Opatija weather in December 2026

Q: How warm is it in Opatija in December?

Daytime temperatures usually reach 10°C in Opatija in December, falling to 2°C at night.

Q: How sunny is it in Opatija in December?

There are normally 3 hours of bright sunshine each day in Opatija in December - that's 38% of daylight hours.

Q: How warm is the sea around Opatija in December?

The average sea temperature around Opatija in December is 16°C.

Q: Does it rain in Opatija in December?

There are usually 14 days with some rain in Opatija in December and the average monthly rainfall is 127mm.

Expect daytime maximum temperatures of 45°F in Opatija, Croatia in December based on long-term weather averages. There are 3 hours of sunshine per day on average with 14 days with some rainfall and typically 5.0 inches of rainfall in the month.

45
45°F max day temperature
3
3 hours of sunshine per day
14
14 days with some rainfall
30
30°F min night temperature
9
9 hours of daylight per day
0
No heat & humidity
5.0
5.0 inches of monthly rainfall
1
1 (Low) UV index
55
55°F sea temperature

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The December weather guide for Croatia (Opatija) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C) | Imperial (°F)