Rain Detection using Himawari-8 Imagery; Case Study Singkawang West Kalimantan

Abstract

The occurrence of convective activity often appears in a localized area and short duration. The formation of a low cloud might give an insight into the formation of bigger cumulus that can be seen as a Convective Initiation (CI) and if constantly developing it may lead to a bigger cloud with extreme rainfall. Detection of convective activity that leads to extreme rainfall is important to people who live near shore and areas that prone to flood. Himawari-8 imagery and data from an automatic weather station in Singkawang, West Kalimantan, was applied to detect short time, low-intensity rainfall that had been observed in the equator, near shore, during midnight and early morning. The appearance of CI was analyzed using rapid cloud-top cooling based on Himawari-8 imagery. It was found that the observed rainfall was in agreement with the cloud formations. Those data were validated by three days of a rain event with maximum cumulative rain of 30 mm observed in a single day. There was also appeared a small low cloud that grows into a bigger cloud above the observed area.