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Jet streaks

Local wind speed maximum within a jet stream.

Jet stream

Flat tubular, quasi-horizontal, current of air embedded in the mid-latitude westerlies, near the tropopause, whose axis is along a line of maximum speed. This narrow stream of strong wind in the atmosphere is characterized by great speeds and strong vertical and horizontal wind shears. There is more than one jet stream, being the polar front jet stream the predominant. Currently, a jet stream is indicated in any place where it is determined that wind speed equals or exceeds 50 knots.

Joint Typhoon Warning Center (JTWC)

Is a joint task force, between the United States Navy and the United States Air Force, located in Pearl Harbor, Hawaii, that is responsible for issuing tropical cyclone (typhoons) warnings in the North West Pacific Ocean, South Pacific Ocean and Indian Ocean.