POSTED: 1:55 pm EDT August 14, 2006
UPDATED: 2:00 pm EDT August 14, 2006

MIAMI -- Every hurricane season, clusters of showers and thunderstorms roll off the coast of Africa and head over the Atlantic toward America. Most of the 60 or so tropical waves never do any harm. But about 10 eventually grow into tropical storms or monster hurricanes like Katrina and Andrew.

Researchers still don't know exactly what makes some waves stay weak and others strengthen into hurricanes. So starting this week, NASA and the National Oceanic and Atmospheric Administration will study these tropical systems from their breeding ground in Africa west toward the U.S to try to find out.

Birth Of Hurricanes Studied