Climate averages 1991–2020
Banja Luka 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 Banja Luka: daytime highs average 22.2°C and nights cool to about 12.0°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 95 mm of rain on roughly 11 days, which makes September a wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 34 min on an average September day.
The nearest other city in this atlas is Zenica (85 km away). In September its highs average 21.9°C, about as warm as Banja Luka, with 94 mm of rain.
Among the 7 cities listed in Bosnia and Herzegovina, Banja Luka ranks 2nd of 7 for the warmest September highs and 5th of 7 for the driest September (rainfall, lowest first). The mean September high of those 7 cities is 22.0°C; Banja Luka is 0.2°C warmer than that mean.
From September to October, average highs fall by 4.8°C to 17.4°C, and monthly rainfall falls from 95 mm to 72 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
Banja Luka climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 5.3°C-2.8°C | -2.8°C | 70 | 10.4 | 9.29 h |
| February | 7.4°C-2.1°C | -2.1°C | 70 | 10.4 | 10.410 h |
| March | 12.3°C1.3°C | 1.3°C | 79 | 11.5 | 11.912 h |
| April | 17.1°C5.5°C | 5.5°C | 92 | 12.7 | 13.513 h |
| May | 21.3°C10.1°C | 10.1°C | 112 | 13.5 | 14.815 h |
| June | 25.0°C14.2°C | 14.2°C | 97 | 11.9 | 15.516 h |
| July | 27.4°C16.3°C | 16.3°C | 87 | 10.4 | 15.215 h |
| August | 27.5°C16.3°C | 16.3°C | 72 | 8.8 | 14.114 h |
| September, selected | 22.2°C12.0°C | 12.0°C | 95 | 10.9 | 12.613 h |
| October | 17.4°C7.7°C | 7.7°C | 72 | 9.2 | 11.011 h |
| November | 11.5°C3.2°C | 3.2°C | 85 | 10.2 | 9.610 h |
| December | 6.0°C-1.3°C | -1.3°C | 82 | 11.5 | 8.99 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
- Zenica in SeptemberBosnia and Herzegovina · 85 kmHigh 21.9°C · Low 12.5°C · 94 mm rain
- Bihać in SeptemberBosnia and Herzegovina · 105 kmHigh 21.6°C · Low 12.4°C · 124 mm rain
- Tuzla in SeptemberBosnia and Herzegovina · 119 kmHigh 22.1°C · Low 12.3°C · 86 mm rain
- Ilidža in SeptemberBosnia and Herzegovina · 137 kmHigh 21.1°C · Low 12.0°C · 91 mm rain
- Sarajevo in SeptemberBosnia and Herzegovina · 138 kmHigh 21.1°C · Low 11.7°C · 91 mm rain
- Osijek in SeptemberCroatia · 145 kmHigh 22.7°C · Low 13.4°C · 59 mm rain
- Zagreb in SeptemberCroatia · 150 kmHigh 21.8°C · Low 12.6°C · 94 mm rain
- Split in SeptemberCroatia · 154 kmHigh 24.2°C · Low 16.6°C · 103 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 Banja Luka) is explained once on the Banja Luka year overview and on the Sources, method and limits page.