In the UK, the Maritime and Coastguard Agency (MCA) is responsible for the provision of Maritime Safety Information (MSI) to ships at sea, which includes both weather and navigational warnings.
A full Maritime Safety Information service is available on NAVTEX (518 and 490 kHz).
Solent & Portland Maritime Rescue Coordination Centre (MRCC) broadcast on: Channels VHF 23, VHF 84, and VHF 86.
MSI is broadcast in local time such that the 'clock time' that the broadcasts will be received at will remain the same throughout the year:
0130 - B 0430 - C 0730 - A 1030 - C
1330 - B 1630 - C 1930 - A 2230 - C
Routine A - Full Maritime Safety Information broadcast, including new inshore forecast and outlook, gale warnings, shipping forecast, navigation warnings (WZ), SUBFACTS and GUNFACTS where appropriate, three day fisherman's forecast when and where appropriate.
Routine B - New inshore forecast plus previous outlook, gale warnings.
Routine C - Repetition of inshore forecast and gale warnings as per previous Routine A or B broadcast plus new strong wind warning (SWW).