WRF Sensitivity to Simulate EMP in the Diurnal Cycle of Precipitation over the North Coast of West Java

Abstract

The Early Morning Precipitation (EMP) over coastal region is an uncommon pattern in the diurnal cycle due to land-see breeze regular mechanism. This phase shift of diurnal cycle could hinder a numerical weather prediction to capture precipitation. This study aims to investigate sensitivity of WRF model on simulating EMP over north coast of West Java. Some cases (26 January 2006, 4 February 2008) representing heavy precipitation have been simulated in capturing EMP over the north coast of West Java to examine model sensitivity on convection scheme and domain size. The results showed the Betts-Miller-Janjic (BMJ) scheme could simulate EMP quite well on phase, whereas the Kain-Fritsch (KF) scheme capture out of phase on diurnal cycle. For model sensitivity on domain size, the larger domain displayed more realistically in phase to simulate EMP. For synoptic condition during heavy precipitation, it appeared that Cross Equatorial Northerly Surge (CENS) which is enhanced by South China Sea-Cold Tongue (SCS-CT) played main role to develop EMP.