Today is the day that legend has it shall determin the weather for the next 40 days. The ancient nursary rhyme goes like this:

St. Swithin's day if thou dost rain
For forty days it will remain
St. Swithin's day if thou be fair
For forty days 'twill rain nae mair.

The probable origin of the legend of continuious rain for 40 days and 40 nights proberly came about because when his body was moved it was accompanied by violent rain storms that lasted 40 days and 40 nights supossedly indicating he displeasure at being moved.

According to tradition Swithin had asked to be buried just outside the west door of the Old Minsterso that people would walk across it and rain fall on it. He died on 2nd July 862. However Bishop Ethelwold dug up his remains on 15 July 971 and moved his remains to a shrine in the cathedral. Miraculous cures were then associated with this event, which is why St Swithin's day not on his birth or death day.

Saint Swithin was a Saxon bishop

He was born in the kingdom of Wessex (now known as the West Country) and educated in its capital, Winchester. He was famous for charitable gifts and building churches. His feast day is 15 July and his emblems are rain drops and apples. 

St. Swithin was made Bishop of Winchester in 852 by Ethelwulf, son of Egbert. Swithin's only miracle during his lifetime was when an old lady's eggs had been smashed by workmen building a church. Swithin picked up the broken eggs, and, it is said, they miraculously became whole again. 

Saint Swithin is still seen as the patron of Winchester Cathedral.