What are the Ingredients Needed for a Tropical Storm or a Hurricane to Develop?

In order for a tropical storm to develop from an area of low pressure and strengthen into a hurricane, there are certain conditions that need to be met:

1. Ocean water temperatures of at least 80°F
2. Warm and moist atmosphere
3. Little wind shear (light winds aloft)
4. Elbow room (away from landmasses)

These same ingredients are necessary for an already existing storm to have a chance at maintaining itself or getting stronger.