Although the birch pollen season does not usually begin until mid-April, pollen counters began registering the grains during last weekend, when weather was unusually warm for the time of year.

The early start to the pollen season is linked to a mild spring and a sudden increase in temperature, according to Astma-Allergi Danmark, which issued a press statement after the weekend’s pollen counts.

The count reached as high as 31 in the west of the country by the end of last weekend, but was as low as 3 in Copenhagen.

“It’s still difficult to predict how the season will take shape, but if the weather continues with sun and warm temperatures, we can expect high pollen counts. We have already had record-high amounts of alder and hazel this spring,” Andrea-Pil Holm, a biologist who is responsible for the pollen counts, said in a press statement.

“On the other hand, cold weather and rain could set pollen levels back a bit,” Holm added.

Although weather patterns have since brought cooler air back to the country, forecasts currently suggest that warmer days could return next week.

Birch pollen is one of the worst culprits for people with pollen allergies.

An analysis has found that over half of the around one million people in Denmark who have pollen allergies are affected by it.

Pollen counts indicate the amount of pollen in the air at a given moment: in the case of birch, the level is low if the measurement is under 30; moderate if between 30 and 100, and high when over 100.

The country’s highest ever birch pollen counts were recorded on April 21st, 2014, with 4,696 in Copenhagen and 2,526 in Viborg.

Despite these relatively large values, a count of 100 is considered high because that is enough to provoke a reaction in all allergy sufferers.

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