Hurricanes form when warm ocean water, moist air, and rotating winds come together in the tropics. Here’s a concise explanation of the key steps and conditions.

• Warm water and humid air fuel the storm
  • Ocean surfaces at roughly 80°F (27°C) or warmer evaporate more water into the air, creating a large reservoir of heat and moisture that powers developing storms. This energy release through condensation warms the air and drives vigorous upward motion. [NOAA NOAA source summary]

• Formation starts as a tropical disturbance
  • A tropical wave or area of low pressure over warm seas begins to organize thunderstorms. As the warm, moist air rises, more air rushes in at lower levels, creating a feedback loop that intensifies the system. [NOAA NOAA source summary]

• Rotation and organization develop
  • The Coriolis effect in the Northern Hemisphere causes the system to begin rotating, organizing the convection into a spiral around a relatively calm core. This organized circulation is a hallmark of a developing tropical cyclone. [UCAR/NOAA educational sources]

• Classification threshold
  • When sustained winds reach about 74 mph (119 km/h), the system is classified as a hurricane in the Atlantic and Northeast Pacific (the term varies by region, e.g., tropical cyclone or cyclone elsewhere). [NOAA/UCAR sources]

• Anatomy and structure
  • A hurricane typically features an eye (a relatively calm center), surrounded by an eye wall with the strongest winds and intense thunderstorms. The storm draws energy from the ocean as long as warm water and atmospheric conditions remain favorable. [NOAA weather training resources]

• Why they don’t always form
  • Even with warm seas and moisture, many disturbances fail to become hurricanes due to factors like wind shear, dry air, or insufficient time over warm water to organize. Conditions must remain favorable for days for a hurricane to develop. [NOAA/NOAA UCAR explanations]

• What happens after formation
  • Hurricanes derive their energy from warm ocean water. If they move over land or move into cooler waters, their supply of heat/moisture is cut off and they weaken, though coastal areas can still experience heavy rain, storm surge, and strong winds. [NOAA educational materials]

If you’d like, I can tailor this explanation to a specific region (e.g., Atlantic, Pacific) or provide a simple diagrammatic flow of the formation stages.