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Marine Weather Information

The information below should assist you with your passage planning and making your sailing a pleasure. A lot of information is to assist in getting the forecasts etc via the internet and more importantly, via Sailmail or Winlink, that is, radio email whilst at sea and away from the mobile (cell) phone networks.

  • To get weather info at sea either from the internet, Sailmail or Winlink using email.

Send an email to with no subject. In the message body
"get" The above example "get" line of text will get you the text from the Australian Bureau of Meteorology for Morton Bay. No quotes in the message body. After sending the email, wait five minutes and check your incoming mail and there it is. What is happening here is the email is sent to saildocs, a computer at saildocs looks on the internet for the web link you have sent then "scrapes" the web page of text and sends this text back to you. No images, just text. So, any email to saildocs with a valid web link (address) will be "scraped" and sent back to you. Try the following:- get and you will get the text only from my home page. Saildocs is provided without charge thanks to the support of Sailmail, a membership-owned radio email service for cruising sailors which operates a seamless network of 13 stations world-wide (including five covering the Caribbean and Atlantic).

  • To receive Weather Fax's, read on.

Weather Fax is available world wide, another free service which can be downloaded either via your Pactor modem connected to your computer and HF SSB radio transceiver or directly from the HF SSB radio receiver or transceiver's audio output into the microphone input of your computer. Free software can be downloaded from the web. One such site is JVcomm32, which has a pretty good product or Airmail's GetFax program.



  • Grib Files, what are they and how do you get them?

They are weather files that may be viewed or overlaid on navigation programs such as OpenCPN and Maxsea. They can display wind speed and direction, wave heights, barometric pressure and sea temperature and Rain. To get them, send an email to with no subject and the following:-
send GFS:14S,19S,143E,149E|1,1|0,24..144|PRMSL,WIND,WAVES
Which is asking for a grib file in the grid of 14S-19S 143E-149E| with a granularity of 1,1| 0,24..144 is the hours requested from when requested, so, 0,24 = prediction every 24 hours and ..144 = every day (24hours) for 144 hours = 6 days| PRMSL is pressure WIND is wind speed and direction, WAVES is for wave height. If you add to the end, RAIN, you get rain as well.
send GFS:14S,19S,143E,149E|1,1|0,12..168|PRMSL,WIND,WAVES,RAIN
Which is asking for a grib file in the grid of 14S-19S 143E-149E| with a granularity of 1,1| 0,12..168 is the hours requested from when requested, so, 0,12 = prediction every 12 hours and ..168 = every day (24hours) for 168 hours = 7 days| PRMSL is pressure WIND is wind speed and direction, WAVES is for wave height and RAIN, you get rain prediction as well.
Bear in mind, the more info you request, the bigger the grib file. You can view these files with a free program called ViewFax, available from the Airmail page. If all this is too hard then download the Airmail program and goto the "Grib Request Window" and it formats and addresses a message for you, you can then cut and paste this information into your own email program and send it off. The Airmail program is available from here.
There is another free program available to read grib files and this site also allows you to request and download grib files simply and easily. You need to register for this site but it is free. is the site. It is a great site worth a look at. It also allows you read downloaded grib files when you are not on the internet and you don't have Airmail or a chart program to display them.

  • Bob McDavitt's Weathergrams.

You can subscribe for free to Bob McDavitt. It comes out every Sunday and gives a breakdown on what's happening in the South Pacific including the Solomons, Vanuatu, Fiji, the Cooks, New Cal and NZ.

You can subscribe by sending an email to:-

Message Body: Subscribe nz.wgrm


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