Seoul, April 5 : Scores of flights were grounded on South Korea's Jeju Island on Wednesday due to dangerous wind conditions. The weather authorities issued alerts for high winds and wind shear, which refers to sudden changes in wind direction and speed, reports Yonhap News Agency. As of 9 a.m., the Jeju International Airport had reported the cancellation of 31 domestic flights. Of the 259 domestic and 14 international flights scheduled for the day, airlines cancelled 167 in advance. In the morning, wind gusts reached a peak of 11.8 meters per second in areas surrounding the airport. The wind is forecast to intensify to 12.8 to 23 mps in the afternoon. "The wind was blowing as strong as 25.7 mps, equivalent to a quasi-typhoon, over the airport, causing disruptions to aircraft operations," a weather official at the airport said. /IANS