The Joint Typhoon Warning Center (JTWC) is a combined United States Navy Navy and United States Air Force Air Force task force based at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii. Its core mission is to detect, monitor and forecast tropical cyclones that may affect U.S. military operations and other government interests across the Pacific and Indian Ocean basins.
Responsibilities and scope
JTWC issues warnings, forecasts, and storm analyses for tropical disturbances and named cyclones. Its products include position and intensity estimates, forecast tracks, and formation alerts. These products support naval and air operations as well as planning for vessels, aircraft, and installations.
Operations and methods
Analysts at JTWC combine satellite imagery, automated and human analyses, numerical weather prediction models, surface observations and, when available, aircraft reports to assess storm structure and intensity. Forecasts emphasize short- to medium-term track and intensity changes and are updated on a regular schedule when systems are active.
Typical products produced by JTWC include:
- Tropical cyclone advisories and warnings
- Formation alerts and track forecasts
- Best-track summaries and periodic reports used for historical records
Users of JTWC output include U.S. Department of Defense agencies, military planners, merchant shipping, aviation interests and, informally, some civilian meteorological services in the region.
Although JTWC provides authoritative warnings for U.S. government purposes, other national and regional meteorological agencies — such as those designated by the World Meteorological Organization — issue official warnings for their own territories. One notable technical difference is wind averaging: JTWC reports 1-minute sustained winds (the same convention used by the U.S. National Hurricane Center), whereas some regional agencies use 10-minute averages.
JTWC is staffed by military meteorologists and civilian specialists who coordinate with international partners to maintain situational awareness of tropical cyclone activity throughout the areas of interest.