In the pilot report "KMOBUA/OV 15NW MOB 1340Z/SK OVC 025/045 OVC 090," what does it denote regarding significant cloud coverage?

In the report "KMOBUA/OV 15NW MOB 1340Z/SK OVC 025/045 OVC 090," the notation provides detailed information about cloud coverage, specifically the heights of overcast layers. The term "OVC" indicates overcast conditions, followed by the specified altitudes.

The correct interpretation is that there are three overcast layers at various heights. The first layer has a base at 2,500 feet and is referred to as the lower overcast layer. The second layer starts at 4,500 feet and extends to 9,000 feet, where it has a defined base and top, respectively. This detailed information means that both the base and top heights of these layers are explicitly identified, making it clear how many layers there are and where they are situated vertically.

This matches the correct answer, as it accurately conveys the layering and height specifics indicated in the pilot report, particularly noting the heights of the lower and second overcast layers. Such an understanding is essential for military and aviation operations, as it impacts flight planning and safety considerations.