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Broadcast Warningsspacer


In support of the Global Maritime Distress and Safety System (GMDSS), Broadcast Warnings are promulgated by the Worldwide Navigational Warnings Service (WWNWS) to provide rapid dissemination of information critical to navigation and the safety of life at sea.

Navigational Warnings are issued regularly and contain information about persons in distress, or objects and events that pose an immediate hazard to navigation. The four types of Navigational Warnings - NAVAREA IV, HYDROLANT, NAVAREA XII, and HYDROPAC - are categorized by their location.
View graphic of Navigational Warnings limits.

HYDROARC Warnings are issued for the Arctic region not covered by HYDROLANT and HYDROPAC messages. 

Broadcast Warning messages are also available as a Google Earth (.kmz) file: Download file

Special Warnings and Maritime Administration (MARAD) Advisories are issued infrequently and contain information about potential hazards caused by the global political climate.

The Daily Memorandum is issued each week day, excluding federal holidays, and contains a summary of all Broadcast Warnings and Special Warnings promulgated during the past 24-72 hours. The Atlantic Edition includes HYDROLANT and NAVAREA IV Warnings, while the Pacific Edition includes HYDROPAC and NAVAREA XII Warnings. Both editions include Special Warnings issued during the same period.

Use the query form below to retrieve Broadcast Warnings from the on-line database.


  Current Warning Messages
Warning Type Current Warning
NAVAREA IV 845 / 2015
NAVAREA XII 342 / 2015
HYDROARC 356 / 2015
HYDROLANT 2512 / 2015
HYDROPAC 3316 / 2015
Special Warnings 133 / 2015
MARAD Advisories 2 / 2015
   Daily Memorandum
 Atlantic Edition (4 KB)
 Pacific Edition (1 KB)
Last Database Update Occurred: 081923Z OCT 2015
Warning type to Query: Query Directions