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Why Helene is of particular concern to meteorologists
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Why Helene is of particular concern to meteorologists

The pit in my stomach is there. As a meteorologist, certain events cause that feeling because I know the potential impact and also my concern about whether the public understands the consequences. I had the same feeling with Hurricane Sandy (2012), Hurricane Harvey (2017), Hurricane Michael (2018), Hurricane Ida (2021), and Hurricane Ian (2022). Those storms caused catastrophic damage and loss of life. This is why Hurricane Helene is so concerning.

As I write this, Tropical Storm Helene is on the verge of becoming a hurricane. Hurricane hunters flying into the storm continue to find signs of strengthening. In fact, it may be a hurricane by the time you read this. The storm is currently moving slowly along the Yucatan Peninsula and will soon be in the Gulf of Mexico, where explosive rapid intensification is likely. The National Hurricane Center wrote Wednesday morning: “Over the next few days, Helene will move through an environment of low vertical wind shear, ample ambient humidity, and over waters with high oceanic heat content.”

The storm is expected to make landfall Thursday south of Tallahassee, Florida. Florida’s capital is where I spent my college years, and it will likely take a direct hit from a major hurricane (Category 3 or higher). That’s something I never experienced during my time at Florida State University, where I earned three degrees. I told my wife, whom I met in college, that Tallahassee will likely look very different on Friday morning. The current thinking is that at least a Category 3 hurricane like Helene will hit the region, and that could be on the conservative side. A Category 4 or higher is certainly possible.

A major hurricane brings with it extreme winds, extreme rainfall, storm surge flooding, and the potential for tornadoes. The sheer physical size of this storm should also be a major news story. NOAA weather forecasters go on to say, “Helene’s wind field is expected to grow to a very large size in the NHC forecast. Therefore, storm surge, wind, and rainfall effects are likely to extend far from the center and outside the forecast cone, particularly on the eastern side.” As you can see from the map above, tropical storm or hurricane watches/warnings cover the entire Florida panhandle and peninsula due to the expected storm footprint. I have been in the meteorological field for thirty years and I cannot recall ever seeing such an expansiveness in the warning and alert distribution.

The full range of risks will be seen across much of Florida. Storm surges could reach 8 feet in Tampa Bay and over a foot just to the right of the expected landfall. The total rainfall, even for a relatively fast-moving storm, will cause extensive flooding. Along the storm track, 8 to 12 inches of rainfall is expected. Due to orographic effects, in other words the terrain, mountainous areas of Georgia, South Carolina, and North Carolina could experience over a foot of rainfall.

Here in Georgia, a frontal system and ample moisture will bring rainfall on Wednesday before Helene arrives. It’s a classic Predecessor Rainfall Event. As University of Georgia weather expert Pam Knox explains in her blog, “Over time, scientists have noticed that some hurricanes and tropical systems generate areas of heavy rainfall well ahead of the main storm system… The presence of a front in the area along with strong moisture flow from the storm can enhance rainfall over that region, potentially leading to heavy rainfall that could cause flooding or set the region up for flooding once the main storm system moves over the PRE region.”

Helene’s expected forward speed is a “blessing” and a “curse.” It will leave Florida fairly quickly; however, it will not have much time to weaken as it enters Georgia. This means that hurricane conditions will persist well inland, and the official forecast track has an “H” over southwest Georgia. This seems to happen more often, but that’s another story for another day. Several counties in southern and central Georgia are already under hurricane or tropical storm warnings. Frankly, I expect those warnings to be extended to northern Georgia. It is almost certain that places like Atlanta and Athens will experience tropical storm conditions. The region should be prepared for power outages, downed trees, and flooding on Thursday and Friday.

I urge everyone in potentially affected regions to resist the urge to ignore these warnings or see them as “hype.” There’s plenty of that kind of thing out there, and I certainly understand the cynicism at times. This is not the time. If you’re reading this on a Wednesday, the window to prepare is closing fast.