Forecast

Heatwave, falling grass pollen levels and mugwort flowering is gathering pace!

As the main flowering season for grasses is already over and mugwort is only just beginning to flower, a moderate pollen count is expected over the coming days. For the second half of the week, the weather forecast predicts another heatwave with temperatures between 35 °C and 40 °C. On Saturday afternoon, the likelihood of thunderstorms will increase. This is relevant for people with pollen allergies, as pollen can burst open before thunderstorms with increased lightning activity. This can release large quantities of the allergen into the air and lead to very sudden spikes in pollen levels, known as ‘thunderstorm asthma’. The warm, humid conditions following the thunderstorms will result in increased fungal spore counts.

The peak of grass pollen season has now passed in the Weinviertel, the Danube region and the Vienna Basin. Low or moderate pollen levels are generally expected in these areas. However, in forests or along streams, there may still be locally intense pollen dispersal. As long as the sun is shining, symptom-triggering grass pollen dispersal may occur in the southern mountainous regions of Lower Austria. If the wind is blowing in the right direction, grass pollen can be carried from there into the lowlands, increasing local pollen levels. This is particularly likely in the afternoon and evening. 

People who are sensitive to grass pollen should avoid flowering maize fields. Maize pollen is among the largest in the plant kingdom and therefore only travels short distances. As a result, high pollen counts only occur in the immediate vicinity of maize fields.

In meadows, stinging nettles, sorrel and plantain continue to flower and contribute to pollen levels.

The flowering of common mugwort is gathering pace. The peak flowering period is expected in the first half of August. Dense stands, such as those found on railway embankments, rubbish tips, roadsides and along streams and rivers, should be avoided by people with sensitisation. For this group of allergy sufferers, cross-reactions to celery, carrots and camomile may occur.

Ragweed is also growing and sprouting; it will take until well into August before it flowers. If you spot ragweed populations whilst out and about, please feel free to report them via the ‘Ragweed Finder’ citizen science platform. Reports can be submitted either via the website ragweedfinder.at or via the app (for Android and iOS). The reports are checked by experts from the “Ragweed Finder” team, plotted on the ragweed map and forwarded at regular intervals to the relevant authorities in the federal states. These authorities can then use the sightings to take further action.

Over the coming days, moderate to high levels of fungal spores are expected across the country. Fungi release more spores following rainfall. Relief can be found by spending time at higher altitudes, as the concentration of fungal spores decreases significantly with increasing altitude.

In addition to the pollen types already mentioned, the pollen spectrum currently also includes pollen from bee balm, umbellifers, hops, hemp, amaranths, papilionaceous plants and juniper. However, these pose only a low allergenic risk.