BOUNDARY-LAYER RADAR OBSERVATIONS OF THE PASSAGE OF THE CONVECTION CENTER OVER SERPONG, INDONESIA (6-DEGREES-S, 107-DEGREES-E) DURING THE TOGA-COARE INTENSIVE OBSERVATION PERIOD

An L-band (1357.5 MHz) boundary layer radar (BLR) has been in continuous successful operation at Serpong, Indonesia (6.4 degrees S, 108.7 degrees E) for more than two years from November 1992, including the Intensive Observation Period (IOP) of TOGA COARE (November 1992-February 1993). We found a striking reversal of the wind direction from easterly to westerly at the beginning of December 1992. It was confirmed from geostationary meteorological satellite (GMS) observation data that this reversal was associated with an eastward movement of the convection center (a super cluster) situated between the Indian Ocean monsoon (westerly) dominant area and the Pacific Ocean trade wind (easterly) dominant area. The lower-tropospheric wind variations associated with (super) cloud clusters are presented, and some differences are found between the eastern and western sides of the convection center (corresponding respectively to the easterly and westerly regimes; or to the dry and rainy seasons).