This image of ocean temperatures on June 30, 2009, shows why storms that form in the early part of the Atlantic hurricane season tend to happen in the Gulf of Mexico and Caribbean Sea.
Warm sea surface temperatures help fuel hurricanes, and in 2006, those temperatures were cooler than expected. Why the difference between 2005 and 2006? William Lau of NASA Goddard Space Flight Center and Kyu-Myong Kim of University of Maryland-Baltimore County think the answer comes from the Sahara, namely dust.