On Friday, the first snow fell in the Western Balkans for this season and many people were left without electricity.
Snow has blanketed mountains in Serbia and Bosnia, bringing down power lines and trees.
Meteorologists in Serbia issued a warning for severe weather in the central and southern parts of the country, AP reports.
According to them, more than half a meter of snow could fall in mountainous areas, which could be a record for the month of October.
The municipality of Ivanjica, in central Serbia, declared a state of emergency to deal with the problems caused by the snow.
The southwestern municipalities of Medveđa and Crna Trava were left without drinking water and no telephone network, according to officials there.
Not long ago, temperatures in the Western Balkans reached 30 degrees Celsius, but then the weather suddenly cooled.
Experts say these strong weather changes, such as unseasonal heat or cold, may be linked to climate change.