Complex sentence: Whilst Kim moved across southern Burma as expected, it never moved into the Bay of Bengal, instead Kim moved northwards along the coast of Burma, parallel to the Arakan Mountain Range and gradually weakened.
Split into simpler sentences: Whilst Kim moved across southern Burma as expected, it never moved into the Bay of Bengal. Instead, Kim drifted northwards along the coast of Burma, parallel to the Arakan Mountain Range and gradually weakened.