Magical Split
The best travel time to Split in Croatia is from May til October and the best months are May, June and September.
Opatija Weather in May
Opatija in May sees pleasant daytime temperatures of 20°C (68°F) and nighttime lows of 12°C (54°F). Rainfall is fairly high this month at around 141 mm (5.6 in), so pack a rain jacket to stay dry.
Rainfall in Opatija in May
You can expect rain on around 15 days based on historical patterns, with 141 mm (5.6 in) average for the month. Wet weather is a regular and significant part of this month. Frequent days of rain combined with high totals means proper waterproofs are worth packing.
Temperature in Opatija in May
Daytime highs in Opatija in May reach 20°C (68°F), with nights around 12°C (54°F). This creates a mild day-to-night pattern that is generally easy to manage with the right clothing. With lows of 12°C (54°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest.
Sunshine in Opatija in May
Enjoy a sunny month with about 234 hours of sunshine, the clear skies make Opatija even more beautiful.
Average water temperature in May
At 18°C (64°F), the water is getting there, comfortable enough for most swimmers, though those used to warmer seas may still find it a touch cool.If you're inclined towards comfortable temperatures and drier conditions, May is a good time to visit Opatija.
Opatija Temperature in May
Min Temperature
12°C (54°F)
Max Temperature
20°C (68°F)
Water Temperature
18°C (64°F) *
Chance of Rain
51%
Precipitation
141 mm (5.6 in)
Rainy days
15 days
Humidity
64% *
Sunshine
234 hours *
Percentage Sunshine
57% *
* Data from: Rijeka, Croatia (7 KM, 4 Miles).
Opatija Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Opatija - and find the best time to visit.
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Opatija typically rise from around 20°C (68°F) at the start of May to approximately 23°C (73°F) by the end. Nights are cool, with lows typically ranging from 11°C (52°F) to 14°C (57°F).
Average temperatures in May
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 May
Historical weather records for Opatija in May
Browse day-by-day weather records for Opatija spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Opatija historical weather extremes in May
According to our 50 years of weather records for Opatija, the following extremes were recorded between 1976 and 2026.
- On May 25, 2009, temperatures climbed to 33°C (91°F), marking the warmest May day on record.
- Opatija experienced its chilliest May day on May 13, 1978, reaching only 9°C (48°F).
- Nighttime temperatures dropped to 4°C (39°F) on May 12, 1978, marking the coldest May night on record.
- The wettest day in May Opatija was on May 4, 2007 with 77 mm (3 in) of precipitation.
Best Places in Croatia in May
Find out more about the weather in Croatia and which places have the best travel conditions in this month. See all of Croatia in May →
perfect weather
pleasant
tolerable
unpleasant
poor
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).
What to Wear in Opatija in May
Pleasant temperatures in May mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Prepare for significant rainfall with proper waterproof clothing and shoes. With water temperatures around 18°C (64°F), the water is quite cold for swimming. You can skip the swimwear unless you're particularly tough. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.
What To Do in Opatija in May
We rated the following activities from 1 (least suitable) to 10 (best) to do.
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Cycling9/10 -
Walking9/10 -
Camping6/10 -
Outdoor sports9/10
Opatija 3-Day Forecast
More climate data for Opatija
Temperature Rainfall Sunshine Humidity Water Temp
See the full Opatija climate overview or explore weather in Croatia.
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