Postojna Weather in December
During December, Postojna experiences low daytime temperatures of 5°C (41°F) and cooler nights around -1°C (30°F). As part of the winter season, expect quite a bit of snow/rainfall. Around 125 mm (4.9 in) is typical.
Rainfall in Postojna in December
Climate statistics over the past 30 years suggest around 14 days of snow/rain, with 125 mm (4.9 in) average for the month. The rain this month tends to fall in heavier spells rather than light drizzle. When it rains, showers can be significant.
Temperature in Postojna in December
Daytime temperatures in Postojna reach 5°C (41°F) in December, dropping to -1°C (30°F) at night. December is known for being in the winter season. Temperatures remain on the cold side all day. A proper warm jacket is worth having, not just for evenings. Nights are well below freezing at -1°C (30°F). An extra blanket is a good idea if you feel the cold, especially in older or less well-heated accommodation.
Sunshine in Postojna in December
This month is characterized by fewer sunny days, with about 84 hours of sunshine. It's great for those who appreciate cooler, less sunny days.If you prefer dry days with pleasant temperatures, December may not be the ideal month to visit Postojna. Our weather planner can help you explore destinations with more pleasant weather conditions.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Slovenia, check out our Postojna's climate page.
Postojna Temperature in December
Min Temperature
-1°C (30°F)
Max Temperature
5°C (41°F)
Chance of Rain
47%
Precipitation
125 mm (4.9 in)
Rainy days
14 days
Humidity
67% *
Sunshine
84 hours *
Percentage Sunshine
31% *
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Postojna typically stay consistent throughout December, with daily highs averaging around 5°C (41°F). Nights are cold, with lows typically ranging from -1°C (30°F) to 2°C (36°F).
Average temperatures in December
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in December
Historical weather for Postojna in December
Browse day-by-day weather records for Postojna spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Postojna historical weather extremes in December
According to our 49 years of weather records for Postojna, the following extremes were recorded between 1976 and 2025.
- The warmest day in December was on December 4, 1979, with a maximum of 18°C (64°F).
- The coldest December day was on December 28, 1996, with a maximum of -6°C (21°F).
- The lowest overnight temperature recorded in December was -18°C (0°F) (December 31, 1996).
Best Places in Slovenia in December
Find out more about the weather in Slovenia and which places have the best travel conditions in this month. See all of Slovenia in December →
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What to Wear in Postojna in December
Cold weather calls for smart layering in December. A thermal base layer makes a huge difference in staying warm. Add a wool sweater or fleece, then a wind-resistant outer jacket. Prepare for significant rainfall with proper waterproof clothing and shoes. You can probably leave your sunglasses at home, because sunny days are pretty rare this month.What To Do in Postojna in December
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Slovenia, check out our Postojna's climate page.
Temperature Rainfall Sunshine Humidity
See the full Postojna climate overview or explore weather in Slovenia.
