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
December is the coldest month, with the temperature often reaching an average high of 55.8°F (13.2°C) and an average low of 40.1°F (4.5°C).Humidity
The average relative humidity in December is 72%.Rainfall
December is the month with the most rainfall in San Martin, California. Rain falls for 9.7 days and accumulates 1.97" (50mm) of precipitation.Daylight
December has the shortest days of the year in San Martin, with an average of 9h and 42min of daylight.On the first day of the month, sunrise is at 7:01 am and sunset at 4:49 pm. On the last day of December, sunrise is at 7:19 am and sunset at 4:59 pm PST.
Sunshine
With an average of 6h 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 reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the ordinary person.Note: In December, the UV index of 3 transforms into the following advice:
Exercise prevention - Warding off sunburn is urged. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What time of the year is the coldest?
What are December temperatures?
What is the average humidity in December?
What is the wettest month?
How many days does it rain in December in San Martin?
What is the month with the shortest days?
How many hours of daylight does San Martin have in December?
When is the sunrise / sunset in December?
What is the month with the least sunshine?
How many hours of sunshine does San Martin have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
San Martin, CA
- Average high temperature in December: 55.8°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The month with the lowest average high temperature is December (55.8°F).
- Average low temperature in December: 40.1°F
The month with the highest average low temperature is August (55°F).
The coldest month (with the lowest average low temperature) is December (40.1°F).
Average pressure in December
San Martin, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in December
San Martin, CA
- Average wind speed in December: 4.1mph
The windiest month (with the highest average wind speed) is May (5.4mph).
The calmest month (with the lowest average wind speed) is November (3.9mph).
Average humidity in December
San Martin, CA
- Average humidity in December: 72%
The month with the highest relative humidity is March (74%).
The months with the lowest relative humidity are July and September (55%).
Average rainfall in December
San Martin, CA
- Average rainfall in December: 1.97"
The wettest month (with the highest rainfall) is December (1.97").
The driest months (with the least rainfall) are June, July and August (0.08").
Average rainfall days in December
San Martin, CA
- Average rainfall days in December: 9.7 days
The month with the highest number of rainy days is March (12.4 days).
The month with the least rainy days is August (1 days).
Average daylight in December /
Average sunshine in December
San Martin, 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 42min).
- Average sunshine in December: 6h and 0min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in December
San Martin, CA
- Average sunshine days in December: 20.5 days
The month with the most sunshine days is August (28.7 days).
The month with the least sunshine days is March (16.8 days).
Average UV index in December
San Martin, CA
- Average UV index in December: 3
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
San Martin, CA
- Average cloud cover in December: 34
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 5).
Average visibility in December
San Martin, 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).
San Martin, California, USA
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