In Norway, meteorologists define a 'summer day' as any day in which temperatures top 20C. That mark was passed in at least ten counties on Sunday.
The 25.4C official reading at Stavanger Airport, Sola marked the highest recorded temperature in years. To see temperatures this high this early in the year, one has to go back to the 25.2C recorded on April 30th, 1993.
The highest temperature measured in Norway on Sunday was in Stavanger's Våland district, where the mercury topped out at 26.2C.
What everyone wants to know, of course, is how long this unseasonably warm weather will last. There, the Norwegian Meteorological Institute has some good news – at least for now.
“It can be just as warm or maybe even a little warmer on Monday but then it's going to turn,” meteorologist Dag Kvamme told broadcaster NRK.
Kvamme said that a low pressure system will move in from the north after Monday bringing significantly colder air and highs of around 10-11C throughout southern Norway.
Looking ahead to the Whit Monday national holiday on May 16th and Norway's National Day on May 17th, Kvamme had some bad news.
“There will be serviceable weather through Thursday but the prospects for Pentecost and May 17th don't look so promising,” he told NRK.
There was, however, a silver – or perhaps we should say a yellow – lining, as the clear skies are expected to remain as the temperatures drop.
“Thus far, there is little or no precipitation in the forecast,” Kvamm said.