The ministry expects the 2013 harvest to top out at 43.5 million hectoliters. The 10-year average is 45.5 million.
In Burgundy, some vintners in the prestigious Beaune region said devastating hailstorms in July caused near catastrophic damage to their vines and destroyed their crops. A few weeks later, similar storms pelted Bordeaux with hail the size of pigeon's eggs.
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It's not just quantity of the grapes, but also the quality that is lacking, according to FranceAgriMer. Tests showed low sugar content, which means the resulting wines will have less alcohol.
The weather also wreaked havoc on vineyards in Austria and parts of Greece.
In Vienna, the Austrian wine marketing board blamed a combination of hail, drought, and poor weather during spring flowering for a smaller harvest, especially of its flagship varietal, Gruner Veltliner.
The Union of Santorini Cooperatives, which represents many of the Aegean island's grape growers, reported: "The performance of the vines is 200 percent lower than last year..." The group, in its harvest report, blamed "a fierce windstorm" that led to the destruction of many young shoots and compromised pruning for the poor showing.
"We won't have as much wine," Ted Diamantis, of Chicago-based Diamond Wine Imports, said after returning from a trip to the various wineries whose goods he imports to the United States.
Greece has a variety of climates. In the north, the harvest has not quite begun, but everything is looking very good, so the difference in harvests is really dependent on the weather, Diamantis said.
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Perfectly ripened grapes, later harvests
But in parts of Spain and Italy, winemakers said they were having good harvests with lots of perfectly ripened grapes. They were just 10-to-15 days later than usual.
In Umbria in Italy, Marco Caprai, head of Arnaldo Caprai winery, said he expected to harvest about 50 percent more grapes than last year. He thinks the late harvest will result "in wines that are not too rich in alcohol and very balanced."
Beatrice Contini Bonacossi, whose family has owned the Villa di Capezzana estate in Tuscany for almost 100 years, said although the harvest has not ended, at the moment she is pleased.
"I can safely say that this year we can look forward to a nice quantity of grapes compared with last year, which was a relatively small vintage," she added.
Across the Atlantic, U.S. winemakers are harvesting their grapes two-to-three weeks early.
"Everything is coming in a lot earlier, my Pinot Noir. My last Pinot Noir pick is done already. Normally, I don't even start to pick that until the 14th or 15th of September," said Kathleen Inman, whose family owns a vineyard in California's Russian River Valley, part of Sonoma County.
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Across the Mayacamas Mountains in Napa Valley, Cain Winery's vintner Chris Howell said harvests of his Cabernet Sauvignon and Merlot were going to be earlier.
"This year is not as perfect a year as last year ... But this year, the harvest looks good," he said.
Randall Grahm, who started Boony Doon Vineyards on California's Central Coast 40 years ago, said the harvest was going reasonably well with grapes from the warmish regions appearing about 10 days earlier than normal.
"But (that's) by no means the earliest I've ever seen," he said.
Winemakers in Washington State, which has had second warmest summer on record, also expect an early harvest. Heat decreases the amount of time grapes take to ripen. This means the berries are smaller than usual and the flavors more concentrated.