Normal weather for Koper in September
It's warm in September in Koper with an average temperature of 25°C. Temperatures this month range from a low of 22°C to a high of 28°C. At night, you can expect temperatures between 13°C and 18°C.
In September, there is an average of 115 mm of precipitation, spread over 15 days. The wind speed is around 3 Bft, mostly coming from the East.
Koper in September |
New York | ||
|---|---|---|---|
 Average Temperature |
25°C | 27°C | |
 High Temp |
28°C | 31°C | |
| Low Temp |
22°C | 21°C | |
 Total Precipitation |
115 mm | 57 mm | |
| Rainy Days |
15 days | 9 days | |
Start of September
The month of September starts in Koper with hot temps, averaging around 27°C during the day and nights around 17°C. A few showers might pop up early in the month, but overall, it’ll stay mostly sunny and dry.
With the temperature difference between day and night, it’s smart to wear layers. For the daytime, light clothing like shorts or a dress, and a hat and sunglasses are perfect. For the evening and morning, a shirt, maybe a light sweater, and thin pants are recommended.
Mid September
By mid-September, daytime temps stay steady at around 27°C, with nights around 17°C. During this part of the month, you might see regular precipitation, but there will also be some sunny days.
Since it cools down at night, it’s a good idea to wear layers. For the daytime, light clothing like shorts or a dress, and a hat and sunglasses are perfect. For the evening and morning, a shirt, maybe a light sweater, and thin pants are recommended.
End of September
By the end of September, the average daytime temperature in Koper is around 24°C, while nighttime temps are about 14°C. Expect regular precipitation, but if you’re lucky, you’ll also get some dry and sunny days.
Because temperatures drop in the evening, wearing layers is recommended. A T-shirt, light pants or skirt, and a light jacket are great for the day. In the evening and morning, choose a light jacket, sweater or hoodie, and long pants.
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UV index
The UV index is a maximum of 6 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Is September a good time to visit Koper?
Looking for sun? September isn’t a good month to be in Koper. The temperature is nice, but there’s too much chance of rain.
Temperature records for Koper in September
Check out the climate of Koper for all months and discover the best travel time
Curious about the weather in other parts of Slovenia? Check out the climate and weather for spots like Ljubljana, Bled, Bohinj, or explore other destinations in Slovenia.
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Daily Temperature in September in Koper
This chart shows the average daily high and low temperatures in September for Koper, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.
Daily Precipitation in September in Koper
The chart below shows the average daily precipitation in September for Koper, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect about 15 days of precipitation in Koper.
Daily UV Index in September in Koper
This chart shows the average daily UV index in September in Koper, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Koper Over the Years
This chart shows the average temperature in September in Koper, measured in degrees Celsius, over the past few years.
Total Precipitation in September in Koper Over the Years
This chart shows the average precipitation in September in Koper, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily Climate in September for Koper
Click on any day in September to get detailed info about the usual weather on that day in Koper. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Koper
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Average Weather in Koper by Month
Click on a month below to see detailed weather info for Koper. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
