Has today been a sneezy day? If so, which way was the wind blowing and could a cloud of pollen be to blame? For hay fever sufferers the best breeze comes from the sea. By contrast, being downwind of a meadow, moor or woodland can be a snuffly nightmare.

In the UK the prevailing winds are westerly and, having travelled over the Atlantic Ocean, they are virtually pollen free when they arrive on the west coast. But as the winds traverse the country they pick up pollen on their way, meaning that the east side of the country tends to have a higher pollen count than the west.

If the wind switches to an easterly, then the pollen count usually lowers in the east and rises in the west. But easterly winds are not always as pure as westerlies, and pine pollen has been known to hop over on the breeze from Norway.

Central England is the worst place for a hay fever sufferer to live. Whichever direction the wind blows it tends to be laden with pollen. Derby has had some of the highest pollen counts in the UK. In June 2001 a count of 1,024 grains of pollen per cubic metre was recorded; this was close to the record of 1,100 grains per cubic metre recorded in Cardiff in 1992.

A level of 50 grains per cubic metre is sufficient to cause hay fever symptoms in most people. And that is time to head for the beach perhaps; for some of us the sea air really is healthier.

Today's best video

Today in pictures

More from Weatherwatch

Our regular column investigating the stories behind the weather