High levels of birch pollen are spreading northward in Sweden over the coming days. At the same time the risk of oak pollen is rising in the southern parts of the country, according to the Swedish Museum of Natural History.
The Swedish Museum of Natural History warns of a birch pollen hit across large parts of northwestern Svealand, southern Norrland inland and along the Norrland coast. The risk is assessed as very high or elevated in these areas.
Birch flowering is now declining in southern Sweden. Instead oak pollen levels are rising in Skåne and Blekinge, where the risk is high. In the rest of Götaland and southern Svealand the risk remains elevated.
The measurements come from the museum’s pollen stations. The warning covers the coming days starting 9 May 2026.
