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AIS Weather Conditions-gctid385659

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    AIS Weather Conditions-gctid385659

    Has anyone run across an application that displays the wind speed and direction sent directly by the AIS transponders on the commercial ships? I know about the internet based ship maps which show the wind conditions from the ships. All the chart plotting programs that I'm aware of (Nobeltec Odyssey, Navionics etc.) primarily focus on speed, direction and closest point of approach from AIS, but not the current wind information. I think it would be invaluable to see what the ships within 15-25 miles are experiencing when you're approaching a crossing such as around Cape Caution, Johnstone Strait or through Georgia Strait.



    Sea Shanti

    1990 3288MY

    Have not seen any ship reporting but do use other sources. Check out the following for example. Find Puget Sound for example, then click on a weather reporting station. Next page then has wind history, and a wind forecast every three hours for next four days. There are similar Canadian web sites.
    Started boating 1965
    Bayliners owned: 26 Victoria, 28 Bounty, 32, 38, and 47 since 1996


      Not exactly what you wanted, but I find the WSF info usefull
      Partner in a 1999 4788

      Seattle, WA


        I do not believe weather information is part of the AIS broadcast data set for any size vessel.

        For regional weather check out the NOAA bouy broadcasts.
        Jim McNeely
        New Hope a 2004 Bayliner 305 Sunbridge Express Cruiser
        Twin 5.7s with Bravo2 drives
        Brighton, Michigan USA
        MMSI # 367393410


          Broadcast information An AIS transceiver sends the following data every 2 to 10 seconds depending on a vessel's speed while underway, and every 3 minutes while a vessel is at anchor:
          • The vessel's Maritime Mobile Service Identity (MMSI) ÔÇô a unique nine digit identification number.
          • Navigation status ÔÇô "at anchor", "under way using engine(s)", "not under command", etc.
          • Rate of turn ÔÇô right or left, from 0 to 720 degrees per minute
          • Speed over ground ÔÇô 0.1-knot (0.19 km/h) resolution from 0 to 102 knots (189 km/h)
          • Positional accuracy:
            • Longitude ÔÇô to 0.0001 minutes
            • Latitude ÔÇô to 0.0001 minutes
            • Note that this positional accuracy is not adequate to tell 2 personal watercraft apart.
          • Course over ground ÔÇô relative to true north to 0.1┬░
          • True heading ÔÇô 0 to 359 degrees (for example from a gyro compass)
          • UTC Seconds ÔÇô The seconds field of the UTC time when these data were generated. A complete timestamp is not present.

          In addition, the following data are broadcast every 6 minutes:
          • IMO ship identification number ÔÇô a seven digit number that remains unchanged upon transfer of the ship's registration to another country
          • Radio call sign ÔÇô international radio call sign, up to seven characters, assigned to the vessel by its country of registry
          • Name ÔÇô 20 characters to represent the name of the vessel
          • Type of ship/cargo
          • Dimensions of ship ÔÇô to nearest meter
          • Location of positioning system's (e.g., GPS) antenna on board the vessel - in meters aft of bow and meters port of starboard
          • Type of positioning system ÔÇô such as GPS, DGPS or LORAN-C.
          • Draught of ship ÔÇô 0.1 meter to 25.5 meters
          • Destination ÔÇô max. 20 characters
          • ETA (estimated time of arrival) at destination ÔÇô UTC month/date hour:minute
          • optional : high precision time request, a vessel can request other vessels provide a high precision UTC time and datestamp

          [edit] Detailed description: Class B units

          Class B transponders smaller, simpler and lower cost than Class A transceivers. Each consists of one VHF transmitter, two VHF Carrier Sense Time Division Multiple Access (CSTDMA) receivers, one of which is multiplexed with the VHF Digital Selective Calling (DSC) receiver, and a GPS active antenna. Although the data output format supports heading information, in general units are not interfaced to a compass, so this data is seldom transmitted. Output is the standard AIS data stream at 38.400 kbit/s, as RS232 and/or NMEA formats. To prevent overloading of the available bandwidth, transmission power is restricted to 2 W, giving a range of about 5ÔÇô10 mi.

          At the time of writing (November 2009) almost all Class B units use boards from Software Radio Technology (SRT). Exceptions to this are Furuno, AMEC, Weatherdock and Vesper Marine.

          Four messages are defined for class B units:

          [edit] Message 14: Safety Related Message

          This message is transmitted on request for the user ÔÇô some transponders have a button that enables it to be sent, or it can be sent through the software interface. It sends a pre-defined safety message.

          [edit] Message 18: Standard Class B CS Position Report

          This message is sent every 3 minutes where speed over ground (SOG) is less than 2 knots, or every 30 seconds for greater speeds.

          MMSI, time, SOG, COG, longitude, latitude, true heading

          [edit] Message 19: Extended Class B Equipment Position Report

          This message was designed for the SOTDMA protocol, and is too long to be transmitted as CSTDMA. However a coast station can poll the transponder for this message to be sent.

          MMSI, time, SOG, COG, longitude, latitude, true heading, ship type, dimensions.

          [edit] Message 24: Class B CS Static Data Report

          This message is sent every 6 minutes, the same time interval as for Class A transponders. Because of its length, this message is divided into two parts, sent within one minute of each other.

          Note that this message was defined after the original AIS specifications, so some Class A units may need a firmware upgrade to be able to decode this message.

          MMSI, boat name, ship type, call sign, dimensions, and equipment vendor id.
          Jim McNeely
          New Hope a 2004 Bayliner 305 Sunbridge Express Cruiser
          Twin 5.7s with Bravo2 drives
          Brighton, Michigan USA
          MMSI # 367393410


            Jim hit the nail on the head. AIS does not support weather messages.


              What confuses me is that when you go to


              which uses the AIS information transmitted from the ship to track it and click on the details from the ship it shows you the following for the Victoria Clipper which includes wind speed and direction. I assumed that it was from the ship although it's possible that the web site inserted the weather data based on nearby weather stations or buoys. Will check into it further.

              Thanks for the responses.


              Sea Shanti

              1990 3288MY

              Vessel's Details

              Ship Type: Passengers ship

              Year Built: 1993

              Length x Breadth: 36 m X 10 m

              Gross Tonnage: 478, DeadWeight: 50 t

              Speed recorded (Max / Average): 35.1 / 26.9 knots

              Flag: Bahamas [BS]

              Call Sign: C6YL9

              IMO: 9059999, MMSI: 311037800

              Last Position Received

              Area: Pacific North

              Latitude / Longitude: 48.27366˚ / -123.0534˚ (Map)

              Currently in Port:

              Last Known Port: SEATTLE

              Info Received: 0d 0h 1min ago

              Current Vessel's Track

              Wind: 8 knots, 284┬░, 13┬░C