I've had a lot of people ask me why did Gustav not strengthen, so I figured I would share my insight. Below are some notes from my meteorology notebook.
The short answer is tied to three main factors:
1) Dry air filtered into the bottom of the system;
2) Wind shear kept the eye wall from redeveloping and tightly wrapping the storm;
3) Speed also was a major factor. Ever since the storm left Cuba, it cruised along at 15-20 mph. Even though it moved over 90 degree water (which typically helps hurricanes strengthen) Gustav's high velocity kept it from developing into an even more deadly hurricane.
It's also worth noting that New Orleans itself was spared the brunt of the storm due to a last minute shift to the west. If it had not made this turn, the damage would have been much worse.
While New Orleans missed a major storm, we now have Hannah and Ike in the Atlantic. Both storms will impact the eastern United States this week. Busy times ahead.
Jeff Ranieri, NBC meteorologist.