Go to Bovec in Slovenia
With mountains that linger in the blue sky, an emerald-green river Bovec offers picturesque scenes that are a must see for your bucket list.
Koper Weather in May
Koper in May sees pleasant daytime temperatures of 21°C (70°F) and nighttime lows of 14°C (57°F). Rainfall is fairly high this month at around 109 mm (4.3 in), so pack a rain jacket to stay dry.
Rainfall in Koper in May
Typically around 14 days of rainfall are expected, averaging 109 mm (4.3 in) for the month. When it rains this month, it tends to come down fairly heavily. Showers can be substantial even if they don't last all day.
Temperature in Koper in May
May in Koper brings pleasant temperatures, with highs of 21°C (70°F) and nights around 14°C (57°F). The difference between afternoon and evening temperatures is usually noticeable. With overnight lows of 14°C (57°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.
Sunshine in Koper in May
The days are predominantly sunny, with an estimated total of around 256 hours of sunshine. These sun-filled days are perfect for playing sports, visiting parks, or going for a bike ride.Should you favor a climate that's both dry and comfortably warm, June, July and August typically offer the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Koper Temperature in May
Min Temperature
14°C (57°F)
Max Temperature
21°C (70°F)
Chance of Rain
47%
Precipitation
109 mm (4.3 in)
Rainy days
14 days
Humidity
54% *
Sunshine
256 hours *
Percentage Sunshine
*
* Data from: Portorož, Slovenia (11 KM, 7 Miles).
Koper Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Koper - and find the best time to visit.
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Koper typically rise from around 20°C (68°F) at the start of May to approximately 24°C (75°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 Koper in May
Browse day-by-day weather records for Koper spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Koper historical weather extremes in May
Our historical data for Koper spans 1976 to 2026, revealing these weather extremes.
- The warmest day in May was on May 28, 2003, with a maximum of 32°C (90°F).
- The lowest daytime temperature in May was 9°C (48°F), recorded on May 13, 1978.
- The coldest night in May in Koper was on May 1, 1976, with a minimum of 3°C (37°F).
- The wettest day in May Koper was on May 8, 2000 with 65 mm (2.6 in) of precipitation.
Best Places in Slovenia in May
Find out more about the weather in Slovenia and which places have the best travel conditions in this month. See all of Slovenia 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 Koper in May
Comfortable temperatures call for an easy wardrobe in May. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Expect heavy rainfall, so bring good rain protection and waterproof bags. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.
What To Do in Koper in May
We rated the following activities from 1 (least suitable) to 10 (best) to do.
-
Cycling9/10 -
Walking9/10 -
Camping6/10 -
Outdoor sports9/10
Koper 3-Day Forecast
More climate data for Koper
Temperature Rainfall Sunshine Humidity
See the full Koper climate overview or explore weather in Slovenia.
Popular in May
Where to go in May - average daytime high across popular destinations.
Maribor
21°C (70°F) Piran21°C (70°F) Ljubljana21°C (70°F) Portorož21°C (70°F) Bled
19°C (66°F) Bohinj
18°C (64°F) Bovec18°C (64°F) Kranjska Gora18°C (64°F) Bucket list
Need travel inspiration? Check out our bucket list articles and be inspired.
Go to Bovec in Slovenia
Experience Dazzling Fairy Tales In The Lake Bled Of Slovenia
Slovenia's most well-known tourist destination is Lake Bled, which is still relatively undiscovered when compared to other European attractions despite its growing notoriety.
The 10 most charming villages in France
Discover France's top 10 beautiful villages. From Normandy to the Côte d'Azur, experience quaint squares and cobbled streets. Which one will you visit this summer?
The train journey from Bucharest to Brasov is one of the most beautiful in Romania
In three hours, you'll get from Bucharest to Brasov by train. It is one of the most beautiful routes in Romania, certainly the most beautiful that can be done by express train.