Local Notice to Mariners (LNM) (LNM)

An official notice providing navigationally relevant changes or hazards for a defined local area.

A harbour, coastguard, hydrographic or other competent authority may issue an LNM covering works, buoyage, depths, closures, events, hazards or operating restrictions. The name, publication schedule, geographic scope and legal effect vary between countries and authorities.

Some information is temporary while other changes may later be incorporated into charts or publications. Mariners should use the current official issue for the intended area, note cancellation or supersession, and distinguish local notices from national Notices to Mariners and radio navigational warnings.