What is an MCS?

news image
Special Stories
8 Jun 2025 8:00 AM

MCS - A common summertime storm phenomenon, but what is it? MCS stands for Mesoscale Convective System, a term used to describe an organized cluster of thunderstorms that lasts for several hours and can span multiple states.

During the summer, MCSs often form overnight as individual afternoon thunderstorms merge into larger storm complexes. These systems are commonly linear in structure, forming squall lines that stretch for miles. The primary threats associated with MCSs include damaging winds and torrential rainfall, though hail and even tornadoes can also occur.

There are different types of MCSs:

  • MCC (Mesoscale Convective Complex): A large, circular, and long-lived cluster of storms.

  • Mesoscale Convective Vortex: A rarer form that can resemble a small hurricane.

  • Derecho: An especially destructive wind-driven MCS capable of causing widespread damage across hundreds of miles.

Understanding the risks associated with these systems is key. Always have multiple ways to receive weather alerts—especially at night, when many MCS events tend to occur.

All Weather News
More
Tropical Storm Moke Has Formed in the Pacific; Impacts to Hawaii Start Sunday

Tropical Storm Moke Has Formed in the Pacific; Impacts to Hawaii Start Sunday

TROPICAL STORM MOKEJust days after Hurricane

22 Aug 2026 10:00 AM
Severe Storms Continue to Ride Around Heat Dome

Severe Storms Continue to Ride Around Heat Dome

Several frontal systems will cross the countr

22 Aug 2026 10:00 AM
Heat, Some Humidity, and Storms Return to the Southwest

Heat, Some Humidity, and Storms Return to the Southwest

As we get through the work week, high pressur

22 Aug 2026 1:55 AM
Atlantic Tropics : Watching Several Areas, Strong Tropical Wave Next Week

Atlantic Tropics : Watching Several Areas, Strong Tropical Wave Next Week

El Niño has been smothering tropical waves in

22 Aug 2026 1:20 AM
Stifling Heat Holds Steady for Southern U.S.

Stifling Heat Holds Steady for Southern U.S.

A ridge of high pressure has dominated the so

21 Aug 2026 11:00 AM
Severe Storms and Heavy Rain Across the East Coast

Severe Storms and Heavy Rain Across the East Coast

A stormy end to the week is taking shape for

21 Aug 2026 10:00 AM
Front That Caused Flooding Heading East

Front That Caused Flooding Heading East

MIDWEST - After a week of flooding rains in t

18 Aug 2026 1:30 AM