Situation and medium-term forecast for

Issued 14th of January 2020

Situation and medium-term forecast

Locally the hazel has started to flower!

In climatically favoured locations (southern exposure, lowland habitats) all over Austria more and more catkins of hazel are reaching readiness to flower. In the west of Austria the mild weather conditions have been forecasted until Friday, which may lead to local low to middle allergenic burden. For the weekend the worsening of weather conditions (temperatures below 5° C, rain, snow) will lead to a decrease of allergenic burden.

The Spaeht’s alder has ceased to flower (peak flowering was reached during the Christmas holidays). This tree is not native to Austria and only found cultivated (e.g. park tree), therefore its remaining allergenic burden is heavily restricted to the sites of individual specimens. The catkins of native alder trees (black alder) are not yet well developed.

According to our forecasting models the readiness to flower of black alder will be reached in the next few days. Based on observations on reference trees the actual starting day of flowering is not expected to happen until the end of January.


We expect the readiness to flower for hazel inon
St. Pölten15.01.2020
Salzburgready to flower
Grazready to flower
Munichready to flower

Forecast from 14.01.2020
Note: The model results give an indication of the expected start of flowering, based on information provided by local pollen warning services with direct reference to the local situation. Start of flowering is not to be equated with the beginning of the pollen season. When the start of flowering is achieved, the majority of the plants have the potential to release pollen, but only when weather conditions are favourable.

Responsible for the content: and the Department of Oto-Rhino-Laryngology of the Medical University Vienna, Research group aerobiology and pollen information
Uwe E. Berger MBA, Mag. Maximilian Bastl PhD and Mag. Dr. Katharina Bastl
medium-term forecast based on model and pollen data from Austria and surrounding countries
reprint and publication in parts or completely is permitted only quoting the source

weather data and today´s forecasts based synoptic data: ZAMG (Zentralanstalt für Meteorologie und Geodynamik)
zum Team

to the top