A mesoscale convective system (MCS) is a linear complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms, and normally persists for several hours or more.
On November 11, 1940, a rapidly deepening low-pressure system moved northeast from Kansas City, MO northeast through the Upper Mississippi River Valley and into the Upper Great Lakes. This low-pressure area produced the lowest pressure reading ever recorded up to this time at Charles City, IA (28.92 inches), La Crosse, WI (28.72 inches), and Duluth, […]