Squall
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A squall is a sudden, sharp increase in wind speed lasting minutes, as opposed to a wind gust, which lasts for only seconds. They are usually associated with active weather, such as rain showers, thun
A shelf cloud such as this one can be a sign that a squall is imminent
A summer squall line in Southern Ontario, producing lightning and distant heavy rains.
Mesoscale convective system
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A mesoscale convective system is a complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms but smaller than extratropical cyclones, and normally persists fo
Squall
…forms of mesoscale meteorology, including simplistic isolated thunderstorms unrelated to advancing cold fronts, to the more complex daytime/nocturnal mesoscale convective system (MCS) and mesoscale convective complex (MCC), to squall line thunderstorms. The main driving force behind squall line creation is attributed to the…
A shelf cloud, such as this one, can be a sign that a squall is imminent. This is an example of a MCS.
Hurricane Catarina, a rare South Atlantic tropical cyclone viewed from the International Space Station on March 26, 2004