Measurements:
°C
°F
CURRENT WEATHER
01:49
Koper
58°F
W 5 mph
Feels like: 58°F
Precip: 4%
World Resorts Slovenia Koper Weather

7 Day Weather Forecast

09.29
tue
DAY
78°F
S 2 mph
precip
1%
NIGHT
60°F
W 5 mph
precip
4%
09.30
wed
DAY
78°F
SW 2 mph
precip
1%
NIGHT
60°F
W 5 mph
precip
4%
10.01
thu
DAY
78°F
SW 2 mph
precip
1%
NIGHT
58°F
W 6 mph
precip
8%
10.02
fri
DAY
76°F
SW 8 mph
precip
9%
NIGHT
60°F
W 6 mph
precip
3%
10.03
sat
DAY
74°F
SW 11 mph
precip
6%
NIGHT
56°F
W 6 mph
precip
3%
10.04
sun
DAY
72°F
NW 5 mph
precip
1%
NIGHT
56°F
W 4 mph
precip
11%
10.05
mon
DAY
72°F
NW 2 mph
precip
5%
NIGHT
56°F
W 6 mph
precip
12%

Koper Sea Water Temperature in September, °F

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Koper was 25.2°F. The maximum and minimum values were 22.9°F and 27.5°F respectively.

Koper on the Weather Map

Best Time to Visit Koper
The most sunny months:
August 23 days
July 22 days
June 20 days
The most warm months:
August 89.2 °F
July 88.7 °F
June 83.7 °F
Warmest sea temperature:
August 81.7 °F
July 81.3 °F
September 76.7 °F
The most cold months:
January 45.0 °F
December 47.8 °F
February 48.1 °F
The most rainy months:
May 7 days
November 6 days
September 6 days
The most windy months:
March 6 mph
February 6 mph
November 6 mph
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