What is the criteria for reporting the end of a thunderstorm?

The correct criteria for reporting the end of a thunderstorm is based on the occurrence of thunder or lightning. Specifically, the end of a thunderstorm is reported 15 minutes after the last occurrence of thunder or lightning. This is significant because both thunder and lightning are direct indicators of an active thunderstorm; they provide a reliable means of determining whether the storm is still affecting the area.

The timing is essential as it allows for a period of safety after the last audible indications of the storm, ensuring that any lingering hazards, such as potential flash flooding or residual electrical activity, have passed.

Other options do not align with criteria used for storm reporting. For instance, focusing solely on lightning or rain cessation could lead to inaccurately assessing the safety status of the storm. The dissipating of storm clouds alone can be misleading since some storms can continue to pose risks even if the heavier precipitation and activity have apparently ended. Thus, monitoring the sound of thunder or sighting of lightning remains the most effective method for declaring the end of a thunderstorm.