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 of the year, registering average temperatures as high as 63.1°F (17.3°C) and as low as 51.3°F (10.7°C).Humidity
In December, the average relative humidity in Tustin is 59%.Rainfall
The month with the most rainfall in Tustin is December, when the rain falls for 6.5 days and typically aggregates up to 0.87" (22mm) of precipitation.Daylight
With an average of 10h and 0min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 6:38 am and sunset at 4:42 pm. On the last day of December, in Tustin, sunrise is at 6:55 am and sunset at 4:53 pm PST.
Sunshine
December has the least sunshine of the year, with an average of 6.7h of sunshine.UV index
The months with the lowest UV index in Tustin are January through March, November and December, with an average maximum UV index of 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for ordinary individuals.Note: A daily maximum UV index of 4 in December translates into the following instructions:
Prioritize safety - Recommendations to avert sunburn are shared. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the coldest months in Tustin?
What is the usual temperature for Tustin in December?
What is the average humidity in December in Tustin?
What is the wettest month in Tustin?
How much does it rain in Tustin in December?
What is the month with the shortest days in Tustin?
What is the average length of the day in December in Tustin?
When are sunrise and sunset in December in Tustin?
What is the month with the least sunshine in Tustin?
How many hours of sunshine does Tustin have in December?
What are the months with the lowest UV index in Tustin?
What is the UV index reading in December in Tustin?
Average temperature in December
Tustin, CA
- Average high temperature in December: 63.1°F
The warmest month (with the highest average high temperature) is August (80.2°F).
The month with the lowest average high temperature is December (63.1°F).
- Average low temperature in December: 51.3°F
The month with the highest average low temperature is August (65.1°F).
The coldest month (with the lowest average low temperature) is February (50.7°F).
Average pressure in December
Tustin, 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 (29.88"Hg).
Average wind speed in December
Tustin, CA
- Average wind speed in December: 5.2mph
The windiest months (with the highest average wind speed) are April and May (6mph).
The calmest months (with the lowest average wind speed) are August, September and October (4.8mph).
Average humidity in December
Tustin, CA
- Average humidity in December: 59%
The month with the highest relative humidity is June (70%).
The month with the lowest relative humidity is November (55%).
Average rainfall in December
Tustin, CA
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is December (0.87").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in December
Tustin, CA
- Average rainfall days in December: 6.5 days
The month with the highest number of rainy days is March (6.7 days).
The month with the least rainy days is June (1.3 days).
Average daylight in December /
Average sunshine in December
Tustin, CA
- Average daylight in December: 10h and 0min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in December: 6h and 4min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in December
Tustin, CA
- Average sunshine days in December: 23 days
The month with the most sunshine days is June (26.9 days).
The month with the least sunshine days is February (20.3 days).
Average UV index in December
Tustin, CA
- Average UV index in December: 4
The months with the highest UV index are June, 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
Tustin, CA
- Average cloud cover in December: 23
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 6).
Average visibility in December
Tustin, 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).
Tustin, California, USA
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