An unscheduled observation completed and transmitted when any of the special criteria are observed, and will include all data elements in a METAR plus additional remarks, is called what?

• A. Aviation Routine Weather Report (METAR)
• B. Aviation Selected Local Weather Report (LOCAL)
• C. 3-hourly observations
• D. Aviation Selected Special Weather Report (SPECI)

Answer: (D)

A SPECI is an unscheduled Aviation weather report issued when any of the special criteria indicate a significant change in weather conditions. It contains all the data elements of a METAR, plus additional remarks describing the noteworthy conditions. This differs from a routine METAR, which is issued on a regular hourly schedule, and from other report types that follow planned timing or local criteria. The trigger for a SPECI is a notable change in factors that could affect flight operations, such as evolving visibility, ceiling, wind, or notable weather phenomena, prompting immediate dissemination to pilots and operations.