Joint Typhoon Warning Center
The Joint Typhoon Warning Center (JTWC) is a division of the United States Navy's Navy Pacific Meteorological and Oceanography Center in Pearl Harbor, Hawaii. The JTWC is responsible for the observation of typhoon, tropical storm, tropical cyclone, tropical depression, hurricane and tropical wave weather phenomena between 140–180 degrees West longitiude in the North Pacific Ocean. While the aforementioned area is the primary JTWC area of responsibility, the JTWC issues warnings for tropical cyclones outside of this area if Department of Defense assets are threatened.
JTWC adheres to the World Meteorlogical Association's rules for storm names and adheres to acknowledged guidelines for intensity of hurricanes and tropical storms.