A moderate Northeast Monsoon surge affected the region on 18 – 22 January 2013 during the wet phase of the Northeast Monsoon season. The surge was due to the strengthening of winds over the South China Sea. The rain was prolonged and widespread, intermittent and heavy at times with occasional windy conditions. The surge was most intense on 19 January, with the highest total rainfall of 134.7 mm recorded at Changi area.
Another surge occurred quite late into the Northeast Monsoon on 12 – 14 February 2013. This surge was weaker and brought moderate to heavy thunderstorms over Singapore on 14 February, with the highest rainfall total of 117.6 mm recorded at Seletar area.
