Range criteria may take the place of the criteria.

• A. Aviation Selected Special Weather Report (SPECI)
• B. Local
• C. SPECI
• D. METAR

Answer: (C)

The main idea is when to issue a special weather report. Special weather reports are issued not on a routine schedule, but whenever weather changes are significant enough to impact flight operations. Range criteria define the thresholds for what counts as “significant.” If the observed conditions cross those ranges (for example, a notable drop in visibility or a drop in ceiling to a lower flight category), a SPECI is issued to alert aviation users to the new, potentially hazardous conditions. This is why SPECI is the best answer: it represents the special report used to communicate significant changes, as opposed to routine METARs or other non-aviation report terms. METAR is the regular observation, not the triggered alert, and Local isn’t a standard aviation weather report. A variation like Aviation Selected SPECI isn’t the standard designation in this context.