Hazel and alder (alnus) is flowering in Southern Norway, but the key allergen to many of us is birch. When can we expect the birch pollen season to start?
Last year, it was already here
In 2020, the birch pollen season started in early April in Southern Norway, a fairly typical onset. Northern Norway was covered by snow unusually late in Spring, and didn’t see levels peak before June. To watch the development of pollen in a typical year, take a look at our video.
This year, we expect another two weeks before the season kicks in
The birch pollen spread has started in Europe, reaching Denmark and the southern tip of Sweden. No birch pollen has yet been measured in Norway.
Birch starts flowering in Southern and Central Europe, then the pollen front gradually moves to the north. When pollen levels in England, Germany and Poland are high, it typically takes 1-2 weeks before the flowering starts in Norway (and the parts of Sweden on the same latitude).
As we can see from today’s birch pollen map, we’ve still got a way to go before we reach high levels on the continent.
Colder than usual in Europe
Weather, and notably temperature, determines when the pollen season starts. The temperature map tells us that the next week is forecasted to be colder than normal for most of Europe, including Norway. (With the exception of the arctic island group of Svalbard.)
Our best estimate is that it will take approximately another two weeks before the birch pollen season kicks off in Norway. Of course, a rise in temperature could very well move the onset earlier (and colder temperatures delay it even more).
Get your pollen forecasts in the Airmine app
A 4-day pollen forecast is now available for European locations in our Airmine app, together with pollen maps.
We are continuously working on our pollen models and will improve them over the next months. Any feedback from our readers/users regarding on how to improve the forecasting service is much appreciated!
Download the Airmine app here: