Last month was the hottest May since weather forecasting began in Korea on a national scale in 1973. 
 
The Korea Meteorological Administration said the nationwide average temperature last month was one-point-two degrees higher than past years at 18-point-four degrees Celsius.
 
The agency says temperatures were low in early May with the influx of cold air but rose sharply later in the month as strong sunlight continued and warm air streamed in from the south.