Postojna Weather in May
May in Postojna typically sees daytime highs of 20°C (68°F) and nighttime lows of 10°C (50°F). Rainfall is also possible this month, so it's worth packing an umbrella.
Rainfall in Postojna in May
Typically around 16 days of rainfall are expected, averaging 143 mm (5.6 in) for the month. This is a wet month with frequent and often heavy showers. Both the number of rain days and the total rainfall are high.
Temperature in Postojna in May
In May, expect pleasant temperatures in Postojna, with highs of 20°C (68°F) and lows of 10°C (50°F) at night. A light jacket or extra layer can be useful, especially outside the warmest hours of the day. Nights fall to 10°C (50°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep.
Sunshine in Postojna in May
The days are predominantly sunny, with an estimated total of around 227 hours of sunshine. These sun-filled days are perfect for playing sports, visiting parks, or going for a bike ride.If you favor pleasant temperatures and minimal rainfall, May is one of the best months to visit Postojna.
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 May
Min Temperature
10°C (50°F)
Max Temperature
20°C (68°F)
Chance of Rain
54%
Precipitation
143 mm (5.6 in)
Rainy days
16 days
Humidity
64% *
Sunshine
227 hours *
Percentage Sunshine
51% *
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Postojna typically rise from around 19°C (66°F) at the start of May to approximately 23°C (73°F) by the end. Nights are cool, with lows typically ranging from 9°C (48°F) to 12°C (54°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 for Postojna in May
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 May
Our historical data for Postojna spans 1976 to 2026, revealing these weather extremes.
- The warmest day in May was on May 26, 2009, with a maximum of 31°C (88°F).
- Postojna experienced its chilliest May day on May 6, 2021, reaching only 7°C (45°F).
- Postojna registered its coldest May night on May 7, 2019, with temperatures dropping to -1°C (30°F).
- Peak precipitation in May occurred on May 30, 2006, when 94 mm (3.7 in) of precipitation was measured.
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 →
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What to Wear in Postojna 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 Postojna in May
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.
