Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 8.8 °C | 11.3 °C | 8 days | Unfavourable season |
| February | 10.3 °C | 10.2 °C | 9 days | Unfavourable season |
| March | 12.7 °C | 10.6 °C | 8 days | Possible, with trade-offs |
| April | 16.2 °C | 13.5 °C | 9 days | Possible, with trade-offs |
| May | 20.2 °C | 17.7 °C | 14 days | Possible, with trade-offs |
| June | 25.4 °C | 23.3 °C | 8 days | Ideal — one of the best times of year |
| July | 28.1 °C | 26 °C | 8 days | Ideal — one of the best times of year |
| August | 28.3 °C | 26.3 °C | 7 days | Ideal — one of the best times of year |
| September | 23.7 °C | 23.6 °C | 10 days | Pleasant — a good time to go |
| October | 19.1 °C | 19.8 °C | 10 days | Pleasant — a good time to go |
| November | 14.2 °C | 17 °C | 12 days | Possible, with trade-offs |
| December | 10.6 °C | 13.7 °C | 9 days | Unfavourable season |
Before you go
Three things to check once you have picked your dates.
Entry
Slovenia is in the European Union. Entry rules depend on your nationality — check before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 11 August 2026
Health
Recommended vaccinations, water quality, mosquitoes: advice depends on the country and the season. Some vaccines need time before departure.
Beau Fixe is not a safety or health authority. These notes summarise public advisories and link to their source; only the competent authorities are authoritative. Alert levels: Foreign, Commonwealth & Development Office (gov.uk), Open Government Licence v3.0.
FAQ
Can you swim in Piran in May?
The sea averages 17.7°C in May — too cold for most swimmers.
How hot is Piran in May?
Expect 20.2°C in the afternoon and 14.1°C at night, averaged over the last 10 years.
Does it rain a lot in Piran in May?
Around 14 days with rain (≥ 1 mm) in the month — 45% of days.