If you plan to visit San Francisco in December, the weather is typically alright, with an average high temperature of +57°F during the day and approximately 6 sunny days. Expect some rainy, though, as there are typically 12 rainy days in the month and around 117 mm of precipitation. The weather is changeable so you may have to pack for every eventuality. Search flightsin one click on Avionero.
Average weather
☀️
+57°F
Avg. max. temperature
+25°F
Min.
+73°F
Max.
117 mm
Total precipitation
81%
Avg. humidity
2 m/s
Avg. wind
6 ☀️
Sunny Days
12 ⛅️
Cloudy
12 🌦
Rainy
Our opinion: San Francisco has OK weather in December.
Average temperature in San Francisco in December
Here are the expected maximum, average and minimum temperatures in San Francisco for December based on the historical data.
Last Year
Historical Data
Going from a maximum of +64°F during the day to a minimum of +39°F during the night, the temperature in December averages around +61°F.
The average maximum temperature goes down 7% by the end of the month, compared with the beginning of the month, from +61°F to +59°F.
Is San Francisco warm or cold in December?
San Francisco is typically mild in December.
Maximum temperatures go down compared to the previous month from +63°F to +57°F. The minimum temperature also goes down from +48°F to +45°F.
Pack a light jacket as it will be warm in the day and cool in the evenings.
December is one of the coolest months in San Francisco, here is the comparison with other months:
Water temperature in San Francisco in December
Water in San Francisco in December is Cold. It varies from +52°F to +56°F, with an average of +54°F.This is almost similar to the air temperature, which averages +57°F.
In December, water temperatures are average relative to the rest of the year:
The warmest water temperatures in San Francisco are reached in September, when the average sea temperature rises to +57°F. The coldest water temperatures are in June, with an average of +52°F.
Can you swim in San Francisco in December?
We would not recommend swimming in San Francisco in December, the water is very cold (+54°F on average). Consider swimming only if you are an experienced cold-water swimmer with proper gear.
🦭
Cold
Below +61°F
🏄♂️
Fresh
61°F - 70°F
🏊
Comfortable
70°F - 77°F
👙
Warm
77°F - 82°F
🔥
Very warm
+82°C and up
You will need a full-body wetsuit, cap, gloves, a warm change of clothes, and a hot drink ready for after your swim.
Climate in San Francisco in December
San Francisco weather looks like this, on average, in December and the surrounding months.
November
December
January
Avg. temperature
+63°F
+57°F
+57°F
Min. temperature
+36°F
+25°F
+30°F
Max. temperature
+81°F
+73°F
+75°F
Rainfall
63 mm
117 mm
113 mm
Wind
2 m/s
2 m/s
2 m/s
Avg. water temperature
+55°F
+54°F
+53°F
Humidity
80%
81%
82%
Air pressure
1017 HPa
1018 HPa
1018 HPa
Sunny days
7
6
5
Cloudy days
13
12
14
Rainy days
10
12
13
Snowy days
0
0
0
December weather is still as ok as in November.It’s getting colder in December. From +63°F in the day, the average maximum temperature lowers to +57°F.Prepare for more rain. Average rainfall goes from 63 mm to 117 mm.Humidity rises from 80% to 81%.The average wind speed doesn’t change much during December, staying around 2 m/s.The days becoming less sunny, going from 7 sunny days in November to 6 in December.
January brings much the same weather, it remains ok.
Wind speed in San Francisco in December based on historical data.
Last Year
Historical Data
The average wind speed is 2 m/s getting up to 3 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in San Francisco is gradually decreasing during December, going from 2 m/s to 1 m/s over the course of the month.
Rain
Amount of rainfall in mm during December in San Francisco based on historical data.
Last Year
Historical Data
Typically, there is a 42% chance of rain on an average day in December, with total rainfall of approximately 186 mm. The maximum amount of rainfall per day is around 52 mm, which is considered heavy rain.December is a pretty wet month with over 13 rainy days, so don’t forget to pack an umbrella, raincoat, and a pair of wellies.
December is one of the rainiest months in San Francisco, here is a comparison with other months, total mm:
San Francisco wettest month is December, where a typical day has a 39% chance of precipitation and 117 mm of rainfall per day. July, on the other hand, is the driest month with a mere 0% chance of precipitation and 0 mm of rainfall per day.
How was the weather last December in San Francisco?
This is the weather in San Francisco in December 2023:
1 December
☀️
+60°F
2 December
🌧️
+61°F
3 December
☁️
+63°F
4 December
☁️
+64°F
5 December
☁️
+62°F
6 December
☁️
+63°F
7 December
☁️
+59°F
8 December
☀️
+59°F
9 December
☀️
+59°F
10 December
☁️
+59°F
11 December
☀️
+60°F
12 December
☁️
+61°F
13 December
☀️
+62°F
14 December
☁️
+60°F
15 December
☁️
+60°F
16 December
☁️
+65°F
17 December
☁️
+65°F
18 December
🌧️
+61°F
19 December
🌧️
+63°F
20 December
🌧️
+61°F
21 December
☁️
+61°F
22 December
☁️
+63°F
23 December
☀️
+62°F
24 December
☁️
+59°F
25 December
☁️
+56°F
26 December
☁️
+56°F
27 December
☁️
+59°F
28 December
🌧️
+64°F
29 December
🌧️
+63°F
30 December
🌧️
+61°F
31 December
☁️
+59°F
In December 2023 San Francisco had 6 sunny days, 18 cloudy days, and 7 rainy days. The average maximum temperature was +61°F, with an absolute maximum of +64°F and a minimum of +57°F. The average humidity was 85%, with a maximum of 100% and a minimum of 47%. The average wind speed was 2 m/s, with a maximum of 7 m/s and a minimum of 0 m/s.
Are you planning a trip in December?
Climate Change Over the Years
This is how San Francisco climate has changed over the last 43 years.
The climate in San Francisco in December has not changed that much over the last 43 years.
The average temperature was the lowest in 1982 (+65°F) and the highest in 2014 (+70°F). The driest year was 2013 with only 127 mm of rainfall, and the wettest year was 1983 with 1162 mm.
FAQ
Frequently asked questions about the weather in San Francisco in December:
Is December a good time to visit San Francisco?
It’s always a good time to visit San Francisco, but the weather is changeable in December, so plan a mix of indoor and outdoor activities and exploring, and pack for every eventuality.
Can you sunbathe in San Francisco in December?
December has mild temperatures in San Francisco. Not ideal for sunbathing, but still good for daytime outdoor activities, but plan for cool evenings. Pack a light jacket and shorts!
Can you swim in San Francisco in December?
Swimming in San Francisco in December is challenging and not recommended for inexperienced swimmers or without proper equipment and preparation.
Is San Francisco rainy in December?
San Francisco is often rainy in December. You may get a bit damp when outside, so pack an umbrella, and maybe even a raincoat.
Is it sunny in San Francisco in December?
Usually, it’s not very sunny in San Francisco in December, often it’s pretty cloudy. Pack for any eventuality; layering can help reduce the number of bulky items needed.
For this page, we’ve looked at the typical weather in San Francisco, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.
