What information follows "VV" when reporting total obscuration in sky conditions?

When reporting total obscuration in sky conditions, "VV" specifically indicates a vertical visibility measurement through an obscuring medium, typically associated with fog or heavy precipitation. Following "VV," the information that follows is the height of the indefinite ceiling, expressed in hundreds of feet. This denotes how far one can see vertically through the obscuring phenomenon.

Understanding this is crucial for pilots and air traffic personnel, as knowing the height of the indefinite ceiling helps them to gauge potential visibility and assist in flight planning. It aids in determining whether conditions are suitable for visual flight rules (VFR) or if instrument flight rules (IFR) conditions prevail, which would require navigation by instruments due to low visibility.

The other options do not follow "VV" in this context. Describing cloud types is more relevant in general sky condition reporting rather than specific to total obscuration. Historical data of visibility trends and forecasts for the next hour, while useful in different contexts, are not standard practices in immediate sky condition reporting that uses "VV."