It’s Hurricane Season; How Hurricanes Lead to Tornadoes

At RemainSafe, we know storms. It’s no secret that hurricane season starts in June and is usually active until November in the United States. While we do not recommend sheltering from hurricanes in designated tornado shelters due to the high risk of flooding in low-lying areas, it is important to understand that hurricane side effects can lead to devastating tornadoes. Chris Mulcahy of WCNC Charlotte says “The worst tornado outbreak from a hurricane came in 2004 from Ivan, which produced 120 tornadoes across 9 states over 3 days.”

Why Tornadoes Spawned by Hurricanes are Particularly Dangerous

According to the NOAA National Weather Service, more than half of the hurricanes that hit the U.S. spawn one or more tornadoes in the impacted area. The same WCNC Charlotte article indicated, that anywhere between 50 to 200 miles from the center of a hurricane can be in danger of impact by hurricane-spawned tornadoes. It is vital that residents in locations known to be tornado-prone, or within close range of the coast be alert to any hurricanes near their area.

Hurricane-force winds, sometimes up to 50-60mph according to WRAL Raleigh, can travel further inland than one might expect. The National Weather Service states that these winds can travel 150 miles inland. As soon as a hurricane leaves the coast, tornadoes are likely to form on the front-right quadrant of the storm cell. Though tornadoes are dangerous no matter what reason they form, tornadoes spawned by hurricanes can emerge and strike faster, sometimes in only a few minutes according to meteorologist Elizabeth Gardner, of WRAL Raleigh.

What is the Science behind Tornadoes Spawned by Hurricanes?

How do hurricanes begin in the first place? How do they form deadly tornadoes? The main factor that leads to tornado formation from hurricanes is a change in friction at the bottom of a storm cell. Mulcahy shares, that since hurricanes start to develop over oceans that have low friction on the surface, hurricanes will not spawn tornadoes while over open water. Once hurricanes reach land, though, the high-speed winds can form spirals. This is caused by wind speeds slowed by the earth at the bottom of the storm cell while the wind speed remains the same at the top, causing wind paths to turn. The process of rapid wind velocity change creates a twisting force called “wind shear.” Wind shear is responsible for tornadoes resulting from hurricanes. According to Mulcahy, “This all happens in the outer bands of the tropical cyclone which are located 50 to 200 miles plus from the storm’s center. These bands of thunderstorms thrive due to the warm moist air being pumped into them by the storm which is ideal for tornadoes.”

How Can a Storm Shelter Protect You?

Though using a storm shelter for protection during a hurricane or a tropical storm is not recommended due to the risk of flooding, the resulting tornadoes can be very dangerous. Since tornadoes form over land and often in areas far from the coast, and when formed from hurricanes quickly, it is always best to prepare for meteorological surprises and have shelter to protect yourself.

RemainSafe manufactures above and below-ground storm shelters for both residential and commercial use. To ensure your safety, we 3rd party engineer, wind and impact test our storm shelters to ensure FEMA compliance and other EMA guidelines. To learn more about RemainSafe and how we can keep you protected in the face of severe winds, visit our website or contact us today.