Weather in Koper: May
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Average day temperature: | 69.8°F |
| Average night temperature: | 54.1°F | |
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Sea water temperature: | 64.1°F |
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Number of sunny days: | 14 days |
| Day length: | 14.3 - 15.4 hours | |
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Number of rainy days: | 7 days |
| Precipitation totals: | 3.7 in. | |
| more information | ||
14 days
forecast
forecast
| Koper |
sea water
temperature
temperature
| Koper |
Air temperature in May, °F
Show year:
2025
2024
2023
The highest day temperature during May of 2025 was 73°F. At the same time the lowest night temperature was 51°F. Daily and nightly averages during May were 65.8°F and 57.8°F.
Sea water temperature in Koper in May, °F
Show year:
2025
2024
2023
The average sea water temperature in May of 2025 was 64.9°F. The highest and lowest sea temperatures during the month were 69.1°F and 60.3°F.
Sunny, partly cloudy and cloudy days
Number of sunny, partly cloudy and cloudy days in May is almost equal.
Precipitation total in May, in.
Precipitation total value in Koper in May is 4.2 in. Other months of the year show relatively similar values.
Wind speed in May, mph
The average wind speed value in May is 5.7 mph
Average sunny hours
This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in May is: 7.8.
Best time for vacation in Koper
Koper on a weather map
Places in Slovenia:
Name
°F
24 Hours Forecast
Koper
Local time: 05:43
December 05, friday
0600
43°F
W
4 mph
4 mph
0900
45°F
W
4 mph
4 mph
1200
50°F
SW
5 mph
5 mph
1500
48°F
SW
6 mph
6 mph
1800
45°F
SW
7 mph
7 mph
2100
39°F
SW
6 mph
6 mph
December 06, saturday
0000
39°F
SW
6 mph
6 mph
0300
43°F
SW
6 mph
6 mph
