Which code represents overcast conditions in a METAR report?

In a METAR report, the code that indicates overcast conditions is OVC. This abbreviation specifically denotes that the sky is covered by clouds at a significant level, meaning that the cloud layer is thick enough to obscure the sun completely, resulting in overcast conditions.

Understanding the other terms can help clarify why OVC is the correct choice. For example, CLR stands for clear skies, indicating no significant cloud cover. FEW refers to a few clouds, which means there are some clouds, but they do not cover a large portion of the sky and the sky is still primarily clear. BKN, or broken clouds, signifies that there are clouds covering between 5/8 and 7/8 of the sky, which is not as dense as overcast but still indicates a significant amount of cloud cover. Therefore, OVC is the term that best describes complete cloud cover, distinguishing it clearly from other levels of cloud coverage.