The night before Sunday offered minus degrees in almost the whole country.
The coldest was in the village of Naimakka, where SMHI's weather station measured the temperature to minus 5.9 degrees.
Cooler air has drawn in over Sweden from the north, but in the coming days, milder air masses will take over again.
- September is a season that can vary quite a lot, the beginning of the month can have elements of late summer, while the end rather has a flurry of winter, says Linus Karlsson, meteorologist at SMHI to TT.
According to SMHI's seasonal definitions, meteorological autumn already prevails in the interior of Norrland.
Large parts of the rest of Norrland and Sveland have autumn temperatures.