High temps over long weekend to lead to peak pollen next week

There will be a lot of sun on Ascension Day, but also clouds and slightly cooler temperatures than usual at between 13 and 17 degrees. It will be warmer from Friday, and on Sunday or Monday, the mercury will rise to 25 degrees or higher for the first time this year, according to WEER.nl. The expected summer temperatures will also lead to a peak in grass pollen next week, warned the Leiden University Medical Center (LUMC).

It was cold in the night from Wednesday to Thursday, with frost on the ground in several places in the country. Ascension Day started sunny, with cumulus clouds forming later. It will remain dry, and the coming night will cool down considerably again, with again some frost on the ground.

Temperatures will rise to between 18 and 20 degrees on Friday, WEER.nl reports. It will be summery from Sunday, but there may be a local shower or thunderstorm. Summer temperatures are also expected on Monday and Tuesday, accompanied by some heavy rain and thunderstorms inland.

From Wednesday, it will be dry again, and a peak in the concentrations of grass pollen - one of the main causes of hay fever in the Netherlands - is expected. “Due to the warm and, above all, very humid weather so far this year, the grasses are looking good. Good for the grasses, which bloom profusely, resulting in high grass pollen concentrations. But less good for people with hay fever,” said the LUMC.

Pollen concentrations have been remarkably low in the past two weeks. The two pollen counting stations, at the LUMC and the Elkerliek Hospital in Helmond, have counted grass pollen concentrations of about five pollen per cubic meter of air in recent weeks. At a pollen concentration of ten per cubic meter of air, people with a pollen allergy get complaints. In the peak period, with dry weather, the concentration can rise to several hundred pollen per cubic meter of air.

The pollen peak is expected to last until early July.