MT logo



Courtesy of the United States Coast Guard

The U.S. Coast Guard broadcasts National Weather Service highseas forecastsand storm warnings from four high seas communication stations in the SITOR(SImplex Teletype Over Radio) mode. These broadcasts are prepared cooperativelyby the Marine Prediction Center, Tropical Prediction Center and HonoluluForecast Office. Offshore and coastal forecasts are available in areassuch as Alaska. The International Ice Patrol also broadcasts from Bostonsharing the same transmitters.

The table below lists station locations and schedules. Transmissionrange is dependent upon operating frequency, time of day and atmosphericconditions and can vary from only short distances to several thousand miles.

U.S. Coast Guard SITOR text broadcasts are performed in FEC/SITOR modeB and is also known as Narrow Band Direct Printing (NBDP). SITOR/NBDP isan automated direct printing service similar to NAVTEX, but does not offerall of the same functionality such as avoiding repeated messages. In theU.S., SITOR/NBDP is not approved as an alternative to NAVTEX or SafetyNETfor fulfilling the Marine Safety Information (MSI) requirement of shipsrequired to be GMDSS (Global Maritime Distress and Safety System) equipped.

Coast Guard HF SITOR (NBDP) Broadcast ScheduleBoston, Massachusetts (NMF): 6314 (0000Z, 0100Z), 8416.5, 12579 and 16806.5 (1200Z, 1600Z) kHzStart Broadcast 0140Z 1630ZIce (Seasonal, ~Feb-Sep) 0030Z3 1218Z3Point Reyes, California (NMC): 8416.5 and 16806.5 kHzStart Broadcast 0005Z 1800ZHonolulu, Hawaii (NMO): 8416.5, 12579 and 22376 kHzStart (8/12/22 MHz) 0130Z 1730Z2 2030Z 2230Z1Start (8/12 MHz) 0330Z2 0430Z 0630Z 1 0730Z 1330ZGuam (NRV): 12579, 16806.5 and 22376 kHzStart Broadcast 0230Z1 0500Z 0900Z1 1500Z 1900Z 2315Z1 HYDROPAC navigation message, no weather2 NAVAREA navigation message, no weather3 International Ice Patrol, call letters NIK

Back to Monitoring Times homepage