Typhoons function as vast systems of extraordinarily low pressure, acting as atmospheric vacuums that draw in surrounding air masses. Thiruvananthapuram: Torrential rainfall continuing across Kerala is being driven partially by the distant influence of Typhoon Dolphin in the Pacific Ocean, meteorologists have reported. Weather officials anticipate that as the storm dissipates over land, the intense rainfall gripping Kerala will begin to subside. Typhoons function as vast systems of extraordinarily low pressure, acting as atmospheric vacuums that draw in surrounding air masses. The India Meteorological Department (IMD) predicts that rainfall across Kerala should begin to ease from Sunday onwards as these combined weather systems weaken.