When the temperature does not drop below 20 degrees at any point during the night, it is called a tropical night.
The large island and Rödkallen on the Norrbotten coast had a tropical night towards July 14, and thereafter Rödkallen had another one. Bjuröklubb in Skellefteå municipality has also shown a nocturnal temperature of over 20 degrees. Further south, the nights have also offered warmth. The night towards July 18 and July 19, the west coast Väderöarna and Måseskär had tropical nights.
Tropical nights are rarer inland and have not been registered. But the Kettstaka measuring station at Vättern in southernmost Närke was closest – with 19.4 degrees as the lowest on the night towards July 19.
The night towards Monday has conditions for new tropical nights in some parts of the country.
Norrbotten coast and West Coast towards Bohuslän seem to have the greatest opportunity for it, says Westberg.
Then a cold front comes in from the southwest. But in the north, the heat remains for a while.
It may possibly become another tropical night a little later in the week.
