Graphical Abstract

• Tweet

Koralegedara, S. B., C.-Y. Lin, and Y.-F. Sheng, 2019: Numerical analysis of the mesoscale dynamics of an extreme rainfall and flood event in Sri Lanka in May 2016. J. Meteor. Soc. Japan, 97, 821-839.
https://doi.org/10.2151/jmsj.2019-046   Graphical Abstract with highlights

Plain Language Summary: Sri Lanka frequently experiences extreme rainfalls under the influences of monsoon system and atmospheric disturbances from the Bay of Bengal (BoB) in India Ocean. However, detailed analyses on both the synoptic and mesoscale dynamics in extreme events in Sri Lanka using numerical model are rare. This extreme rainfall event occurred as the cumulative effect of a sustained low-level convergence zone generated by an enhanced westerly monsoon flow and the circulation of the low pressure system (LPS) alongside a continuous supply of high-magnitude moisture, strong vertical motion, and orographic effects of the Central Mountains of Sri Lanka.

• Original PDF

Highlights:

• This study numerically simulated and examined the mechanism behind the heavy rainfall event that occurred in Sri Lanka from 14–17 May 2016.
• The results indicated that the observed extreme rainfall event over the western part of the island was the result of interactions among the following phenomena: 1). the LPS in the BoB, 2). moisture-rich westerlies from the Indian Ocean and the Arabian Sea, 3) persistent low-level convergence and 4). the orographic effect from the Central Mountains of Sri Lanka.