The prolonged rainy season has put a damper on beer sales. At Shinsegae E-Mart, beer sales increased 1.4 percent in June but fell 3.8 percent in the first half of July compared to a year earlier. Sales in the first week of this month (from June 29 to July 5) dropped only 1.4 percent from a year ago, but plunged 6.3 percent in the second week. In contrast, soju sales inched up 1.5 percent in June and jumped 5.1 percent in the first half of July.

At Lotte Mart, beer sales rose 6.7 percent in the first week of July but declined 4.3 percent in the second.

The situation is similar at convenience stores. GS25's beer sales climbed 11.5 percent in June but added only 5.1 percent on-year in the first half of July, while soju sales increased 12.6 percent in June and surged 18.7 percent during the first 15 days of July.

Beer sales are usually strong this time of year with the end of the rainy season, but this year the continued heavy rains have depressed sales, industry sources say. According to the Korea Meteorological Administration, it has rained for nine days in Seoul so far this month, with three days having precipitation close to 100 mm or more. The same period last year recorded not even one day with precipitation of more than 100 mm.