Monitoring of GPS Precipitable Water Vapor During the Severe Flood in Kelantan

Problem statement: This study mainly discusses the possibility of PWV derived from GPS data for monitoring of water vapor changes during the severe flood due to heavy rainfall. There are two cases of heavy rainfall recorded during the winter monsoon in November 2009 at Kuala Krai, Kelantan. Approach: The first and second cases were sustained for 3 days from 4-6 November and 7 days from 18 until 24 November with recorded maximum daily rainfall more than 180 mm and 220 mm, respectively. However from the Malaysia Meteorology Department (MMD) report, only the second case was caused the severe flood. PWV and the surface meteorological data for both cases showed a significant response to the heavy rainfall. Results: During the severe flood, PWV was observed decreased of about 3.52 mm. Conclusion: We highlighted that the widespread and enormous cumulonimbus cloud cluster sheltered the area due to cold surge during the winter monsoon can cause the unnatural peak on PWV during the heavy rainfall.