Which element of a METAR/SPECI report does NOT use imperial measurements?

In a METAR/SPECI report, the temperature is typically reported in degrees Celsius, which is part of the metric system, rather than in Fahrenheit, which is an imperial measurement. This distinguishes temperature from other elements in the report, such as visibility, wind speed, and pressure, which can utilize imperial units.

For example, visibility is often measured in statute miles, wind speed can be expressed in knots (which can be converted to miles per hour but is often treated as a separate standard), and pressure is commonly reported in inches of mercury, which aligns with traditional imperial measurements. Therefore, the correct understanding is that temperature is the only element represented in metric units within a METAR/SPECI report.