https://phys.org/news/2018-09-nasa-large-powerful-hurricane-florence.html

Infrared and Microwave Satellite Images Reveal

Early on Sept. 13, NASA's Aqua satellite's infrared data showed the clouds in the southern quadrant of Hurricane Florence appeared warmer than storms throughout the rest of Florence. That means that the cloud tops are lower in the atmosphere, and the storms are not as powerful. That's because vertical wind shear, the change of speed and direction of winds with altitude was buffeting the southern side of Florence and preventing the development of higher, stronger thunderstorms in that part of the storm.