This Friday, September 23, is the first day of autumn, and the equinox, a time of year when the length of day and night are equivalent. From this date, the nights will progressively increase in length to the detriment of the days. For this first weekend of fall, we will find a cool, disturbed and stormy weather pattern across much of the country bringing the last of the pollen to the ground and heralding the end of the 2022 pollen season.
As confirmed by the RNSA (www.pollens.fr), the risk of allergy will no longer exceed the average level in the departments most infested with ragweed such as Nièvre, Ain, Rhône, Ardèche, Isère, Vaucluse, Gard. It is almost the end of the ragweed bloom and allergy sufferers will be able to breathe easier as soon as the last pollens have been released into the air. The risk of allergy will be low in other places less affected by ragweed pollen.
Credit: The Weather Channel
Cedars are currently the last trees to flower and pollination is just beginning with the first pollens visible on our sensors. Cedars will release large amounts of pollen into the air in late September or early October. This is because the structure of the cedar pollen grain is made up of two side balloons that fill with air, helping it to be easily carried by the wind. They can drift for several kilometers and stay in the air for a long time. Cedar pollen usually covers exterior surfaces (balconies, cars, sidewalks, windows, roads, etc.) with a yellow powder, but without bothering allergy sufferers, since its allergenic potential is very low. However, in the presence of very large quantities, especially near the tree, sensitive individuals may experience discomfort. Therefore, it is advisable to consult a doctor in case of serious discomfort.
It is also the end of the flowering of grasses, urticaceae (nettles), artemisias and bananas. The allergy risk can locally reach the low level for the last grass pollen present in the air!
Allergy sufferers will finally be able to rest easy for a few months before the return of pollen from cupresaceae-taxaceae at the end of November in the Mediterranean, and from hazelnuts and alders at the beginning of next year in the rest of the territory.
However, be careful, when restarting the heating, it is dust mites and mold that can bother allergy sufferers.
You can check the pollen forecasts on our site, at the forecast level for your city, at the bottom of the page, as well as on the RNSA site (www.pollens.fr).
This newsletter is updated every Friday until the end of the pollen season.