One of the sails – measuring 37 feet long – was blown off and crashed through the roof of the adjacent building.

On Monday the sail was clearly visible to passers-by, with blue tarpaulin placed around the hole which had been left in the roof.

Now the working mill, which produces more flour than any other in Britain, stands with just four of its five sails.

Co-owner of the Willoughby Road mill and the building which was damaged, James Waterfield, refused to comment, saying he was too busy.

This is not the first time high winds have struck at the mill, but in 1990 severe storms had quite the opposite effect. Back then, the wind snapped through the mill's brake and set the machinery whirring. Almost three tonnes of flour were produced in one night – normally this would take a whole week to produce.

The tips of the sails move at a top speed of 30mph.

Boston weatherman Albert Kirkham said it had been extremely wet and windy over the weekend.

"It certainly has been windy – it was up to force six at times," he said.

"This would be even stronger out in the open."

He added: "It is very wet at the moment. Over the first weekend of the month there was 36mm of rainfall, and from Sunday to Monday morning there was 8.5mm."

Mr Kirkham said so far in November, there has been as much rainfall as he would expect for the whole month.