Learn what the differences are between the different hurricane categories of 1 - 5.

Hurricane Michael: What damage can a Category 4 hurricane do?

Hurricane Michael was upgraded to a dangerous Category 4 storm overnight as it churned through the Gulf of Mexico to an expected landfall in the Florida Panhandle.

>> Read more trending news

What is a Category 4 hurricane and how dangerous is it? Here’s a look at how hurricanes form and how they are ranked.

First, what is a hurricane? A hurricane is a rotating low-pressure weather system. The system is born as an area of disturbed weather usually in the Atlantic Ocean, but can be in the Gulf of Mexico or the Caribbean Sea.

>> Hurricane safety: 15 tips that could save your life during a storm

If the conditions are right, the system organizes thunderstorms to create a sort of heat pump to draw fuel from the warm ocean waters. Tropical systems gain strength by drawing heat from the air and sending it upward to be released through condensation of water vapor in thunderstorms.

>> Get the latest live updates on Hurricane Michael in Florida here.

>> Get the latest live updates on Hurricane Michael in Georgia here. 

As these storms move across the warm ocean or in and around the Gulf of Mexico, they can grow stronger. 

When a system has sustained winds of 39 mph, it is classified as a tropical depression. When the winds reach 39 mph or higher, the depression becomes a tropical storm and is given a name.

At 74 mph, the system is a hurricane.

>> Hurricane safety: Here’s what to do if your car is swept away by water

What is the Saffir-Simpson scale and what does it have to do with hurricanes? The Saffir-Simpson scale categorizes hurricanes by wind strength. The tropical system is assigned a category depending on its wind speed. Here are the categories, the wind speeds and what those winds will likely do once the system makes landfall.
Category 1 – 74 to 95 mph: Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to the roof, shingles, vinyl siding, and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.
Category 2 – 96 to 110 mph: Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.
Category 3 – 111-129 mph: Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes. (Category 3 storms and above are considered major hurricanes).
Category 4 – 130-156 mph: Catastrophic damage will occur: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
Category 5 – 157 or higher: Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months. 

Here is a video that shows the increasing level of damage in each category.

A couple is silhouetted against the sunset at the St. Andrews Marina in Panama City, Fla., Tuesday, Oct. 9, 2018, ahead of Hurricane Michael. (Patti Blake/News Herald via AP)

This photo provided by April Sarver shows a flooded neighborhood boat dock in Fort Walton Beach, Fla., Tuesday, Oct. 9, 2018. A fast and furious Hurricane Michael sped toward the Florida Panhandle on Tuesday with 120 mph winds and a potential storm surge of 13 feet, giving tens of thousands of people precious little time to get out or board up. (April Sarver via AP)

Robert Sandousky gestures as he holds up some wire he plans on using to repair one of his fences from storm debris at his home Tuesday, Oct. 9, 2018, in Keaton Beach, Fla. Sandousky has ridden out several storms since he moved to the area some 40 years ago. Hurricane Michael continues to churn in the Gulf of Mexico heading for the Florida panhandle. (AP Photo/Chris O'Meara)

Krystal Day, of Homosassa, Fla., leads a sandbag assembly line at the Old Port Cove restaurant Tuesday, Oct. 9, 2018, in Ozello, Fla. Employees were hoping to protect the restaurant as Hurricane Michael continues to churn in the Gulf of Mexico heading for the Florida panhandle. (AP Photo/Chris O'Meara)

Krystal Day, of Homosassa, Fla., left, leads a sandbag assembly line at the Old Port Cove restaurant Tuesday, Oct. 9, 2018, in Ozello, Fla. Employees were hoping to protect the restaurant from floodwaters as Hurricane Michael continues to churn in the Gulf of Mexico heading for the Florida panhandle. (AP Photo/Chris O'Meara)

This satellite image made available by NOAA shows Hurricane Michael, center, in the Gulf of Mexico on Tuesday, Oct. 9, 2018 at 3:17 p.m. EDT. (NOAA via AP)

An employee of Southern Electric Corporation from Flowood, Miss., climbs out of the cab of his truck after arriving at the Sarasota Fairgrounds Tuesday, Oct. 9, 2018. Florida Power & Light is staging their power restoration contractors in Sarasota, Fla., in advance of Hurricane Michael's expected landfall in the Florida panhandle later this week. (Mike Lang/Sarasota Herald-Tribune via AP)

Pike Electric power restoration workers wait instructions after arriving at the Saraosta Fairgrounds on Tuesday, Oct. 9, 2018. Florida Power & Light is staging contractors in Sarasota, Fla, in advance of Hurricane Michael's expected landfall in the Florida panhandle later this week. (Mike Lang/Sarasota Herald-Tribune via AP)

Surfers paddle past the St.Andrews State Park Pier Tuesday, Oct.9, 2018, at Panama City Beach, Fla. (Patti Blake/News Herald via AP)

Xavier McKenzie puts a twenty pound bag of ice into his family's car in Panama City, Fla., as Hurricane Michael approaches on Tuesday, Oct.9, 2018. He and his family do not live in a storm surge area, and instead prepared for losing power for days. (Joshua Boucher/News Herald via AP)

David Hayes boards up a window at this home in Panama City, Fla., as Hurricane Michael approaches on Tuesday, Oct. 9, 2018. (Joshua Boucher/News Herald via AP)

Julie Logsdon loads her dogs Tobias and Luna into her car in Panama City, Fla., as Hurricane Michael approaches on Tuesday, Oct. 9, 2018. She is evacuating with her husband, four pets and belongings that could get damaged if the house leaks. (Joshua Boucher/News Herald via AP)

National Oceanic and Atmospheric Administration public affairs officer Dennis Feltgen updates the progress of Hurricane Michael on a large map, Tuesday, Oct. 9, 2018, at the Hurricane Center in Miami. At least 120,000 people along the Florida Panhandle were ordered to clear out Tuesday as Hurricane Michael rapidly picked up steam in the Gulf of Mexico and closed in with winds of 110 mph (175 kph) and a potential storm surge of 12 feet (3.7 meters). (AP Photo/Wilfredo Lee)

Photo: Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Support real journalism. Support local journalism. Subscribe to The Atlanta Journal-Constitution today. See offers.

Your subscription to the Atlanta Journal-Constitution funds in-depth reporting and investigations that keep you informed. Thank you for supporting real journalism.

X