The climate in Slovenia

Average daytime and nighttime temperatures

All climatic diagrams of this page are taken from the collected data from 84 measuring stations in Slovenia.
Weather stations at an altitude above 2520m have not been included.
All data correspond to the average monthly values of the last 20 years.

Back to overview: Slovenia

Climate zone: Moderate zone of the northern hemisphere

The climate in Slovenia is much more unsettled than in central Europe and offers varied seasons with deep winters and warm summers. It rarely gets really warm here and you can safely leave your swimwear at home. Due to the warmer temperatures the best time for traveling is from May to September. Winter athletes will find their favorite weather conditions from December to January.

Duration of daylight and sunshine in Slovenia

hours of sunshine per daySunshine hours per day in Slovenia
rainy days per monthRainy days per month in Slovenia
Precipitation in mm/dayPrecipitation in Slovenia
Water temperatureWater temperatures in Slovenia
Relative humidity in %Relative humidity in Slovenia
Absolute humidity in g/m³ (approx.)Absolute humidity in Slovenia

Temperature records of the last 46 years

The hottest temperature measured from 1975 to June 2021 was reported by the Ljubljana Bezigrad weather station. In August 2013 the record temperature of 40.2 °C was reported here. The hottest summer from July to September, based on all 2 weather stations in Slovenia below 2520 metres altitude, was recorded in 2011 with an average temperature of 21.1 °C. This average temperature will normally be measured every 4 to 6 hours, thus also including the nights. Normally, this value is 19.4 degrees Celsius. The average maximum daily temperature at that time was 27.5 °C.

The coldest day in these 46 years was reported by the weather station Ljubljana Bezigrad. Here the temperature dropped to -16.2 °C in January 2003. Ljubljana Bezigrad lies at an altitude of 298 meters above sea level. The coldest winter (January to March) was in 1985 with an average temperature of -1.1 °C. In Slovenia, it is usual to have about 4.2 degrees more at 3.2 °C for this three-month period.

Long-term development of temperatures from 1991 - 2020

In contrast to single record values, a long-term development cannot simply be brought about by all weather stations in the country. Both the number and the locations are constantly changing. A simply calculated average value would give a falsified result. If several measuring stations in particularly cold mountain or coastal regions are added in one year, the average would already decrease as a result of this alone. If a station fails during the summer or winter months, it does not provide any values and falsifies the average again. The subsequent long-term development was therefore reduced to only 1 measuring points in order to have actually comparable data over as long a period as possible.

In the years 1991 to 2020 there were only these 1 weather stations in the whole country, which reported continuous temperature values (Ljubljana Bezigrad). From these weather reports we have created a long-term development that shows the monthly average temperatures. The hottest month in this entire period was 2015 with 24.4 °C. 2017 was the coldest month with an average temperature of -3.2 °C.

The average annual temperature was about 10.8 °C in the years after 1991 and about 12.1 °C in the last years before 2020. So in less than 30 years it has increased by about 1.3 °C. This trend only applies to the selected 1 weather stations in Slovenia. A considerably more comprehensive evaluation of the global warming has been provided separately.

Long-term development of temperatures in Slovenia

More detailed information on global warming with a view by continent can also be found on our topic page on climate change. Data basis: German Weather Service, individual values averaged and supplemented by own elements.