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 stands out as San Gregorio's coldest month, with temperatures ranging between an average high of 55.8°F (13.2°C) and a low of 47.1°F (8.4°C).Humidity
In December, the average relative humidity is 72%.Rainfall
In San Gregorio, in December, during 8.9 rainfall days, 0.79" (20mm) of precipitation is typically accumulated. Throughout the year, there are 57.5 rainfall days, and 4.76" (121mm) 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 7:05 am and sunset at 4:52 pm. On the last day of December, sunrise is at 7:23 am and sunset at 5:02 pm PST.
Sunshine
The month with the least sunshine is December, with an average of 5.9h of sunshine.UV index
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 medium health hazard from unsafe exposure to UV radiation for the average person.Note: The maximum UV index, 3 during December, leads to the following recommendations:
Adopt protective measures - Suggestions to resist sunburn are offered. When the Sun is at its strongest around midday, find shade and limit exposure. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What time of the year is the coldest?
What is the average December temperature?
What is the average humidity in December?
How much does it rain in December?
What is the month with the shortest days?
What is the average length of the day in December?
What time are sunrise and sunset in December?
What is the month with the least sunshine in San Gregorio?
How many hours of sunshine does San Gregorio have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
San Gregorio, CA
- Average high temperature in December: 55.8°F
The warmest month (with the highest average high temperature) is August (73°F).
The month with the lowest average high temperature is December (55.8°F).
- Average low temperature in December: 47.1°F
The months with the highest average low temperature are August and September (56.7°F).
The coldest months (with the lowest average low temperature) are January and February (46.4°F).
Average pressure in December
San Gregorio, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in December
San Gregorio, CA
- Average wind speed in December: 6.6mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in December
San Gregorio, CA
- Average humidity in December: 72%
The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is October (68%).
Average rainfall in December
San Gregorio, CA
- Average rainfall in December: 0.79"
The wettest month (with the highest rainfall) is February (0.98").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in December
San Gregorio, CA
- Average rainfall days in December: 8.9 days
The month with the highest number of rainy days is March (10.6 days).
The month with the least rainy days is June (0.9 days).
Average daylight in December /
Average sunshine in December
San Gregorio, 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: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 54min).
Average sunshine days in December
San Gregorio, CA
- Average sunshine days in December: 20.4 days
The months with the most sunshine days are June and July (26.3 days).
The month with the least sunshine days is March (18.3 days).
Average UV index in December
San Gregorio, CA
- Average UV index in December: 3
The months with the highest UV index are June, July, August and September (UV index 5).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in December
San Gregorio, CA
- Average cloud cover in December: 33
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 9).
Average visibility in December
San Gregorio, 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 Gregorio, California, USA
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