If you're looking for summer vibes, the best time to travel to Portoroz is in July, August and June, when the average temperature reaches 22.58 °C, while August, July and June are the 3 sunniest months of the year, with an average of 149.92 hours.
However, if you prefer colder temperatures, make sure you visit Portoroz during January, February or December to experience an average of 4.07 °C.
For those who don't care too much about temperatures, but want to avoid getting wet in the rain, it's important to avoid travelling during January, December and February, when the average precipitation in Portoroz is 10.5 mm, while the months of January, February and March are drier, with an average of 0 mm.