Abstract
Heavy rainfall over Malaysia occurs predominantly during the northeast monsoon season. Outbreaks of cold polar air over the South China Sea, known as cold surges, contribute to the onset of northeast monsoon precipitation. This study uses gridded reanalysis data from NCEP/NCAR Reanalysis Project 1 to calculate a cold surge index. This index is then compared with precipitation data for 4 surface stations from the World Monthly Surface Station Climatology (WMSSC) dataset. For Peninsular Malaysia, findings show that the cold surge index has the strongest inverse correlation with precipitation amounts at Kota Bharu and Kuantan stations from December to February (DJF). For the west coast of Sarawak, results for Kuching and Sibu stations show a similar inverse correlation from January to April (JFMA). The temporal difference suggests different cold surge flow types affecting each part of Malaysia. On the other hand, the similar inverse correlation relationship could imply that stronger southward-moving component of the cold surge winds bring heavier precipitation to both parts of Malaysia.