In the Atlantic Ocean, the Main Development Region (MDR) refers to the area where most powerful tropical storms and hurricanes form, especially during the peak months of hurricane season — typically from mid-August to late September.

This region spans from the west coast of Africa to the Caribbean Sea, generally bounded between 10 and 20 degrees North latitude and stretching from West Africa to the Lesser Antilles.

The MDR is critical because it serves as the "breeding ground" for long-track storms that often grow into major hurricanes. Warm sea surface temperatures, low vertical wind shear and abundant moisture in the mid- to lower atmosphere create ideal conditions for tropical cyclogenesis in this zone.

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African easterly waves, which emerge off the coast of Senegal and Guinea, frequently act as the initial disturbances that, under the right conditions, develop into tropical depressions and then hurricanes.

What happens in the MDR can often dictate the tone of an entire hurricane season.

In years with warmer-than-average ocean temperatures and favorable atmospheric patterns, the MDR can become especially active, leading to more frequent and intense storms. Conversely, Saharan dust outbreaks or strong wind shear can suppress development, even if sea temperatures are warm.

Monitoring this region closely gives forecasters the best early insight into how a storm season might evolve — and which systems could pose threats to the Caribbean, the Gulf and the southeastern U.S. coastline.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.