19 May 2004
Onset of this year's South China Sea Summer Monsoon to occur soon
Tropical cyclone 2B is about to make landfall over Myanmar (Fig. 1). This therefore sets the stage for the onset of the South China Sea summer monsoon. The ECMWF forecast charts shows the subtropical high to have retreated east of the Philippines by Friday, 21 May (Fig. 2). The surface forecast chart for 22 May shows a trough over the South China Sea (Fig. 3), which may be from a trough currently over southern China (Fig. 4). In addition, the low pressure currently off the coast of Vietnam may intensify and move northeastward into the central South China Sea . Either one will provide the necessary trigger for the onset. Thus, it is likely that the onset of the South China Sea summer monsoon will occur around 22 May, which is slightly later than normal (around 15-20 May).
Fig. 2.
