Idalia’s moving west to east. Would SC be hit harder if it came straight from the Atlantic?
Idalia’s path has steadily spun and strengthened from the western tip of Cuba, up into the Gulf and continued a northeast trajectory where it’s predicted to make landfall in the Big Bend area of Florida as a major hurricane early Wednesday.
Forecasters predict the now-hurricane’s track will cross the Florida Panhandle and continue to surge northeast into southeast Georgia and along the South Carolina coast late Wednesday evening into Thursday morning.
But what if Idalia’s path wasn’t anticipated to make a north-northeast arc with effects that rippled through the South Carolina coast? What if Idalia came directly from the Atlantic, without traveling over any land? Would the state see higher storm surge values, stronger winds, choppier surf or greater flood inundation?
Are they cut-and-dry answers? “Not necessarily,” said Meteorologist Brian Adam.
The further inland a storm tracks, areas that are on the more eastern or northeastern side of the storm have enhanced risk for a tropical tornado threat, Adam said. A storm coming straight off the Atlantic or riding along coastal waters doesn’t carry the same threat level.
When a storm system is coming up from the Gulf and crosses land before heading up to southeast coast, Adam said the storm has “an opportunity to weaken.” However, that doesn’t mean Idalia won’t pack a punch when she is expected to devolve into a Tropical Storm by the time she reaches the Lowcountry on Wednesday.
Some may think storms coming off the Atlantic “tend to be stronger because there’s nothing really impeding the storms, but that’s not necessarily the case,” Adam said.
Beyond a storm moving west to east or coming directly from the Atlantic, Adam said it’s the center of the storm that’s the biggest determining factor when it comes to wind and water impacts.
If the eastern or northeastern flank of the storm tracks over an area, because of its counter-clockwise circulation, it tends to be the “worst side,” resulting in more water being pushed inland. And if an area ends up on the other side of the storm, winds kick-up offshore not on land.
Further inland, Richland County will be on the western side of Idalia, predominantly getting northerly or northeasterly winds. Adam said, as compared to the coast, the winds will be weaker.
“For them, I would say, that it would probably be a weaker system coming up out of the southwest flight path versus something coming straight in from the Atlantic,” Adam said of Richland County. “I’m thinking of Hugo ... (it) slammed right into the Charleston area and those strong winds pushed pretty far inland because it was just straight in.”
Beaufort County is predicted to be on Idalia’s south-southeast side as the storm approaches, and once the center passes by, the winds will flip more westerly.
This story was originally published August 29, 2023 at 12:40 PM.
