The new National Navtex forecasts are for waters up to 12 miles off shore for 16 stretches of coastline around the UK, and are broadcast twice a day.

There is also a three-day outlook and strong wind warnings – Force 6 or above over waters up to five miles offshore. These warnings are issued on receipt and repeated in following broadcasts until they expire.

The service operates from the three Navtex stations at Niton, Portpatrick and Cullercoats, at a frequency of 490 kHz.

Kim Fisher, Head of the Navigation Safety Branch at MCA said: “Navtex operating on the international frequency 518 kHz has been very successful over the past 15 years, but is now reaching saturation. The introduction of the national frequency 490 kHz provides new capacity for more information, particularly for smaller craft”.

Navtex receiving capability is part of the mandatory equipment required to be carried on certain vessels under the SOLAS Convention. Mariners in the UK can supplement their 518kHz Navtex with a 490kHz Navtex. Alternatively there are now systems on the market with the capability to receive both frequencies.