Could a Category 6 be added to the hurricane scale?
Every week WAVE 3 meteorologist Tawana Andrew breaks down what we know and what we don't about the climate and weather here in Louisville.
Bill Burton: It's time for us to take a look at the Science Behind the Forecast as I am joined by WAVE 3 meteorologist Tawana Andrew. Good morning, Tawana.
Tawana Andrew: Good morning. Today we're talking about something that has really taken the weather and news world by storm, a different category of hurricanes.
BB: Taking it by storm, I see what you did there. We all know there's no such thing as a good hurricane. Category 1 is bad. Category 5 is horrible. But there's been talk of potentially adding in a Category 6 so what do we need to know about a potential Category 6, the pluses and the minuses of creating another category?
TA: Yeah, so hurricanes are ranked from 1 to 5 on the Saffir-Simpson scale. But the Category 5 storm you get sustained winds in excess of 157 miles per hour. Now, the recent study that everybody's been talking about proposes the need for a Category 6 storm as we are starting to see some stronger hurricanes across the globe. Just to break it down. A hurricane needs a couple of things to form. You'd need a tropical wave, which is basically an area of low pressure that travels across the ocean, warm water, so 80 degrees to a depth of at least 164 feet. You need thunderstorms, and you need low wind shear to help keep that storm from being ripped apart. So you have Category 5 with winds of excess of 157. But this study suggests that we have Category 6 with winds of over 192 miles per hour. So we've had storms that strong, yes. And we are seeing storms getting stronger because the warm ocean is getting even warmer. Over the last century global sea average temperatures have risen just shy of two degrees Fahrenheit. And according to some research a one degree Fahrenheit jump in ocean temperatures can increase a hurricanes wind speed by 15 to 20 miles per hour. So average sea temperatures have risen just shy of two degrees Fahrenheit, that's 40 miles per hour. That is a significant jump. So that really just puts it into perspective how warm the ocean has been getting, and the impact that can have on the wind speeds. ... So we are getting closer to that point where we could see more of the stronger storms with let's say 192 miles per hour. Now that I've said that I think I might have like freaked out a couple of people. But it's important to put this all into perspective, especially from a meteorological side of things, because yes, it could cover the increasing wind. But there is concern that it would diminish the current messaging that we have as meteorologists. So the National Hurricane Center classifies a Category 5 storm with catastrophic, that's the word they use, catastrophic damage that could leave an area "uninhabitable for weeks or months." So that kind of covers everything pretty well on its own. But there's concern that with Category 5, no longer the top category, that people would not take any risk as seriously as they should. Because remember, Category 5 is still winds of 157 miles per hour. So you still got to be paying attention to that and not just looking for you know, the top category of potentially Category 6.
BB: Now we have a much better understanding of the potential benefits and problems with a Category 6 hurricane. And we know this now because of the latest edition of Science Behind the Forecast with WAVE 3 meteorologist Tawana Andrew. Thanks for the knowledge, Tawana.
TA: Of course.
This transcript was lightly edited for clarity.