Click on a day for an hourly weather forecast
The temperatures in Postojna in September are comfortable with low of 10°C and and high up to 21°C.
You can expect rain for roughly half of the month of September in Postojna. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Postojna in September 2025.
If you’re planning to visit Postojna in the near future, we highly recommend that you review the 14 day weather forecast for Postojna before you arrive.
Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
---|---|---|---|---|---|---|---|
January | 4° / -2° | 10 | 8 | 14 | 167 mm | Awful | Postojna in January |
February | 5° / -2° | 10 | 7 | 13 | 208 mm | Awful | Postojna in February |
March | 9° / 1° | 8 | 16 | 6 | 170 mm | Awful | Postojna in March |
April | 14° / 4° | 8 | 20 | 3 | 153 mm | Bad | Postojna in April |
May | 18° / 7° | 13 | 18 | 0 | 231 mm | Ok | Postojna in May |
June | 24° / 11° | 11 | 19 | 0 | 219 mm | Good | Postojna in June |
July | 26° / 13° | 10 | 21 | 0 | 201 mm | Good | Postojna in July |
August | 26° / 13° | 8 | 23 | 0 | 173 mm | Good | Postojna in August |
September | 21° / 10° | 9 | 21 | 0 | 233 mm | Ok | Postojna in September |
October | 15° / 6° | 7 | 23 | 1 | 182 mm | Ok | Postojna in October |
November | 10° / 3° | 11 | 16 | 3 | 259 mm | Awful | Postojna in November |
December | 5° / -1° | 8 | 13 | 10 | 213 mm | Awful | Postojna in December |