  Tropical Cyclone Viyaru, formerly known as Cyclonic Storm Mahasen was a
rapidly intensifying, category 01B storm that made landfall in Chittagong,
Bangladesh on the 16th of May, 2013. In this study, the sensitivity of
numerical simulations of tropical cyclone to cumulus physics parametrization is
carried out with a view to determine the best cumulus physics option for
prediction of the cyclones track, timing, and central pressure evolution in the
Bay of Bengal. For this purpose, the tropical cyclone Viyaru has been simulated
by WRF ARW in a nested domain with NCEP Global Final Analysis(FNL) data as
initial and boundary conditions. The model domain consists of one parent domain
and one nested domain. The resolution of the parent domain is 36 km while the
nested domain has a resolution of 12 km. Five numerical simulations have been
done with the same micro-physics scheme (WSM3), planetary boundary layer
scheme,NOAH land surface scheme but different Cumulus Parametrization scheme.
Four cumulus Parametrization schemes are KF, BMJ, GF and Tiedtke and one
simulation was done without any cumulus physics scheme. The results of model
simulations are compared with corresponding analysis or observation data. For
best result data provided by Joint Typhoon Warning Center and NASA tropical
cyclone center was used as observed for comparison. After the study it was
found that tracks, intensity, wind speed, precipitation, and central pressure
of the cyclone have sensitive result with different cumulus physics schemes.
