What does the '2 group' in a METAR report indicate?

The '2 group' in a METAR report refers specifically to the minimum temperature recorded in the last 6 hours. This group is denoted by a number followed by a "M" for temperatures below zero. For example, if the group reads "M05", it indicates a minimum temperature of -5 degrees Celsius.

In METAR reports, temperature information is crucial for understanding current weather conditions; hence, the minimum temperature helps various sectors including aviation, agriculture, and environmental monitoring. In contrast, maximum temperature readings and longer time frames such as 24 hours are not represented in this specific group, which is why other options like maximum temperatures do not apply here. Understanding such details helps meteorologists and pilots make informed decisions based on recent weather patterns.