St Swithin's Day: What is it and why do people think the weather today is important?

Last updated at 05:23
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BBC Weather's Matt Taylor dispels the myth of St Swithin.

If you're on your summer holidays or looking forward to breaking up from school soon, you're probably hoping for a bit of sun. But what if it rained non-stop for 40 days?

Well, today is St Swithin's day. It takes place on 15 July each year, and according to traditional folklore, whatever the weather is like on St Swithin's Day - whether rain or sunshine - it will continue for the next 40 days and 40 nights.

But where does this legend come from and is there any truth to it?

What is the story of St Swithin?

The old poem goes like this...

"St Swithin's Day, if it does rain

Full forty days, it will remain

St Swithin's Day, if it be fair

For forty days, t'will rain no more"

St-Swithin.Getty Images

Swithin was a man born in or around the year 800. He became Bishop of Winchester.

Unlike other religious figures, he asked not to be buried in a prominent place within Winchester Cathedral, but outside in a simple tomb "where the sweet rain of heaven may fall upon my grave".

The legend says after his remains were moved inside there was a great storm and it rained for many weeks after.

Is there any truth to the folklore?
Weather-icons.Getty Images

According to the old saying, if it rains on St Swithin's Day it will rain for the next 40 days. If St Swithin's Day is dry, the next 40 days will also be dry.

No one takes the prediction literally - in fact, few take it seriously! - and there is definitely no statistical evidence to support the claim.

Weather experts says that since records began in 1861, there has never been a record of 40 dry or 40 wet days in a row following St Swithin's Day.

So while we might not like 40 days of rain and 40 days of sun sounds fun, neither is likely to happen!