If you plan to visit San Sebastian in December, the weather is typically alright, with an average high temperature of +55°F during the day and approximately 5 sunny days. Expect some rainy, though, as there are typically 18 rainy days in the month and around 161 mm of precipitation. The weather is changeable so you may have to pack for every eventuality. Search flightsin one click on Avionero.
Average weather
☀️
+55°F
Avg. max. temperature
+21°F
Min.
+75°F
Max.
161 mm
Total precipitation
77%
Avg. humidity
3 m/s
Avg. wind
5 ☀️
Sunny Days
8 ⛅️
Cloudy
18 🌦
Rainy
Our opinion: San Sebastian has OK weather in December.
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Average temperature in San Sebastian in December
Here are the expected maximum, average and minimum temperatures in San Sebastian for December based on the historical data.
Last Year
Historical Data
Going from a maximum of +70°F during the day to a minimum of +37°F during the night, the temperature in December averages around +59°F.
The average maximum temperature goes up 33% by the end of the month, compared with the beginning of the month, from +52°F to +63°F.
Is San Sebastian warm or cold in December?
San Sebastian is typically mild in December.
Maximum temperatures go down compared to the previous month from +59°F to +55°F. The minimum temperature also goes down from +50°F to +46°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 Sebastian, here is the comparison with other months:
Water temperature in San Sebastian in December
Water in San Sebastian in December is Cold. It varies from +55°F to +61°F, with an average of +58°F.Note that the air temperature is lower than the water temperature, averaging around +55°F.
In December, water temperatures are average relative to the rest of the year:
The warmest water temperatures in San Sebastian are reached in August, when the average sea temperature rises to +70°F. The coldest water temperatures are in February, with an average of +54°F.
Can you swim in San Sebastian in December?
We would not recommend swimming in San Sebastian in December, the water is very cold (+58°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 Sebastian in December
San Sebastian weather looks like this, on average, in December and the surrounding months.
November
December
January
Avg. temperature
+59°F
+55°F
+54°F
Min. temperature
+28°F
+21°F
+21°F
Max. temperature
+84°F
+75°F
+73°F
Rainfall
191 mm
161 mm
161 mm
Wind
3 m/s
3 m/s
3 m/s
Avg. water temperature
+62°F
+58°F
+55°F
Humidity
78%
77%
77%
Air pressure
1017 HPa
1019 HPa
1020 HPa
Sunny days
5
5
4
Cloudy days
6
8
8
Rainy days
18
18
18
Snowy days
0
0
1
December weather is still as ok as in November.It’s getting colder in December. From +59°F in the day, the average maximum temperature lowers to +55°F.As December arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 191 mm to 161 mm.It feels drier, as humidity decreases from 78% to 77%.The average wind speed doesn’t change much during December, staying around 3 m/s.The amount of sunny days stay about the same, averaging 5 sunny days during the month.
January brings much the same weather, it remains ok.
Wind speed in San Sebastian in December based on historical data.
Last Year
Historical Data
The average wind speed is 3 m/s getting up to 7 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in San Sebastian is gradually increasing during December, going from 2 m/s to 4 m/s over the course of the month.
Rain
Amount of rainfall in mm during December in San Sebastian based on historical data.
Last Year
Historical Data
Typically, there is a 61% chance of rain on an average day in December, with total rainfall of approximately 262 mm. The maximum amount of rainfall per day is around 33 mm, which is moderate rain.December is a pretty wet month with over 19 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 Sebastian, here is a comparison with other months, total mm:
San Sebastian wettest month is November, where a typical day has a 60% chance of precipitation and 191 mm of rainfall per day. July, on the other hand, is the driest month with a mere 52% chance of precipitation and 93 mm of rainfall per day.
How was the weather last December in San Sebastian?
This is the weather in San Sebastian in December 2024:
1 December
🌧️
+53°F
2 December
🌧️
+51°F
3 December
☀️
+59°F
4 December
🌧️
+61°F
5 December
🌧️
+54°F
6 December
☀️
+58°F
7 December
☀️
+57°F
8 December
🌧️
+57°F
9 December
☀️
+67°F
10 December
☀️
+70°F
11 December
☁️
+69°F
12 December
🌧️
+65°F
13 December
🌧️
+55°F
14 December
🌧️
+57°F
15 December
☁️
+58°F
16 December
☀️
+56°F
17 December
☀️
+57°F
18 December
☀️
+56°F
19 December
☁️
+53°F
20 December
🌧️
+55°F
21 December
🌧️
+56°F
22 December
🌧️
+56°F
23 December
🌧️
+55°F
24 December
☀️
+57°F
25 December
☀️
+61°F
26 December
☀️
+58°F
27 December
☀️
+61°F
28 December
☁️
+58°F
29 December
🌧️
+59°F
30 December
☀️
+65°F
31 December
🌧️
+62°F
In December 2024 San Sebastian had 13 sunny days, 4 cloudy days, and 14 rainy days. The average maximum temperature was +59°F, with an absolute maximum of +70°F and a minimum of +50°F. The average humidity was 82%, with a maximum of 98% and a minimum of 52%. The average wind speed was 3 m/s, with a maximum of 10 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 Sebastian climate has changed over the last 43 years.
The climate in San Sebastian in December has not changed that much over the last 43 years.
The average temperature was the lowest in 1984 (+61°F) and the highest in 2022 (+68°F). The driest year was 1989 with only 973 mm of rainfall, and the wettest year was 2019 with 4351 mm.
FAQ
Frequently asked questions about the weather in San Sebastian in December:
Is December a good time to visit San Sebastian?
It’s always a good time to visit San Sebastian, 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 Sebastian in December?
December has mild temperatures in San Sebastian. 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 Sebastian in December?
Swimming in San Sebastian in December is challenging and not recommended for inexperienced swimmers or without proper equipment and preparation.
Is San Sebastian rainy in December?
San Sebastian 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 Sebastian in December?
Usually, it’s not very sunny in San Sebastian 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 Sebastian, 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.
