December weather forecastSan Juan Capistrano, CA
December
Weather in December
December, the first month of the winter in San Juan Capistrano, is still a refreshing month, with an average temperature fluctuating between 62.4°F (16.9°C) and 50.5°F (10.3°C).Temperature
San Juan Capistrano notes the coldest temperatures in December, with a high average of 62.4°F (16.9°C) and a low of 50.5°F (10.3°C).Humidity
In December, the average relative humidity is 62%.Rainfall
The month with the most rainfall is December, when the rain falls for 6.8 days and typically aggregates up to 1.85" (47mm) of precipitation.Daylight
The month with the shortest days is December, with an average of 10h and 0min of daylight.On the first day of the month, sunrise is at 6:37 am and sunset at 4:42 pm. On the last day of December, sunrise is at 6:54 am and sunset at 4:53 pm PST.
Sunshine
December has the least sunshine of the year, with an average of 6.4h of sunshine.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: In December, the maximum UV index of 4 translates into these guidelines:
Put precautions into practice - Ensuring skin and eye safety is a necessity. To guard against the harmful effects of the Sun, minimize exposure during midday. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
San Juan Capistrano, CA
- Average high temperature in December: 62.4°F
The warmest month (with the highest average high temperature) is September (77.4°F).
The month with the lowest average high temperature is December (62.4°F).
- Average low temperature in December: 50.5°F
The month with the highest average low temperature is August (63.3°F).
The coldest month (with the lowest average low temperature) is February (50°F).
Average pressure in December
San Juan Capistrano, CA
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in December
San Juan Capistrano, CA
- Average wind speed in December: 5.4mph
The windiest month (with the highest average wind speed) is April (6.3mph).
The calmest months (with the lowest average wind speed) are August, September and October (5mph).
Average humidity in December
San Juan Capistrano, CA
- Average humidity in December: 62%
The month with the highest relative humidity is June (74%).
The month with the lowest relative humidity is November (59%).
Average rainfall in December
San Juan Capistrano, CA
- Average rainfall in December: 1.85"
The wettest month (with the highest rainfall) is December (1.85").
The driest month (with the least rainfall) is June (0.12").
Average rainfall days in December
San Juan Capistrano, CA
- Average rainfall days in December: 6.8 days
The month with the highest number of rainy days is March (7.8 days).
The month with the least rainy days is June (3 days).
Average daylight in December /
Average sunshine in December
San Juan Capistrano, CA
- Average daylight in December: 10h and 0min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in December: 6h and 24min
The month with the most sunshine is August (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 6h and 24min).
Average sunshine days in December
San Juan Capistrano, CA
- Average sunshine days in December: 22.8 days
The month with the most sunshine days is January (24.7 days).
The month with the least sunshine days is May (19.5 days).
Average UV index in December
San Juan Capistrano, CA
- Average UV index in December: 4
The months with the highest UV index are July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).
Average cloud cover in December
San Juan Capistrano, CA
- Average cloud cover in December: 26
The month with the most cloud cover is March (Cloud cover 27).
The month with the least cloud cover is August (Cloud cover 11).
Average visibility in December
San Juan Capistrano, 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).
