When the temperature does not drop below 20 degrees at any point during the night, it is called a tropical night.
Malmö has had a tropical night. There may have been tropical nights at more places in Sweden, but right now we only have access to certain stations, says Andersson.
The phenomenon is unusual in Sweden in September, but it is not the first time that southern Sweden experiences tropical nights this late in the year.
Firstly, there must be warm air and often clouds are required so that there is no radiation of heat.
Last week, a 49-year-old heat record was broken when the temperature rose to 31.1 degrees in Helsingborg and Lund. More local heat records were also broken, but now a cooler week is expected throughout Sweden.
Tomorrow, we don't see any giant temperatures. It will be around 15 degrees at most in southern Sweden. So it will be significantly cooler, says Andersson.
But it's too early to say that all of Sweden is leaving summer and entering autumn.
The daily temperature should be lower than 10 degrees for five days. It doesn't look like autumn in southern Sweden. But it varies in Sweden. Locally in the Jämtland Mountains and large parts of the Lapland Mountains, it has been autumn since September 1st.