By Evan Dawson, Managing Editor One day of rain can't ruin a year-long growing party, right? Despite the stellar conditions that have run from March to the fall, last Thursday's rains (up to four inches in parts of the Finger Lakes) threatened to soak the party. But at White Springs Winery on Seneca Lake, winemaker Derek Wilber explained why the rain is not likely to be enough to cause real trouble. "The real nightmare scenario is heavy rain followed by real warm temperatures," Wilber said at the end of a long harvest day in the winery. "Tropical storms can be…