How do superstorms begin?

Answer 1

There is no particular way in which they form, as "superstorm" is not a scientific term. It has been used by the media to describe a number of powerful storms of different types.

The most recent case was with Hurricane Sandy, which some of the media referred to as "Superstorm Sandy." This came about when Sandy traveled northward and combined with a cold front as it transitioned into a post-tropical cyclone.

Another system was the large extratropical cyclone that hit the United States in March of 1993 which has been called the "Storm of the Century" and the "1993 Superstorm." This system developed as an arctic high pressures system brought a blast of cold air to North America. The resulting temperature contrasts caused a low pressure system over Mexico to intensify, as extratropical cyclones are powered by temperature contrasts. The storm was primarily a blizzard, but it also produced severe thunderstorms and tornadoes.

Another system that some have called a superstorm was the unnamed hurricane in October of 1991 that is most widely known as "the Perfect Storm" It developed when an extratropical cyclone absorbed the remnants of Hurricane Grace while at the same time interacting with an arctic air mass, causing the storm to greatly intensify. The storm later acquired tropical characteristics and became a full-fledged hurricane.

Another system that could be considered a superstorm was the derecho which hit the U.S. in May of 2009. This storm, called a "super derecho", a "tornadocane," and a "landphoon" by various media developed as a cluster of thunderstorms that organized and became extremely intense, producing wind gusts to over 100 mph, and numerous tornadoes.