First it was the rain, and now it's pollen that will start to alter the laundry habits of Sydneysiders.

Hanging sheets or clothing outside to dry on high pollen days is one of the worst things people suffering from pollen-related allergies can do.

Spring means seasonal agony for some allergy sufferers. Credit:Marco Del Grande

From Friday, Sydney residents can expect as many as four days of high pollen count in a row, the first sustained burst this season, Brett Dutschke, senior meteorologist with Weatherzone, said.

"It may get to 'very high' or 'extreme' by late next week," Mr Dutschke said, adding that there was a good chance of Sydney's temperatures reaching the mid- to high-20s by then.