Unusually warm air is spreading from France through Germany and Italy to the Balkans. In the Serbian capital, Belgrade, temperatures are set to reach as high as 25°C by the end of the week.

The normal temperature there at this time of year would be closer to 15°C.

Behind these unusual temperatures lies a powerful low-pressure system that is pushing warm air northwards from North Africa. At the same time, it is bringing heavy rain and storms to the Iberian Peninsula.

Further north, the weather picture is quite different: another low-pressure system is bringing freezing polar air to the region. It is snowing in Oslo, and even in Berlin temperatures are mostly barely rising above 5°C.

The boundary between warm and cold air runs roughly across Central Europe. From this weekend, the colder air will also reach the south along with frosty conditions for the UK and Ireland.