Which code corresponds with patches of fog?

The code that corresponds with patches of fog is indeed BR. This designation comes from aviation weather reporting conventions, specifically the METAR format, which is used to convey information about weather conditions at airports.

Patches of fog, classified as visibility-reducing phenomena, are commonly represented by the abbreviation BR. This specifies mist or fog that doesn't meet the criteria for denser fog, but still indicates a reduction in visibility due to tiny water droplets suspended in the air. It usually results in a visibility of less than 6 statute miles but more than 1 mile, distinguishing it from more severe fog conditions.

Understanding this abbreviation is vital for pilots as it informs them about potentially challenging visibility conditions that can affect flight operations. Such awareness allows for better flight planning and increased safety during navigation in areas where visibility might be compromised due to weather effects.