San Bernardino in December averages 33°C (91°F) during the day and 22°C (72°F) at night. Keep in mind that quite a bit of rainfall is expected this month.
If you prefer dry days with pleasant temperatures, December may not be the ideal month to visit San Bernardino. Our weather planner can help you explore destinations with more pleasant weather conditions.
Min Temperature
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Chance of Rain
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Percentage Sunshine
Pick a month to see the average temperature, rainfall and sunshine in San Bernardino - and find the best time to visit.
50-year average (1976-2025)
Based on our historical records, temperatures in San Bernardino typically stay consistent throughout December, with daily highs averaging around 33°C (91°F). Nights are warm, with lows typically ranging from 21°C (70°F) to 23°C (73°F).
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Browse day-by-day weather records for San Bernardino spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Our historical data for San Bernardino spans 1985 to 2025, revealing these weather extremes.
Find out more about the weather in Paraguay and which places have the best travel conditions in this month. See all of Paraguay in December →
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
Warm but pleasant conditions in San Bernardino in December. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. It's going to pour! Pack a good poncho and prepare for very wet conditions. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Temperature Rainfall Sunshine Humidity
See the full San Bernardino climate overview or explore weather in Paraguay.
Where to go in December - average daytime high across popular destinations.
San Bernardino
33°C (91°F) Areguá33°C (91°F) Asuncion33°C (91°F) Luque33°C (91°F) Encarnación32°C (90°F) Ybycuí32°C (90°F) Villarrica33°C (91°F) Ciudad del Este32°C (90°F) Need travel inspiration? Check out our bucket list articles and be inspired.
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