Koper in september: average Weather, Temperature and Climate
Weather in Koper in september 2025
The weather in Koper in the month of september comes from statistical datas on the past years. You can view the weather statistics for all the month, but also navigating through the tabs for the beginning, the middle and the end of the month.
Average weather throughout september
good weather UV index: 6
Weather at 6am
63°F
Clear/Sunny
48% of time
24%
13%
12%
Weather at 12pm
76°F
Clear/Sunny
44% of time
22%
19%
14%
Weather at 6pm
67°F
Clear/Sunny
48% of time
19%
19%
14%
Weather at 3am
63°F
49%
22%
19%
9%
Evolution of daily average temperature and precipitation in Koper in september
These charts show the evolution of average minimum/maximum temperatures as well as average daily precipitation volume in Koper in september.
The climate of Koper in september is good
The weather in september in Koper is wet (with 9.4in of rainfall over 9 days). The weather's not getting better compared to the previous month since in august there is an average of 5.9in of precipitation over 7 days.
The climate nice there this month. The high seasonal norm is 76°F. The minimum is 63°F. Thus, the mean temperature average in september in Koper is 70°F. These temperatures are far removed from those records observed in Koper in september with a maximum record of 92°F in 2021 and a minimum record of 49°F in 2017.
On this month of september, day length in Koper is generally 12:32. The sun rises at 05:44 and sunset is at 18:16.
With a good weather, this month is a good time to go there in Slovenia.
Seasonal average climate and temperature of Koper in september
Check below seasonal norms These datas are set from the weather statements of the past years of september.
| September | |||||
| Outside temperature | |||||
| Average temperature | 70°F | ||||
| Highest temperature | 76°F | ||||
| Lowest temperature | 63°F | ||||
| Highest record temperature | 92°F (2021) | ||||
| Lowest record temperature | 49°F (2017) | ||||
| Number of days at +86°F | 2 day(s) (7%) | ||||
| Number of days at +65°F | 29 day(s) (97%) | ||||
| Sea temperature | |||||
| Average sea temperature | 74°F | ||||
| Lowest sea temperature | 69°F | ||||
| Highest sea temperature | 80°F | ||||
| Wind | |||||
| Wind speed | 14km/h | ||||
| Wind temperature | 63°F | ||||
| Precipitation (rainfall) | |||||
| Rainfall | 9.4in | ||||
| Number of days with rainfall | 9 day(s) (31%) | ||||
| Record daily rainfall | 4.8in (2010) | ||||
| Other climate data | |||||
| Humidity | 79% | ||||
| Visibility | 9.37km | ||||
| Cloud cover | 27% | ||||
| UV index | 6 | ||||
| Daily sunshine hours | 12 | ||||
| Sunrise and sunset | |||||
| Time of sunrise | 05:44 | ||||
| Time of sunset | 18:16 | ||||
| Length of day | 12:32 | ||||
| Our opinion about the weather in september | |||||
| Our opinion at whereandwhen.net | good | ||||
How was the weather last september?
Here is the day by day recorded weather in Koper in september 2024:
76°F to 86°F
76°F to 86°F
74°F to 81°F
72°F to 83°F
72°F to 85°F
68°F to 76°F
70°F to 79°F
72°F to 79°F
72°F to 76°F
65°F to 76°F
68°F to 76°F
70°F to 72°F
58°F to 61°F
59°F to 65°F
61°F to 67°F
59°F to 68°F
58°F to 65°F
58°F to 70°F
67°F to 74°F
63°F to 74°F
63°F to 72°F
61°F to 72°F
63°F to 72°F
67°F to 68°F
65°F to 68°F
67°F to 70°F
68°F to 72°F
67°F to 70°F
58°F to 67°F
52°F to 65°F
Map: other cities in Slovenia in september
Cities near Koper:
| Ankaran in september | good weather |
| Izola in september | good weather |
| Kostabona in september | good weather |
| Portorož in september | good weather |
| Piran in september | good weather |
| Sežana in september | good weather |
| Stanjel in september | good weather |
| Predjama in september | good weather |
| Ilirska Bistrica in september | good weather |
| Postojna in september | good weather |
| Nova Gorica in september | good weather |
| Idrija in september | good weather |
Click over cities on the map for information about the weather in september.
Koper
perfect weather
good
tolerable
bad
very bad
Weather data for Koper in september:
Weather data for Koper for september are derived from an average of the weather forecast since 2009 in Koper. There is a margin of error and these forecasts are to be considered as general information only. The weather in Koper can vary slightly from year to year, but this data should limit surprises. So you can pack your bags or check for the best time in year to go to Koper.