San Diego weather in December
“Mild and bright — an underrated time to visit.”
Roughly 5 rainy days across the month, on average.
In december, San Diego settles into its kind, mild rhythm. The city keeps a different pulse than in summer or midwinter, and travellers who arrive with the right expectations are rewarded.
Days average around 18°C (65°F), cooling to 9°C after sunset. Rainfall is moderate — around 5 rainy days spread through the month. Long days of sunshine reward early starts.
These figures are climatological averages, drawn from a decade of daily records via the Open-Meteo Archive — not a forecast. But they are honest, and they are the sort of thing a good travel guide ought to tell you before you book the flight.
What to pack for San Diego in December
- •A light layer for cool mornings and evenings
- •A merino base layer for the cold evenings
- •Comfortable, broken-in walking shoes
- •A small daypack that won't look like a tourist beacon
What to pack for San Diego in December
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Where to stay in San Diego
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Compare hotels on Booking.com→December vs. the rest of the year
How this month compares in San Diego. Tap any month to read more.
highlighted months are among the best time to visit.
Best time to visit San Diego
While December has its own character in San Diego, the data-backed best months to visit San Diego are April, June, July, August. These months combine the most favourable temperatures, rainfall, and sunshine across a ten-year climate record.
See the full best-time-to-visit guide for San DiegoOther places with a similar climate right now
San Diego in December — FAQ
Q01Is December a good time to visit San Diego?
Is December a good time to visit San Diego?
Yes — it is a good time to visit, with pleasant, comfortable weather. In December, San Diego averages a high of 18°C (65°F) and a low of 9°C (49°F), with 52mm of rainfall across roughly 5 rainy days.
Q02What is the average temperature in San Diego in December?
What is the average temperature in San Diego in December?
The average high temperature in San Diego during December is 18°C (65°F), with an average low of 9°C (49°F). These figures are averaged from ten years of daily records (2015–2024, Open-Meteo Archive).
Q03How many rainy days does San Diego have in December?
How many rainy days does San Diego have in December?
San Diego averages approximately 5 rainy days in December, with a total monthly rainfall of about 52mm. This is based on daily precipitation records where days with 1mm or more of rain are counted as rainy days.
Q04What should I pack for San Diego in December?
What should I pack for San Diego in December?
For San Diego in December, pack layered clothing for changing temperatures, a merino base layer for evenings, comfortable walking shoes. These recommendations are based on the ten-year weather averages for this specific month.
Q05How crowded is San Diego in December?
How crowded is San Diego in December?
Tourist crowds in San Diego during December are typically moderate. Consider this when planning accommodation — prices track crowd levels closely.