In southern Finland, pollen from alder has been carried over from farther southern Europe during the weekend. More pollen from alder and hazel is expected to reach the southern and central regions of Finland in the upcoming days. According to a statement from the University of Turku, the amount of pollen arriving in Finland is currently very low, as the spring season in Central Europe is much more advanced than in Finland; for instance, Denmark is already experiencing high concentrations of alder and hazel pollen in the air. In Finland, flowering is anticipated to commence in the southern and southwestern parts of the country in about two weeks, where alder is found almost nationwide and hazel primarily in the southern and southwestern regions.

Both types of pollen are allergens, and cross-allergy with birch pollen is common, affecting about one-fifth of the population. Furthermore, the delayed onset of flowering this year has been attributed to a cold spell. With the increasing prevalence of pollen from southern Europe, the University of Turku has started regular pollen reports on Mondays to inform the public about current pollen situations and forecasts.