The Saffir-Simpson Scale categorizes a hurricane based on its wind speed. Category 5 is the worst, while tropical storms and depressions generally cause less damage.
Less intense hurricanes are generally more common than "major" hurricanes, those that are Category 3 and above. In the map below you can see how many of these storms hit the continental US from 1950-2011, color-coded by category.
Tropical storms have wind speeds of 39-73 mph. Once a storm crosses this threshold, it gets a name.
Hurricane Dolly was Category 1 when it hit Texas in 2008.
next slide will load in 15 secondsSkip AdSkip AdCategory 1 hurricanes have wind speeds of 74-95 mph. They can damage the outside of homes, break large tree branches, and possibly knock down power lines, causing outages for several days.
Hurricane Ike was a Category 2 storm that also hit Texas in 2008. Its diameter reached 425 miles across at one point.
Category 2 hurricanes have wind speeds of 96-110 mph. Storms of this intensity can cause major damage to homes, uproot large trees, and power outages that last up to weeks are generally expected.
While a hurricane's category classifies how strong it is, this definition can't fully predict how devastating it might be. Superstorm Sandy hit Category 3, but by the time it made landfall in New York and New Jersey in 2012 it had weakened to a post-tropical cyclone.
Category 3 storms have wind speeds of 111-130 mph. But with Sandy, the storm surge did some of the worst damage. It reached nearly 8 feet in parts of the Jersey Shore and 6.5 feet around New York City. Its "superstorm" status was because it was so wide — up to 1,000 miles across.
next slide will load in 15 secondsSkip AdSkip AdHurricane Katrina was the most devastating storm ever to hit the United States. It killed 1,833 people and caused $108 billion in damage.
But Hurricane Katrina was technically a Category 3 when it made landfall in Louisiana in 2005.
Katrina had sustained wind speeds of 125 mph when it hit Louisiana, and by Aug. 31, 80% of New Orleans was flooded.
Hurricane Charley was a Category 4 storm when it made landfall in Florida in 2004. These storms have wind speeds of 131-155 mph, uprooting most trees and power lines.
With Category 4 storms, there could be power outages that can last weeks or even months. Hurricane Charley caused power outages for 130,000 people in Collier County, Florida.
next slide will load in 15 secondsSkip AdSkip AdHurricane Andrew was one of the strongest storms ever to make landfall in the US. It was a Category 5 hurricane when it hit Dade County, Florida in August 1992.
Category 5 storms have wind speeds greater than 156 mph, which can completely destroy most framed homes. Hurricane Andrew demolished 49,000 homes and damaged 108,000 more.
Category 5 hurricanes unquestionably cause power outages that can last weeks to months. Most of the area will be uninhabitable for that amount of time, too.