What does "BECMG" in a TAF report signify?

In a TAF (Terminal Aerodrome Forecast) report, "BECMG" is an abbreviation that signifies "becoming." It is used to indicate a change in the expected weather conditions over a specified period. The term is employed when the forecast predicts that the weather will evolve from one state to another, which might involve transitions in visibility, wind conditions, or weather phenomena.

The phrasing typically outlines how the weather is expected to develop or change, emphasizing that an alteration is anticipated but not detailing what specifically those changes will be. For pilots and flight planners, understanding that "BECMG" indicates a transition is crucial for safe flight operations and planning, as it alerts them to remain vigilant about changing conditions.

The other options do not accurately capture the meaning of "BECMG." While "becoming worse" or "becoming good" could describe certain changes in weather, "BECMG" itself is neutral and simply denotes a transition without indicating the direction of that change. "Breaking," in this context, is also not applicable to the abbreviation. Thus, "becoming" is the correct interpretation in the context of TAF reports.