Tropical Cyclones (TCs) are among the atmospheric
events which may trigger/enhance the occurrence of disasters to the society in
most world basins including the Southwestern Indian Ocean (SWIO). This study analyzed the dynamics and
the impacts of the Tropical Cyclone (TC) Idai (4th-21st March, 2019) which devastated most of the SWIO countries. The study used the
Reanalysis 1 products of daily zonal (u) and meridional (v) winds, Sea Surface
Temperatures (SSTs), amount of Precipitable Water (PRW), and relative humidity (Rh). The dynamics and movements of Idai were analyzed using the wind circulation at 850, 700, 500 and 200 mb, where
the TC dynamic variables like vertical wind shear, vorticity, and the mean
zonal wind were calculated using u and v components. Using the open Grid
Analysis and Display System (GrADS) software the data was processed into three-time
epochs of pre, during and post; and then analyzed to feature the state of the
atmosphere before (pre), during and post TC Idai using all datasets. The amount of precipitable water was used to map the rainfall on pre, during,
and post Idai as well as during its landfall. The results revealed that
dynamics of TC Idai was intensifying the weather (over Mozambique) and clearing
the weather equatorward or southward of 12°S, with low vertical wind shear over
the landfall areas (-3 to 3 m/s) and higher shear values (10 - 40 m/s)
northward and southward of the Mozambican channel. Higher moisture content (80
- 90%) and higher PRW (40 - 60 mm/day) mapped during Idai over the lowland
areas of Mozambique propagating westward. Higher low-
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