The temperatures in Istria in September are comfortable with low of 19°C and and high up to 23°C.
You can expect about 3 to 8 days of rain in Istria during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Istria in September 2025.
If you’re planning to visit Istria in the near future, we highly recommend that you review the 14 day weather forecast for Istria before you arrive.
Temperatures
23° / 19°
Rainy Days
7
Snowy Days
0
Dry Days
23
Rainfall
239
mm
Sun Hours
11.3
Hrs
