mesoscale convective complex

A mesoscale convective complex (MCC) is a large, organized group of thunderstorms that cover an area roughly the size of a small state, usually between 100 to 300 miles across. It forms when individual thunderstorms merge and sustain each other over several hours, often producing heavy rain, strong winds, and sometimes hail or flooding. MCCs typically develop in warm, moist conditions and can impact weather over wide regions, especially in late summer or early fall. They are important for weather forecasting because they can bring significant weather events affecting large populations.