"It will be sunny in most parts of the country, but in Värmland, Dalarna and Norrland there may be clouds and even rain," said Sandra Andersson at weather agency SMHI.
Temperatures stand to soar to around 20 degrees Celsius during the day, cloud permitting.
"It may be a bit cooler where it is cloudy," Andersson cautioned.
The fine weather is set to continue into the evening and Friday with pleasant temperatures across much of Sweden.
Swedish National Day festivities have gradually become more organized since the day became an official public holiday in 2005.
However, Swedes are still finding their way when it comes to celebrating National Day, which still lacks the festive, almost carnival-like atmosphere that characterizes how Norwegians, for example, mark their May 17th National Day.
The day still retains some of its political associations, with Swedish nationalists on the one side, and anti-fascists on the other and according to some experts this may have an effect on how the day is celebrated.
The day has become an important event for new Swedes however with many municipalities organizing citizenship ceremonies on June 6th to welcome those who have recently become Swedish citizens.
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