Climate averages 1991–2020
Rijeka weather
in September.
A warm, wet month: the 4th warmest and the 10th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Rijeka: daytime highs average 22.3°C and nights cool to about 14.8°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 177 mm of rain on roughly 12 days, which makes September a wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 35 min on an average September day.
The nearest other city in this atlas is Trieste (63 km away). In September its highs average 22.3°C, about as warm as Rijeka, with 170 mm of rain.
Among the 4 cities listed in Croatia, Rijeka ranks 3rd of 4 for the warmest September highs and 4th of 4 for the driest September (rainfall, lowest first). The mean September high of those 4 cities is 22.7°C; Rijeka is 0.5°C cooler than that mean.
From September to October, average highs fall by 5.0°C to 17.3°C, and monthly rainfall rises from 177 mm to 208 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Rijeka climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 6.8°C0.7°C | 0.7°C | 122 | 11.5 | 9.29 h |
| February | 8.1°C0.9°C | 0.9°C | 128 | 10.8 | 10.410 h |
| March | 12.1°C4.0°C | 4.0°C | 123 | 11.6 | 11.912 h |
| April | 16.5°C8.1°C | 8.1°C | 114 | 13.0 | 13.513 h |
| May | 20.7°C12.6°C | 12.6°C | 120 | 13.7 | 14.915 h |
| June | 24.9°C16.7°C | 16.7°C | 94 | 12.0 | 15.616 h |
| July | 27.6°C18.9°C | 18.9°C | 77 | 10.0 | 15.315 h |
| August | 27.9°C19.0°C | 19.0°C | 90 | 8.7 | 14.114 h |
| September, selected | 22.3°C14.8°C | 14.8°C | 177 | 11.8 | 12.613 h |
| October | 17.3°C10.7°C | 10.7°C | 208 | 13.4 | 11.011 h |
| November | 12.2°C6.5°C | 6.5°C | 223 | 14.4 | 9.610 h |
| December | 7.7°C2.0°C | 2.0°C | 169 | 12.2 | 8.89 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Trieste in SeptemberItaly · 63 kmHigh 22.3°C · Low 14.8°C · 170 mm rain
- Ljubljana in SeptemberSlovenia · 81 kmHigh 19.8°C · Low 11.5°C · 125 mm rain
- Udine in SeptemberItaly · 125 kmHigh 21.4°C · Low 12.3°C · 153 mm rain
- Bihać in SeptemberBosnia and Herzegovina · 126 kmHigh 21.6°C · Low 12.4°C · 124 mm rain
- Zagreb in SeptemberCroatia · 131 kmHigh 21.8°C · Low 12.6°C · 94 mm rain
- Klagenfurt am Wörthersee in SeptemberAustria · 145 kmHigh 19.2°C · Low 11.1°C · 139 mm rain
- Maribor in SeptemberSlovenia · 165 kmHigh 20.5°C · Low 11.9°C · 111 mm rain
- Mestre in SeptemberItaly · 172 kmHigh 23.0°C · Low 15.5°C · 123 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Rijeka) is explained once on the Rijeka year overview and on the Sources, method and limits page.