Spiral Rainbands
A view of Hurricane Ike's rain bands from space
The storm’s outer rainbands (often with hurricane or tropical storm-force winds) can extend a few hundred miles from the center. These dense bands of thunderstorms, which spiral slowly counterclockwise, range in width from a few miles to tens of miles and can extend hundreds of miles from the center. Typical hurricanes are about 300 miles (about 500 km) wide, but, as seen in the images below, there is considerable variation. Hurricane Floyd’s rainbands (1999) stretched over 400 miles (about 600 km). However, Hurricane Andrew’s (1992) rainbands reached only 100 miles (160 km) out from the eye. Hurricane rainbands are also the favored location for hurricane-spawned tornadoes to occur.
The spiral rainbands of Hurricane Floyd (left, 1999) versus the more compact Hurricane Andrew (right, 1992)