(TheLocal) - For most people in France the miserable cold and wet spring is a just a distant memory thanks to the return of the sun in July and August. But it is still a source of frustration for the country's wine growers who are facing one of the worst harvests in decades.

France is facing one of its poorest wine grape harvests in four decades, forecasts showed on Wednesday, due to a cold and rainy spring and severe hail storms.

The 2013 harvest is expected to reach just 43.5 millions hectolitres - well below the 10-year average of 45.4 million, according forecasts from the FranceAgriMer public agricultural service.

That would make the 2013 harvest one of the worst in 40 years and only a slight improvement on last year's record low harvest of 41.4 million, according to Jerome Despey, head of FranceAgriMer's viticulture section.

He said cool temperatures and excessive rains contributed to a particularly poor harvest.

Despey added that early tests also showed low sugar content.

"Sugar hasn't developed in the grapes and we'll have much lower (alcohol) levels than in previous years," he added.

Forecasts released by the agriculture ministry earlier this month, before devastating storms in Bordeaux, had already predicted France would experience one of the smallest harvests in 40 years in 2013.