Synoptic and Dynamical Characteristics of Severe Cyclonic Storm ASANI May 2022
M. Sunanda *
Cyclone Warning Centre Visakhapatnam, India Meteorological Department, Ministry of Earth Sciences, Andhra Pradesh, India.
S. Prayek
Cyclone Detection Radar Machilipatnam, India Meteorological Department, Ministry of Earth Sciences, Andhra Pradesh, India.
Pravath Naskar
Meteorological Office, Port Blair, India and Meteorological Department, Ministry of Earth Sciences, India.
Kvs. Srinivas
Cyclone Warning Centre Visakhapatnam, India Meteorological Department, Ministry of Earth Sciences, Andhra Pradesh, India.
. Harshasoni
Cyclone Warning Centre Visakhapatnam, India Meteorological Department, Ministry of Earth Sciences, Andhra Pradesh, India.
Ch. Ramana
Cyclone Warning Centre Visakhapatnam, India Meteorological Department, Ministry of Earth Sciences, Andhra Pradesh, India.
S. Stella
Met Centre, IMD, Moes, A.P., India.
Karuna Sagar
Met Centre, IMD, Moes, A.P., India.
*Author to whom correspondence should be addressed.
Abstract
The synoptic and dynamical conditions for the genesis and intensification of tropical cyclone Asani are clearly highlighted in the present paper. The observationally favourable conditions for the genesis of Asani are high SST, 200 hpa STWJ, and weak vertical shear of horizontal wind, which enhanced the convection and intensified the system. The SCS Asani entered a region with lower SST and lower ocean heat content, causing it to weaken into a deep depression in the Bay of Bengal before making landfall. Because of the anticyclone over Indian landmass, Asani remained within 50 km of the coastline for the entire day; as a result, the system moved slowly and remained nearly stationary. The slow movement led to upwelling of sea water and rainfall over the sea, leading to further cooling of the sea surface. There was also land interaction, thereby increasing friction for a longer period. There was a cold and dry air incursion from the Indian Land region in the middle and upper troposphere, leading to weakening.
Keywords: SST, warm dry winds, ridge, ocean heat content, surface latent heat flux