albatross
An understandable question - Low Visibility Procedure, an IR-Ops term (although Breakthesilence does not identify if he is in an area governed by IR-Ops) that it appears is being referred to based on the context of the original post. Here in FAA land, since they are never shy about making things as complex and confusing as possible the term used is LVO/SMGCS - Low Visibility Operations / Surface Movement Guidance and Control Systems. All well above my pay grade in all the professions I practice so my simple understanding is that these are added safety practices that allow surface movement in poor visibility conditions, departures for those that can meet the departure requirements, and landings which are limited primarily to aircraft that can perform Cat III approaches but if things are marginal you might squeak in a Cat II capable aircraft.
Or, maybe what a dyslexic person would call an LPV (Localizer Performance with Vertical Guidance) approach - OK just kidding, but have to give a nod to my fellow dyslexics. Watch out for clearance to land rwy 31 (or is that ...)