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Morakot was embedded in a moderately sheared environment and had become highly asymmetric in structure as it approached Taiwan, with virtually all the deep convection confined to the southern semi-circle. Little significant rainfall was recorded to the north of the typhoon's track. The changes in vertical structure of the cyclone before and during its passage over the island, combined with upslope flow along the westward slopes of the mountains, were critical in the development of the intense, prolonged rainfall.
Operational forecast models displayed mixed results in the relatively complex synoptic environment during the landfall phase of Morakot. Here, we present the results of simulations of Morakot utilising a high resolution mesoscale model, with finest grid scale of 1 km. The results of these simulations, together with direct observations, are analysed to investigate the structural aspects of the cyclone and their predictability. Further, the effects of the environment and complex topography on intensity and motion in the landfall phase, and mechanisms behind the development and prolonged maintenance of the intense rainfall, will be investigated through a series of sensitivity experiments. The model results will be compared with a wide range of observational datasets.