In a SPECI report, when is the time of the Date/Time group recorded?

In a SPECI report, the time of the Date/Time group is recorded when the specific criterion for a SPECI is met or noted. This means that the observation captures the moment when a significant change in weather or conditions occurs, which triggers the need for a special weather report. The purpose of a SPECI report is to provide updated information on conditions that may affect flight operations, so accurately timestamping when the change is recognized ensures that pilots and air traffic control have the most current and relevant data.

When the criteria are met, it indicates a noteworthy weather event, such as significant changes in visibility, wind, or precipitation. This timestamp is crucial for understanding current conditions and making timely operational decisions. This adherence to timing when the change is observed distinguishes the SPECI from regular METAR reports, where the timing might follow a different structure related to routine observations.