What does RMK refer to in a METAR report?

In a METAR report, RMK stands for "Remarks." This section provides additional information that may not be included in the standard elements of the METAR. Remarks can give insights into various conditions or observations, such as specific weather phenomena, runway conditions, or other pertinent notes that could affect flight operations. The ability to include remarks enhances the utility of METAR reports by allowing meteorologists and aviation personnel to convey information that is beyond the basic weather data formatted in the report. This context is crucial for pilots and air traffic controllers to make informed decisions regarding flight safety and navigation.