You can put away the sunblock, because St Swithin says it might rain until September

For if folklore is right, Britain is heading for another disappointing summer.

Yesterday was St Swithin's Day, which traditionally predicts the weather for the next six weeks.

Determined: Children on Bournemouth beach ignore the less than perfect conditions

According to the rhyme: 'St Swithin's day, if thou dost rain, for forty days it will remain; St Swithin's day, if you be fair, for forty days 'twill rain nae mair.'

If yesterday's weather is any guide, the next few weeks will see a mixture of sunny spells and cloud, heavy showers and light drizzle, and temperatures ranging from the chilly to the clammy.

After a run of mostly reasonable summers over the last decade - with the notable exception of last year - the return of the typical British summer in time for most school holidays might come as a shock.

The origins of the St Swithin's Day weather proverb are lost in time. But many believe it was inspired by the events surrounded the reburial of the saint a century after his death.

Folklore: The weather on St Swithin's Day is said to predict how it proceeds for the next 40 days

According to legend, St Swithin had asked for a humble grave outside Winchester Cathedral, so it would be exposed to the rain and the feet of his followers.

But in the tenth century, his remains were moved to a shrine inside the cathedral, where he had been bishop.

The move was hampered by horrendous storms which lasted for 40 days - causing the superstitious locals to believe that they had been cursed by the irritated saint.

If the curse of St Swithin holds true, the next six weeks will see more unsettled weather. The South West woke up yesterday to downpours, the North had showers in the afternoon, and parts of Wales and the South had a damp evening.

Dismal: If the rhyme holds true, Britain could be heading for yet another disappointing summer

'Most places had some rain, drizzle or showers,' said the Met Office's Sarah Holland. While the hard-headed meteorologists at the Met Office would usually have little time for a ninth-century saint, for once their official prediction appears to support the legend.

They are forecasting a long, wet summer. 'We expect it to be a typical British summer with rainfall and temperatures a little bit above average,' added Miss Holland. 'There are no signs of any long, hot spells yet, although the second half of July might be a little warmer and drier.'

This summer's unsettled weather is influenced by La Nina - the cooling of the Pacific. The phenomenon has moved the jet stream - the band of fast-moving air high in the atmosphere - further south than normal, bringing cooler, wet conditions.

Like many pieces of weather folklore, the St Swithin's Day proverb contains seeds of truth. By mid-July, British weather has usually settled down for the summer and rarely swings from one extreme to another.

However, despite searching through 55 years of records, researchers have shown that rainfall on St Swithin's day has never led to 40 days of rain.

In 1913, 15 hours of heavy rain deluged London on St Swithin's Day. But it rained on only nine of the following 40 days. The closest the saying has come to being accurate was in 1990, when after a hot, sunny July 15, it rained on 37 of the following 40 days.

The last few months have seen a mixed bag of weather. May began with a warm fortnight followed, in England and Wales, by rain and cool temperatures. Despite a remarkably rain-free Wimbledon fortnight, June had average temperatures, rainfall and sunshine. The first half of July has been wetter than average.

The hottest summer on record was 2006, while 2003 saw temperatures of 38.5C (101F) in Kent. Last summer, however, was the wettest on record for England.