What You Need to Know About the 5 Hurricane Category Rankings
Each Category comes with its own potential damage and forecasted sustained winds.
This NASA satellite image shows Hurricane Lane as a powerful category 4, at 10:45 a.m. (HST) on August 21, 2018.
Photo: Courtesy of NASA
With Hurricane Lane forecasted to reach the Islands this week, weather officials say it is a Category 4 hurricane, with wind gusts of 155 mph. That sounds really serious (and scary), but what does that actually mean for us regular folk?
Weather officials use a system that ranks hurricanes from 1 to 5 based on sustained wind speed. Under the Saffir-Simpson Hurricane Wind Scale (developed by wind engineer Herb Saffir and meteorologist Bob Simpson, who established a weather observatory at Mauna Loa), each is categorized from very dangerous to catastrophic.
We break down each category in more detail (based on information from the National Hurricane Center), and take a look back at a few notable hurricanes that hit Hawai‘i.
Category 1 and 2 storms are not considered major hurricanes but are still dangerous. The National Hurricane Center describes Category 1 hurricanes as having very dangerous winds and causing some damage. Hurricane ‘Iwa, a Category 1 storm, hit the Islands in November 1982, resulting in up to $250 million in property damage on Kaua‘i and one death. It was the most damaging hurricane to hit the state at the time until Hurricane ‘Iniki struck 10 years later.
Sustained winds: 74 to 95 mph
Potential damage: Large branches of trees will snap and some shallowly rooted trees may topple. The roof, shingles, vinyl sidings and gutters of some homes may be damaged. Power outages to last for a few to several days due to downed or damaged power lines and poles.
Similar in damage level to Category 1 storms, Category 2 hurricanes carry extremely dangerous winds that will cause extensive damage.
Sustained winds: 96 to 110 mph
Potential damage: Roof and sidings of homes could be damaged. Many shallowly rooted trees will snap or uproot, blocking many roads. A near complete or total power loss is expected for several days to weeks.
The #Himawari satellite captured dual typhoons #Soulik and #Cimaron spinning near #Japan and #Korea in the Pacific early this morning. More satellite storm imagery: https://t.co/P1F11zXUHI pic.twitter.com/IUuXZlkTCz— NOAA Satellites (@NOAASatellites) August 22, 2018
Category 3, 4 and 5 hurricanes are considered major storms and will cause extensive to catastrophic damage. Category 3 in particular will cause devastating damage, according to the National Hurricane Center.
Sustained winds: 111 to 129 mph
Potential damage: The roof decking and gable ends of homes might snap off, resulting in major damage. Many trees will either uproot or snap. Total loss of electricity and water for several days to weeks after the storm passes.
Considered the most devastating hurricane to hit the Islands, ‘Iniki, a Category 4 storm, caused six deaths and $3 billion in damage in September 1992. Kaua‘i was hit with widespread flooding and wind gusts of 145 mph. It took four months to restore all power, water and phone services. In the aftermath of ‘Iniki, the National Weather Service increased its forecast efforts by installing a satellite above the eastern Pacific, providing a direct view of Hawai‘i.
Hurricane Iselle, initially a Category 4, weakened and hit the Islands as a tropical storm in 2014, bringing heavy rain, flooding and some damage.
Sustained winds: 130 to 156 mph
Potential damage: Homes will be severely damaged, including loss of most of the roof and some exterior walls. Most trees and power poles will be down, isolating residential areas from each other. Power outages will last weeks to months. Most of the area will not be inhabitable for weeks or months.
To date the United States has been hit by only three Category 5 hurricanes: the 1935 Labor Day hurricane that devastated the Florida Keys and killed 600 people, Hurricane Camille that caused 256 deaths on the Mississippi coast in 1969, and Hurricane Andrew in South Florida, which left 43 dead in 1992. (If you’re wondering about Hurricane Katrina in 2005, it reached Category 5 status but weakened and struck the coast as a Category 3.)
Forecasters made the call late Tuesday that Hurricane Lane reached Category 5 status, but the storm weakened to a Category 4 this morning.
Sustained winds: 157 mph or higher
Potential damage: The majority of framed homes will be destroyed, with roofs and walls collapsing. Many trees and power poles will be down, isolating residential areas. Power outages are expected for weeks to months. Most of the area will not be inhabitable for weeks or months.