San Ysidro Weather in December

December in San Ysidro brings pleasant temperatures, with highs of 19°C (66°F) and nights dropping to 8°C (46°F). It's the rainiest month of the year, so come prepared with waterproof gear.

Rainfall in San Ysidro in December

It's the month with the heaviest rainfall, so an umbrella is a must to navigate the wet weather. Expect around 8 days of rain based on historical data, with 58 mm (2.3 in) average. Rainfall intensity is on the higher side this month. Expect more substantial showers rather than light, passing rain.

Temperature in San Ysidro in December

Temperatures in San Ysidro in December top out at 19°C (66°F) and drop to 8°C (46°F) overnight. Temperatures can feel cooler in the morning and evening, so layering is often the best approach. Nights fall to 8°C (46°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep. Typically, this month presents some of the milder temperatures of the year, yet it remains pleasantly warm.

Sunshine in San Ysidro in December

With approximately 248 hours of sunshine, the days are filled with clear skies. It makes it a perfect month for being outside.

If you prefer dry days with pleasant temperatures, December may not be the ideal month to visit San Ysidro. Our weather planner can help you explore destinations with more pleasant weather conditions.