This weekend, the Czech Republic experienced a final breath of summer as temperatures soared above 30°C (86°F). Such tropical temperatures are highly unusual this late in the season, marking one of the latest tropical days in the country’s measurement history. Weather forecasts indicate this heat wave is ending, with temperatures expected to drop below 20°C (68°F) in the coming days, ushering in true autumn weather.
In Dobřany near Plzeň, Sunday saw temperatures reach 30.4°C (86.7°F). Record-breaking heat was recorded at 30% of stations that have been measuring for more than 30 years, with six stations registering tropical temperatures. According to climate data, September 21st rarely sees temperatures exceeding 30°C, making this an exceptionally late tropical day.
Climate scientist Pavel Zahradníček has compiled data from 186 stations with regular measurements since 1961, revealing a gradual shift of tropical days toward later dates in the year. The latest tropical temperature in the Czech Republic since 1961 was recorded on September 23, 2003. Zahradníček notes that climate change is not only increasing the frequency of tropical days but also extending their seasonal range – from previously occurring mainly in July and August to now appearing as early as May.
The impact of climate change is evident in the increasing number of days with tropical temperatures in the Czech Republic. For instance, “super-tropical days” (temperatures above 35°C/95°F) are now ten times more frequent than in the 1960s-1990s. Similarly, tropical nights—when temperatures don’t drop below 20°C (68°F)—have increased fifteenfold in Prague compared to previous decades.
This phenomenon isn’t limited to the Czech Republic. Recently, northern Norway recorded its latest tropical night in measurement history, further indicating shifting global climate patterns. While climate scientists predict tropical days may occur slightly later in the future, the most significant change will be in their overall frequency rather than seasonal timing.