[A-AS07] Analyses and Prediction of Extreme Weather and Climate in Southeast Asia

[AAS07-P03] Case studies of heavy rainfall observed in the Philippines and Malaysia during December 15-18, 2021

*Hisayuki Kubota¹, Yukihiro Takahashi¹, Mitsuteru Sato¹ (1.Hokkaido University)

Keywords:Tropical cyclone, Heavy rainfall, Madden-Julian Oscillation

Tropical cyclone (TC) Rai hit southern Philippines on December 16, 2021. More than 200 mm of heavy rainfall were observed in Mindanao and Bohol Islands of Philippines in two days during December 15 to 16, 2021. On the other hand, the amount of heavy rainfall reached 759 mm in three days in Kuantan of Peninsula of Malaysia during December 16 to 18, 2021. It is associated with the passage of another tropical depression. In this study, we focus on the heavy rainfall occurred in the Philippines and Malaysia during the same period in December 15 to 18, 2021 and analyzed the large-scale conditions for the heavy rainfall in Southeast Asia.
Madden-Julian oscillation was active over the equatorial western Pacific during December. Convections were active over the equatorial region of Southeast Asia. Two TCs were generated at east of Philippines during the end of November and mid-December. When the latter TC Rai was generated at east of Philippines, another circulation was formed around Borneo Island on December 13. Japan Meteorological Agency and Joint Typhoon Warning Center declared this disturbance as tropical depression. Both disturbances propagated westward and hit southern Philippines and Peninsula of Malaysia on December 16. Further analysis will be conducted to investigate the large-scale condition for heavy rainfall.