Cooperative Institute for Research in the Atmosphere

Satellite Use at Joint Typhoon Warning Center (JTWC)

The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command in Pearl Harbor, Hawaii. 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 Organization’s (WMO) rules for storm names and acknowledged guidelines for intensity of tropical cyclones, 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 Scale). The JTWC is not one of the WMO designated Regional Specialized Meteorological Centers, nor one of its Tropical cyclone warning centers, as its main mission is to support the United States government agencies.

JTWC monitors, analyzes, and forecasts tropical cyclone formation, development, and movement year round. Its area of responsibility covers 89% of the world’s tropical cyclone activity.

The center is staffed by about 37 U.S. Air Force and Navy personnel. JTWC uses several satellite systems and sensors, radar, surface and upper level synoptic data as well as atmospheric models to complete its mission.