Click on a day for an hourly weather forecast
The temperatures in Rijeka in September are comfortable with low of 13°C and and high up to 21°C.
You can expect rain for roughly half of the month of September in Rijeka. 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 Rijeka in September 2025.
If you’re planning to visit Rijeka in the near future, we highly recommend that you review the 14 day weather forecast for Rijeka before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 5° / -2° | 10 | 16 | 4 | 195 mm | Awful | Rijeka in January |
| February | 7° / -1° | 10 | 14 | 4 | 220 mm | Awful | Rijeka in February |
| March | 10° / 2° | 8 | 21 | 2 | 172 mm | Awful | Rijeka in March |
| April | 15° / 7° | 8 | 22 | 0 | 143 mm | Ok | Rijeka in April |
| May | 19° / 10° | 12 | 19 | 0 | 217 mm | Ok | Rijeka in May |
| June | 23° / 14° | 11 | 19 | 0 | 188 mm | Good | Rijeka in June |
| July | 26° / 16° | 10 | 21 | 0 | 175 mm | Good | Rijeka in July |
| August | 26° / 16° | 6 | 25 | 0 | 136 mm | Perfect | Rijeka in August |
| September | 21° / 13° | 8 | 22 | 0 | 198 mm | Ok | Rijeka in September |
| October | 16° / 8° | 6 | 25 | 0 | 153 mm | Good | Rijeka in October |
| November | 11° / 5° | 10 | 20 | 0 | 242 mm | Bad | Rijeka in November |
| December | 7° / 0° | 9 | 19 | 2 | 210 mm | Awful | Rijeka in December |