An announcement that a tropical storm or tropical storm conditions pose a threat to coastal areas generally within 36 hours. A watch should normally not be issued if the system is forecast to attain hurricane strength. Same as a Hurricane Warning, except winds of 63 to 177 kilometres per hour are expected. A kink or bend in the normally straight flow of surface air in the tropics which forms a low pressure trough, or pressure boundary, with showers and thunderstorms. Can develop into a tropical cyclone.
All weather occurs in the troposphere.
A hurricane in the north Pacific west of the International Date Line. A small scale current of air with vertical motion. If there is enough moisture, then it may condense, forming a cumulus cloud and possibly thunderstorms. The opposite of a downdraft. Vertical wind shear can weaken or destroy the cyclone by interfering with the organization of deep convection around the cyclone centre.