Koper weather in August
Temperature, sea and sunshine in August: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in August
Excellent
Best time to visit: June – August
What is the weather like in Koper in August?
In August, Koper is warm: daytime highs average 27 °C, and even at night it stays warm at around 21 °C. The sea averages 25.5 °C – pleasant for swimming. With around 9 hours of sunshine a day, there is plenty of sun. Rain falls on about 9 days, adding up to 90 mm. The air is often humid and muggy. All in all, August is an excellent month for a holiday in Koper.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 94 | 93 | 66 |
| Day | 27° | 27° | 22° |
| Night | 21° | 21° | 17° |
| Sea | 25° | 26° | 23° |
| Sun | 10 h | 9 h | 7 h |
| Rain days | 8 | 9 | 10 |
More details for August
- Daylight
- 14 h 11 min06:05 – 20:15
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 17 daysdew point 18 °C or moreAll months
- Wind
- 14 km/haverage daily peakAll months
- Cloud cover
- 39 %on averageAll months
- Hot days
- 4 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snow
- Time zone
- UTC+2Europe/Ljubljana
How the score comes together
- Temperatureweight 35 %100 %
- Seaweight 25 %100 %
- Sunshineweight 20 %100 %
- Few rainy daysweight 20 %67 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in August
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Insect repellent
- Rain jacket or umbrella
Koper in August: quick answers
Is Koper hot in August?
Warm rather than hot: in August, daytime highs in Koper average 27 °C and nights cool to about 21 °C. On about 4 days the thermometer climbs to 30 °C or more.
Can you swim in Koper in August?
Yes. In August the sea averages 25.5 °C – pleasant for swimming.
Does it rain much in Koper in August?
Rain falls on about 9 days, adding up to 90 mm.
Koper month by month
The whole year in KoperAll destinations: SloveniaWhere to go in AugustSea temperature in August
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences