A prevailing visibility of 1/2 mile is typically reported as what?

A prevailing visibility of 1/2 mile is reported as 0.5sm because the "sm" stands for "statute miles," which is the unit of measure used for visibility in aviation meteorology. To express a distance of half a mile in statute miles, it must be represented as a decimal, leading to the correct notation of 0.5sm. This format is standard in aviation weather reporting to ensure clarity and precision, especially when communicating important visibility information to pilots and aviation personnel.