This has been the worst year for winemakers that many can remember. The weather has been all wrong all year. First very cold (February) then very warm and dry (March) followed by very wet with frost and hail (April-May) and not very sunny (June-July) then another bout of hot and dry (August-September) and now very wet (October). By the end of September everyone had resigned themselves to a much reduced harvest of about 50% of normal, but the grape quality seemed quite high -- perhaps a bit low in sugar, but no disease. Winegrowers in areas who were able to harvest in late September and did so are happy(ish) -- last year one of 'our' wineries in Saint-Georges-sur-Cher (Touraine) got no sauvignon blanc at all due to the dry. This year he has good sauvignon blanc -- not in his normal quantity, but enough to make a worthwhile vintage.
Over in Vouvray it's a disaster. Many growers waited until around 10 October to start picking and the heavens have opened on them. Until a few of days ago it remained quite warm too, so the fungi were growing on the grapes while you looked at them. The original plan had been to leave the grapes as long as possible to try to achieve the best possible ripeness. They were also planning to make two passes through the vines, picking individual grapes by hand. This slows everything down, but was considered necessary, as the strange spring weather meant that individual bunches of grapes were a mixture of ripe and unripe berries. Flowering and pollination had been slow and intermittent earlier in the year, and the patchy development of the grapes is reflecting that now.
The worry will continue, as winemakers hope that their cellar stocks can compensate for this poor harvest. They need to be able to meet the needs of their regular customers or they will go elsewhere -- and not necessarily elsewhere in France, as all regions in France are reporting poor harvests.