Temperature in Slovenia is increasing faster than global average. Increase in the annual average temperature is most evident in the last three decades. Warming of the atmosphere will continue according to the climate change projections. The result of warming is an increase in sea level (due to melting of glaciers and thermal expansion), increase in level of the greenhouse gases in the atmosphere (contributes to warming), and many extreme weather and climate events (like floods, droughts, hail and heavy wind), which will influence the quality of our lives.

Temperature observations show increasing trend of maximum and minimum absolute temperature in between 1961 and 2022, reflecting a global warming. Number of hot days is increasing, including the frequency of extreme hot days with daily maximum temperature above 35 °C. In the summer of 2013, the highest temperature so far was measured in Slovenia, and local temperature records were observed at many meteorological stations. A record number of hot days was observed in 2022. Number of days with temperature below zero show a decline.

Asthma is the most common chronic disease among children and one of the major causes of hospitalization to the age of fifteen. In 2019, in EU countries, the share of people reporting asthma was 5,7 %, and for Slovenia it was 4,8 %.  In the period 2017-2021, the municipalities of Kostel, Kobilje and Cankova stood out in terms of the number of hospitalizations for asthma. Recent evidences support relationship between exposure to air pollution and exacerbation of asthma, mainly due to exposure to particulate matter (PM₁₀).

Comparison of periods 1961-1990 and 1991-2020 on the chosen representative stations around Slovenia shows decrease of heating degree days by around 10 % and multiple increase of cooling degree days. With projected continuous temperature raise until the end of 21st century, those trends are expected to continue. Thus, in Slovenia, energy demand for cooling will increase in the warmer period of the year, while the energy demand for heating will decrease in colder period of the year. Same trend is projected for Europe in general.

Annual growing season length is increasing almost everywhere in Europe, mostly in Eastern and Northern part. In Slovenia, the length of the annual growing season is increasing, especially since mid-1990s. According to projections, the duration of the annual growing season throughout Europe will increase in future.