69"
The wettest month (with the highest rainfall) is February (1.77").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in December
San Antonio Heights, CA
- Average rainfall days in December: 6.4 days
The month with the highest number of rainy days is March (7.1 days).
The month with the least rainy days is June (1.2 days).
Average snowfall days in December
San Antonio Heights, 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
San Antonio Heights, 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 February and December (Average sunshine: 6h and 54min).
Average sunshine days in December
San Antonio Heights, CA
- Average sunshine days in December: 23.2 days
The month with the most sunshine days is June (28.2 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in December
San Antonio Heights, CA
- Average UV index in December: 3
The months with the highest UV index are July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in December
San Antonio Heights, CA
- Average cloud cover in December: 21
The month with the most cloud cover is December (Cloud cover 21).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in December
San Antonio Heights, 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).





