Severe Weather

What is the highest category for a hurricane? What to know as Milton takes aim

Milton has started weakening slightly, but remains a ferocious storm that could land a once-in-a-century direct hit on Tampa and St. Petersburg

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UPDATE: Hurricane Milton is again a Category 5 storm as it barrels toward the Florida coastline, the U.S. National Hurricane Center said Tuesday afternoon. Milton had previously weakened to a Category 4 storm, but its wind speeds have increased once again past the Category 5 threshold.

Our original story continues below.

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As Hurricane Milton continues to to churn towards Florida, remaining a ferocious storm that could have damaging and life-threatening impacts, many are wondering just how high hurricane categories go.

Milton has started weakening slightly, but remains a ferocious storm that could land a once-in-a-century direct hit on Tampa and St. Petersburg.

So what will that mean?

Here's a look at the hurricane categories and how they work:

How high do hurricane categories go?

Hurricane categories are based on what is known as the Saffir-Simpson Hurricane Wind Scale.

The rating categorizes hurricanes on a scale of 1 to 5 based on sustained wind speeds, according to the National Weather Service.

"This scale estimates potential property damage," the NWS reports. "Hurricanes reaching Category 3 and higher are considered major hurricanes because of their potential for significant loss of life and damage. Category 1 and 2 storms are still dangerous, however, and require preventative measures."

The wind speeds are calculated using a one-minute average.

Here's how they break down:

Category One Hurricane

     Winds 74-95 mph. Very dangerous winds will produce some damage
 Category Two Hurricane

     Winds 96-110 mph. Extremely dangerous winds will cause extensive damage
 Category Three Hurricane

    Winds 111-129 mph. Devastating damage will occur
 Category Four Hurricane

     Winds 130-156 mph. Catastrophic damage will occur
 Category Five Hurricane

     Winds 157 mph or higher. Catastrophic damage will occur

In a Category Five storm, "a high percentage of framed homes will be destroyed, with total roof failure and wall collapse," according to the scale.

"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," the description states.

Is there a Category 6?

Earlier this year, some experts proposed adding a Category 6 to the ranking for storms with winds that exceed 192 miles per hour, though no such category has been officially created so far.

Several experts told The Associated Press they don't think that category is necessary. They said it could even give the wrong signal to the public because it's based on wind speed, while water is by far the deadliest killer in hurricanes.

What causes a hurricane?

A hurricane is a tropical cyclone with maximum sustained winds of 74 mph or higher that typically registers as a Category 1 or 2 on the Saffir-Simpson Hurricane Wind Scale. 

"Hurricanes are powerhouse weather events that suck heat from tropical waters to fuel their fury. These violent storms form over the ocean, often beginning as a tropical wave—a low pressure area that moves through the moisture-rich tropics, possibly enhancing shower and thunderstorm activity," the National Weather Service reports. "As this weather system moves westward across the tropics, warm ocean air rises into the storm, forming an area of low pressure underneath. This causes more air to rush in. The air then rises and cools, forming clouds and thunderstorms. Up in the clouds, water condenses and forms droplets, releasing even more heat to power the storm."

A Category 1 storm has sustained wind speeds between 74 mph and 95 mph, and a Category 2 storm is between 96 mph and 110 mph.

A major hurricane is a tropical cyclone with maximum sustained winds of 111 mph or higher that is classified as Category 3, 4 or 5.

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