Chateau Cos d'Estournel and Cos Labory are two of the Bordeaux estates to have suffered from the weekend's hailstorms, which hit an estimated 900 hectares of vineyards.

The storms, which began on Friday morning (September 2nd), also affected Pessac Leognan, Grezillac and Saint Andre de Cubzac, Decanter reports.

"We have to be patient for a full assessment, but it seems likely that harvest dates will be brought forward, as there has been a lot of skin damage, which presents a risk of rot when combined with the recent hot weather," Bordeaux consultant Olivier Dauga told the publication.

Prior to the storms, Bordeaux was expecting yields between five and ten per cent higher than last year, and although this may now need to be revised slightly for some estates, Mr Dauga stressed that there is "no need to panic".

This year's Bordeaux harvest is one of the earliest on record, and Sylvie Cazes of the Union des Grand Crus de Bordeaux recently told The Drinks Business that growers are expecting another very good year.