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 sea temperature 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
December
Weather in December
Temperature
The month of December, characterized by an average high of 62.6°F (17°C) and a low of 50.4°F (10.2°C), is recognized as the coldest.Humidity
In San Clemente, the average relative humidity in December is 63%.Rainfall
December is the month with the most rainfall. Rain falls for 4.8 days and accumulates 0.71" (18mm) of precipitation.Ocean temperature
In San Clemente, in December, the average water temperature is 60.4°F (15.8°C).Note: Swimming is not a pleasurable activity for the majority in water at 60.4°F (15.8°C). Breathing control gets harder as the water temperature dips from 69.8°F (21°C) to 59°F (15°C).
Daylight
The month with the shortest days is December, with an average of 10h and 0min of daylight.On the first day of December in San Clemente, sunrise is at 6:36 am and sunset at 4:42 pm. On the last day of the month, 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 6.5h of sunshine.UV index
January through March, November and December, with an average maximum UV index of 4, are months with the lowest UV index. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: A maximum UV index of 4 in December translates into the following recommendations:
Exercise prevention - Precautions against solar damage are endorsed. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What time of the year is the coldest in San Clemente?
What is the average December temperature?
What is the average humidity in December?
What is the rainiest month?
How many days does it rain in December in San Clemente?
What is the ocean temperature in December?
What is the month with the shortest days?
What is the average length of the day in December?
When is the sunrise / sunset in December?
What is the month with the least sunshine?
How long on average sun shines in December?
What are the months with the lowest UV index?
How high is the UV index in December?
Average temperature in December
San Clemente, CA
- Average high temperature in December: 62.6°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 (62.6°F).
- Average low temperature in December: 50.4°F
The months with the highest average low temperature are August and September (63.5°F).
The coldest month (with the lowest average low temperature) is February (49.6°F).
Average pressure in December
San Clemente, CA
- Average pressure in December: 30.06"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 Clemente, CA
- Average wind speed in December: 5.5mph
The windiest month (with the highest average wind speed) is April (6.2mph).
The calmest months (with the lowest average wind speed) are August and September (4.9mph).
Average humidity in December
San Clemente, CA
- Average humidity in December: 63%
The month with the highest relative humidity is June (75%).
The month with the lowest relative humidity is November (60%).
Average rainfall in December
San Clemente, CA
- Average rainfall in December: 0.71"
The wettest month (with the highest rainfall) is December (0.71").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days in December
San Clemente, CA
- Average rainfall days in December: 4.8 days
The month with the highest number of rainy days is March (7.3 days).
The month with the least rainy days is June (1.4 days).
Average sea temperature in December
San Clemente, CA
- Average sea temperature in December: 60.3°F
The best month for swimming (with the highest average sea temperature) is August (68.3°F).
The coldest months (with the lowest average sea temperature) are January and February (58.9°F).
Average daylight in December /
Average sunshine in December
San Clemente, 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 3min
The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The month with the least sunshine is December (Average sunshine: 6h and 30min).
Average sunshine days in December
San Clemente, CA
- Average sunshine days in December: 24.3 days
The month with the most sunshine days is October (26 days).
The month with the least sunshine days is February (21.6 days).
Average UV index in December
San Clemente, 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 Clemente, CA
- Average cloud cover in December: 26
The months with the most cloud cover are March and May (Cloud cover 27).
The month with the least cloud cover is August (Cloud cover 11).
Average visibility in December
San Clemente, 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).