Category 4 Hurricane: What Could It Bring

Category 4 hurricanes, like Hurricane Laura (pictured above), can produce unimaginable destruction. 

There are four damaging and possibly deadly things all land-falling hurricanes produce: storm surge, extreme battering waves, extreme winds and torrential downpours. 

One of the most deadly elements of hurricanes for the immediate coast is a storm surge. Acting like a plow, the hurricane`s intense winds create a wall of seawater that piles up and slams into the coast at the hurricane`s landfall. 

Category 4 hurricanes can produce a storm surge 10 to 15 feet high that can push far inland, often destroying everything along the coast and flooding low-lying areas well ashore. Remember, much of the damage Category 4 Hurricane Katrina produced along the Mississippi coast in 2005 was due to the extreme storm surge. 2019's Hurricane Michael, a category 5 storm, surge was 14 feet at Mexico Beach on Florida Panhandle.

Evacuations are always ordered along the coast to mitigate the potential loss of life. Most people who ignore evacuation orders and decide to ride out a Category 4 or 5 hurricanes along the immediate coast often die when the storm surge destroys the structure they are staying in.

The storm surge is topped by high waves driven by a hurricane`s wind. Reaching at least 10 feet high in a category 4 and 5 storm, these waves can slam into seawalls, piers, jetties, and coastal dunes, destroying everything in its way. The water often erodes beaches and protective dunes, making an area more susceptive to the sea.

If the wave and surge wasn`t enough, winds inside the eye wall of a Category 4 hurricane, the most intense part of the storm, can easily exceed 130 mph! 

This brute force will destroy practically everything that isn`t made of concrete and anchored deep in the ground. Luckily, a hurricane loses it most potent winds once it marches inland, lowering the risk of extreme wind damage as it pushes further inland. Even so, inland areas could still see widespread tree and roof damage and prolonged electric outages. Tornadoes spinning up in a hurricane's outer rain bands is another danger from all hurricanes.

The fourth and most widespread damage from hurricane often comes from its torrential downpours. Hurricanes are just giant rain machines sucking warm tropical water into the atmosphere and dumping it as it moves inland. 

Depending on how fast or slow a hurricane moves over land, a large and powerful hurricane can dump 1 to 2 feet of rain in a short amount of time. Even higher amounts are likely if the hurricane hits mountainous locations like those in Jamaica, eastern Cuba and central Haiti, where 4 feet of rain is not out of the question.

This rain can produce extreme flash flooding and in mountainous areas, deadly mudslides. In the U.S., most hurricane deaths are caused by inland flooding due to a hurricane`s prolonged rain. 

Image: Satellite image of Hurricane Laura from August 26, 2020. (NASA/NOAA GOES Project)