Hurricane Isaias was the only hurricane to make landfall in Myrtle Beach last year, and it was only a Category 1 storm.
So, we didn’t see much damage during last year’s hurricane season, right?
In 2020, the National Weather Service reports that the northeast South Carolina and southeast North Carolina region had local impacts from 10 different tropical cyclones, including one direct hit (Isaias) and 15 tornadoes produced by those storms as remnants moved through the region.
Some areas also saw significant rainfall with the potential to produce flash flooding. Pawleys Island, for one, saw 6.8 inches of rain during Hurricane Isaias.
After last year’s historic hurricane season, which saw nearly 30 named storms (twice what the NWS expected), 12 of which made landfall. They brought devastation across much of the Gulf Coast, and the NWS says its more important than ever to think beyond a storm’s “category” or distance from affected areas.
“Don’t just focus on on the category because it has a significant amount of limitations that can be, unfortunately, very costly and deadly,” NWS meteorologist Mark Willis said.
Just a Category 1 hurricane?
Since 2010, Category 1 hurricanes — Superstorm Sandy and Hurricanes Florence and Dorian, among them — have caused 175 direct deaths and $105 billion in damage.
“The Saffir-Simpson scale (the system of hurricane categories) is just one part of the puzzle,” NWS meteorologist Steve Pfaff said. “We need to think holistically in terms of impacts that a hurricane can bring. That would be storm surge, tornadoes, the rainfall, the inland flooding, in addition to any wind related hazards and marine and surf related hazards to rip currents.”
“Remnants” of hurricanes can also wreak havoc, Willis said. Even if a hurricane or tropical storm has been “downgraded,” it can still be incredibly dangerous.
“Those remnant systems are a force to be reckoned with. We cannot let our guard down even after those things weaken and move inland,” said Willis, the meteorologist-in-charge at the Wilmington NWS station.
The NWS said it’s important for the Grand Strand to not let its guard down when it comes to hurricane preparation after having a relatively light season last year. It’s been awhile since we’ve seen a major direct hit, but that doesn’t mean one won’t happen this year.
Hurricane Florence made landfall in North Carolina as a Category 1 hurricane but was one of the most disastrous storms to reach the Carollinas because it moved slowly over the states and flooded many areas with heavy rainfall. The storm caused $24 billion in damage and resulted in 52 deaths, according to the NWS.
Florence also was a prime example of a “flood in disguise,” Pfaff said.
“(Hurricanes) Matthew, Florence produced a phenomenal amount of rainfall that caused a lot of life threatening flash flooding,” Pfaff said. “Most of the loss of life with those storms was attributed to flash flooding or people were swept away in vehicles. We need to be very careful when we’re out and about after a hurricane moves through.”
Outside of Hurricane Isaias last year, the Grand Strand saw a “litany” of other storms affect the region. Many of them were lower level storms.
“The impacts ranged from flash flooding to gusty winds and trees being knocked down,” Pfaff said. “We had 15 tornadoes from four of these, including Isaias, that caused some destruction in our communities, in the rural areas around them.”
What’s the current climate for hurricanes?
This year, the National Oceanic and Atmospheric Administration expects 13-20 named storms, 6-10 hurricanes and 3-5 major hurricanes (Category 3 or higher).
There are three main conditions to consider when analyzing what the hurricane season will look like: the Atlantic Multi-Decadal Oscillation, whether we are in El Niño or La Niña and wind coming off the Sahara Desert in Africa.
We have been in the “warm” phase of the Atlantic Multi-Decadal Oscillation since. That means we are facing a greater chance of tropical weather formation due to the higher temperatures, which provides “fuel” to hurricanes. The NWS said we could be stuck in this phase for another 5-10 years.
Last year, we experienced La Niña, which pushes the jet stream northward and reduces wind shear in Caribbean Sea and tropical Atlantic basin, prime hurricane forming regions. Without that wind shear, it’s easier for hurricanes to form, according to the NWS. This year, the NWS said that the Atlantic is in the “neutral” area between El Niño and La Niña, so there is still a greater chance of hurricane formation.
Finally, the African Easterly Winds can serve as a bolster against hurricane formation. When in action, they push dry air off of the Sahara Desert across the Atlantic, draining it of humidity, according to the National Oceanic and Atmospheric Administration. It’s a lot harder for hurricanes to form without moisture in the air.
We most often see the affects of the African Easterly Winds in the form of dust that makes the skies across parts of the southeastern U.S. look hazy during the summertime. While it might not be the most picturesque experience, that dust is a sign of limited protection from tropical weather.
These winds are very unstable, NOAA says, and will often only affect a few days or weeks or a hurricane season rather than staying in place.
“We had it for part of the year last year, but it went away, leaving a great environment with respect to moisture in the atmosphere for the peak” of hurricane season, Pfaff said.
Even in years of lighter hurricane activity, like 1992 when there were only 7 named storms, just one hurricane make the difference. Hurricane Andrew that year caused $26.5 billion in damage, the most expensive natural date up to that point, according to the NWS
“All it takes is one hurricane to define a season,” Pfaff said. “We need to prepare that this is the year we’re going to have another hurricane because of the climatology (of) where we live and our history.”
Even far off hurricanes can bring damage
Category 5 Hurricane Lorenzo in 2019 halfway through its trek to the East Coast turned tail and went back out to sea. It was a relief for communities that might have been directly hit.
The storm, hundreds of miles offshore, still killed eight people.
Lorenzo sent rip currents traveling through the ocean to the East Coast. They landed on U.S. beaches at the same time that the region saw some of the best summer weather, Willis said.
“When a storm that powerful is sitting in an ocean anywhere near us — in this case even twenty two hundred nautical miles away — it will produce ... a rip current event and dangerous surf,” Willis said.
The accidents are a common element of distant hurricanes. People think the danger has passed, Willis said, and head to the beach. As a result, the majority of rip current deaths are connected to these far-off storms, according to the NWS.
It’s a particularly challenging problem because most of the people affected aren’t locals. The hometowns people who drown in North and South Carolina rip currents are concentrated in more inland parts of the two states but also stretch as far north as Vermont and as far west as California, the NWS said.