Are there Category 6 hurricanes? What to know as Hurricane Milton gains strength.

Topline

Hurricane Milton – the Atlantic storm that is expected to be “one of the most destructive hurricanes ever for West Central Florida” – fluctuated between the two most violent hurricane classifications in the run-up to its expected landfall, sparking debate over whether to introduce a Category 6 distinction since Climate change is increasing extreme weather events.

An aerial view of damaged homes is seen after Hurricane Helene made landfall in Horseshoe Beach. … (+) Florida, September 28, 2024.

AFP via Getty Images

Important facts

Milton, which is expected to make landfall Wednesday evening, was downgraded to a Category 4 hurricane Tuesday morning.

The hurricane reached sustained winds of 180 miles per hour on Monday, at one point classifying it as a Category 5 storm – the highest possible designation.

Descriptions of the storm's rapid intensification and destructive potential have reignited debate on social media over whether to add a sixth category to the Saffir-Simpson hurricane wind scale used by the National Hurricane Center, which classifies storms based on their sustained winds Category 5 speed (Category 5 storms have wind speeds of at least 157 miles per hour).

Earlier this year, two researchers from Lawrence Berkeley National Laboratory and the Space Science and Engineering Center argued that the increasing impacts of climate change may soon force the addition of a sixth hurricane category to describe storms with winds over 192 miles per hour.

Scientists Michael Wehner and James Kossin argued that the openness of the current wind scale has become “increasingly problematic for representing wind risk in a warming world” and warned that severe storms are likely to become more common as climate change increases.

The National Hurricane Center said in February it had no plans to add a Category 6 to its hurricane scale, and AccuWeather chief meteorologist Jon Porter said there was no evidence that adding an additional category “would improve preparedness or decisions.” .

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Surprising fact

Even if there were Category 6 storms, Milton wouldn't have been one of them. The storm's highest maximum sustained wind speed was 180 degrees Monday evening, 12 miles per hour less than the 192 miles per hour needed to improve the storm under the researchers' proposal.

Big number

5. This is how many storms between 1980 and 2021 could have been classified as Category 6, meaning they exceeded a maximum sustained wind speed of 310 km/h. Of these, only one threatened North America. Hurricane Patricia made landfall in Mexico in 2015 as a Category 4 hurricane, becoming the strongest storm ever recorded in the Western Hemisphere with winds of 215 miles per hour. The other four storms all occurred in the Western Pacific.

Important background

Climate change has not caused a significant difference in the number of hurricanes that hit the United States each year, but it is blamed for making the hurricanes that do form intensify. Higher temperatures allow for more intense evaporation, causing storms moving over warm oceans to attract more water vapor and heat, leading to more precipitation and stronger winds. Additionally, sea level rise increases storm surges, which pushes more water further inland during hurricanes. However, Category 5 hurricanes are rare. According to CBS News, only 42 tropical cyclones have reached Category 5 status since 1924. Of these, 18 have formed since 2003.

tangent

Hurricane Milton will move across Mexico's Yucatan Peninsula on Tuesday before crossing the eastern Gulf of Mexico. It is expected to reach the west coast of Florida by Wednesday evening. Milton's strength is expected to continue to fluctuate over the next day or so as it moves over the Gulf of Mexico, and will likely weaken slightly before reaching Florida, but the National Hurricane Center warns: “There is high confidence.” that Milton will remain an extremely dangerous hurricane if it reaches the state. Milton is expected to hit Florida just two weeks after Hurricane Helene before causing catastrophic flooding in parts of the southeastern United States. Helene's impacts moved further inland than expected, devastating western North Carolina and parts of eastern Tennessee. More than 220 people died from Helene's impacts, and hundreds more are still missing.