What does "P" signify in regards to visibility in a METAR?

In a METAR report, "P" signifies that the visibility is greater than 10 statute miles. This designation indicates that pilots can expect clear visibility conditions, which is crucial for safe flight operations. The use of "P" is a standard abbreviation used in aviation meteorology to communicate visibility that exceeds the specified threshold, ensuring that pilots and air traffic controllers are aware of favorable visual conditions.

Visibility measurements in METAR reports typically include specific numeric values, such as "6SM" for six statute miles. However, when visibility exceeds 10 statute miles, "P10SM" or simply "P" is used to denote this enhanced visibility status without needing to state the exact value. This information is vital for pilots during arrival and departure phases of flight, as it impacts approach procedures and overall navigation.

The other options pertain to different meteorological or operational conditions not related to visibility in METAR codes, making it important to recognize that the "P" specifically addresses visibility-related information.