How are significant changes in weather conditions indicated in a TAF?

Significant changes in weather conditions within a Terminal Aerodrome Forecast (TAF) are indicated using specific terms that signal anticipated shifts in weather phenomena. The correct choice includes terms like "TEMPO" and "BECMG," which serve distinct purposes in the forecast.

"BECMG" is used to denote a gradual change in weather conditions over a specified period, such as a transition from one weather state to another, allowing forecasters to convey information about expected variations in visibility, cloud cover, wind, or other meteorological elements.

On the other hand, "TEMPO" indicates temporary fluctuations or weather phenomena that are expected to occur for a short period within the forecast timeframe, emphasizing that these changes will be transient in nature.

Understanding these indicators is essential for pilots and aviation personnel as they prepare for potential variations in operational weather primarily affecting takeoffs and landings. The other options do not represent standard terminologies used in TAFs, and thus do not effectively communicate such significant changes in weather conditions.