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Equipment required to receive marine weather forecasts and warnings on board a yacht or motorboat. Weather itself is complicated and so are the current systems for delivering weather information. As I see it the various possible systems are listed below -

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Used for communication of weather and other Marine Safety Information from MRCCs. Range is limited by line of sight. The signal is prone to being blocked by high ground or large structures.

VHF weather broadcasts are normally of inshore waters forecasts but may also include some forecasts for open sea areas. See another page for VHF schedules.

Broadcasts are usually in the local language although some countries have English language versions. There is often little problem in learning the basic terms and these can be found in the RYA weather forecast booklet, G5. For thos who worry about the language, I have a comprehensive list of French weather words on another page.


This long wave radio system is a component of the GMDSS. It is designed for use from the fairway buoy out to about 200 NM although it can often be received further out. See other pages for NAVTEX schedules, NAVTEX details and Reception problems.

NAVTEX usually provides twice a day, 24 hour forecasts with a brief outlook that should be for a further 24 hours. It provides forecasts for offshore *sea) areas

The international 518 kHz frequency broadcasts are always available in English. The secondary frequency of 490 kHz is used for national purposes. The UK, exceptionally at present, uses a national NAVTEX frequency of 490 kHz for inshore waters forecasts.


This is, effectively, the open ocean version of NAVTEX. Transmissions are from geostationary satellites. This, in effect, limit reception to latitudes equator-wards of about 60 – 65 degrees. Although rather expensive, Inmarsat-C can also be used to send (slowly) text messages and emails.

The weather information provided is a 24 hour forecast and a brief outlook for a further 24 – 36 hours. Areas covered are for the open ocean, eg the UK North Atlantic bulletin. The French term is "bulletins au grand large".


RTTY is a HF/SSB (Single Side Band) long range radio system used by the German weather service, DWD and the US Coast Guard as SITOR (Simplex Teletype over Radio). The technology is old and speeds are slow. For more, see my Radio Teletype Page.

SITOR has been called a long range form of NAVTEX. It is used by the USCG to broadcast navigation and weather information over the Atlantic and Pacific oceans. It is used over the polar regions which are not covered by Inmarsat-C.

Radio Facsimile

This is another old system that uses HF/SSB to broadcast weather charts. Either a computer and software is needed or a dedicated receiver/decoder. Transmissions are very slow and it can take 20 minutes to receive a chart. Radio fax schedules can be found from links on my GMDSS page.

Although it can be useful, and I have found it so, it has been largely superseded by alternative delivery systems and techniques. These include Internet web pages and the use of email and GRIB coded products.

National and Local Radio

Use of national radio very obviously depends upon ability to comprehend the language. The BBC shipping forecast is, arguably, one of the most useful simply because it is updated on a 6-hourly basis. The German Public service radio broadcasts in German are exceptionally clear and easy to understand.

Local radio, in the UK at least, is a variable feast. Much depends on the interest of the local station controller and staff. Schedules and content can vary at no or short notice. Not to be relied upon.

Telephone and Data networks

Use of conventional telephone has largely been superseded by 3G data networks accessed by PCs and Tablets or Smartphones. These anable reception of text forecasts, GRIB files and Internet access generally.

Otherwise, the main use of telephones will be to use “Speak to a forecaster” services. Recorded voice and SMS services are virtually non-existent in the UK and will become rare generally.

So, what do I need?

For all sailors, VHF and NAVTEX should be regarded as necessary because these are the systems put in place under the GMDSS for the dissemination of MSI.

For blue water sailors, one or both of Inmarsat and HF/SSB radio will enable reception of GMDSS services. Pgaes on RTTY and RadioFax might help.

See also the page on Radio Communications.

Increasingly, the Internet will be used as a means of accessing the same information. Equipment used will depend on circumstances. Ashore or near the coast terrestrial communications using Smartphone, Tablet or laptop computer are required. Sometimes, With no 3G or WiFi access, it may be necessary to use a telephone to laptop connection to receive email services.

When out of range, then either a satellite phone, such as Iridium, Inmarsat, or HF/SSB radio plus modem will enable email services to be used.

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