The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command located in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South Pacific Ocean, and Indian Ocean for all branches of the U.S. Department of Defense and other U.S. government agencies. Their warnings are intended for the protection of primarily military ships and aircraft as well as military installations jointly operated with other countries around the world.
JTWC adheres to the World Meteorological Organisation's (WMO) rules for storm names and adheres to acknowledged guidelines for intensity of tropical cyclones and tropical storms, with the exception of using the U.S. standard of measuring sustained winds for 1-min instead of the 10-min span recommended by the WMO (see Saffir-Simpson Hurricane Wind Scale (SSHWS)). The JTWC is not one of the WMO designated Regional Specialized Meteorological Centres, nor one of its Tropical cyclone warning centres, as its main mission is to support the United States government agencies. JTWC monitors, analyses, and forecasts tropical cyclone formation, development, and movement year round.