Gusts reported in column 5 must have been observed within how many minutes prior to the actual time of observation?

The correct answer is ten minutes because aviation weather reports require that gusts noted in column five reflect conditions observed within a specific and standardized timeframe to ensure accuracy and relevancy. When determining gusts in relation to the time of observation, the ten-minute interval allows for a thorough assessment of short-term wind variations, providing pilots and meteorologists with pertinent data for flight safety and operational planning.

Using a ten-minute window ensures that the reported gusts truly reflect immediate weather conditions, rather than older data that may no longer be applicable, thereby enhancing the reliability of the weather observation for aviation activities.