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
Southeast Flood Risk Lingers Near Stalled Front

Southeast Flood Risk Lingers Near Stalled Front

A stalled boundary over the Carolinas will ke

24 Jul 2026 12:35 PM
Severe Chances Return for the Midwest

Severe Chances Return for the Midwest

The upcoming stretch of hot temperatures will

24 Jul 2026 12:25 PM
Tropics: Bertha Dissipates, Fausto Heads to Hawaii

Tropics: Bertha Dissipates, Fausto Heads to Hawaii

BerthaBertha has dissipated after moving inla

24 Jul 2026 11:50 AM
Hot & Smoky w/ a Chance of Lightning

Hot & Smoky w/ a Chance of Lightning

Conditions have been really dry out west. We'

24 Jul 2026 11:15 AM
Very Hot Temperatures For the Western and Central United States

Very Hot Temperatures For the Western and Central United States

Are you over the summer heat yet? Well, more

24 Jul 2026 9:20 AM
Another Round of Storms Targets the Northeast

Another Round of Storms Targets the Northeast

Tuesday brought severe weather again across p

23 Jul 2026 1:15 AM
Another Round of Severe Weather for the Upper Midwest and Great Lakes

Another Round of Severe Weather for the Upper Midwest and Great Lakes

The upper-level low train continues to keep t

21 Jul 2026 1:45 AM