New evidence indicates that criticism was largely unwarranted. On Thursday, the National Weather Service in Lake Charles announced it found evidence that waters had crested at 17.2 feet above dry ground, or more than 20 feet above sea level, in Rutherford Beach, La. That’s just a few miles east of the Calcasieu River, whose lakes and channels would have provided a direct route for water to inundate Lake Charles, home to about 80,000 people.
This observation places Hurricane Laura’s surge among the top 10 highest on record for all landfalling storms along the Gulf Coast, ranking in ninth place.
Surge may have even topped 17.2 feet
Laura’s surge ranks just behind the rise in water of 17.5 feet (estimates vary) in Hurricane Ike, which made landfall along the upper Texas coast as a Category 2 in 2008. Category 5 Hurricane Michael brought a 16-foot surge in 2018 along Florida’s Big Bend.
A few hurricanes, including Katrina and Camille, have produced storm surges of 25 feet or greater.
Odds are that Laura’s surge could end up being even higher than the 17.2 feet measured thus far. Jamie Rhome, a storm surge specialist at the National Hurricane Center, said that numerous heights over 15 feet were measured.
“There was an Army Corps gauge that only measured once per hour … [but] at its peak, the surge was actually rising eight feet per hour,” he explained. “They went in and found the actual water rise was 19 inches above what it measured at the peak … in the 15-to-16-foot range.”
The United States Geological Survey also dispatched a crew, which found a 17.1-foot high-water mark close to two miles inland, Rhome noted.
“We haven’t yet determined the true peak, but it was probably higher than the 17.2 feet,” he said.
The National Hurricane Center is now trying to feed its findings into a backward-running model to simulate storm surge heights it wasn’t able to observe or measure.
Lake Charles spared the worst
Lake Charles avoided the brunt of Laura’s surge only thanks to a slight eastward shift in track at the time of landfall, which altered the wind direction enough to sweep a deluge of seawater into less populous stretches of southwestern Louisiana.
“We dodged a bullet in Lake Charles big time,” said John Brazzell, a hydrologist at the National Weather Service in Lake Charles, whose office evacuated ahead of Laura’s vicious onslaught. The service’s Doppler radar dome was obliterated by winds gusting over 130 mph in the eyewall.
“Meteorologically speaking, it was very close” to disaster, he recalled.
When a hurricane makes landfall, the surge is greatest on the eastern side of the eye, where winds scream onshore. West of the eye, the winds are offshore, mitigating the surge threat. In between, surge is more chaotic.
Lake Charles averted a surge catastrophe by only a few miles because the eye passed over the city. If the eye had passed even 10 miles farther west, it would have been a different story.
“Initially, the reason we evacuated the office [was because] we thought there would be two to three feet of water in the building,” recalled Brazzell. “That seemed pretty plausible given what we saw with Rita and Ike. Ike had a surge in the field across from the office, so [the risk associated with Laura] was very concerning.”
Behind the dire warnings
The original sobering language used in weather bulletins and warnings came from both the local National Weather Service in Lake Charles and the National Hurricane Center in Miami. Their storm surge estimates are a “reasonable worst case scenario” for what actually may pan out, representing a 90th-percentile surge prediction.
“It will look worse than what the actual storm surge will be, and that’s intentional,” Brazzell said. “We don’t know what’s going to happen hours before landfall. [In this case], it shifted north into a different place than what we had forecasted, but it was still in the forecast error.”
In other words, the National Weather Service compensates for potential uncertainty in track by communicating worst-case-scenario surge hazards in a broader geographic area, since it’s impossible to pinpoint in advance which locale within that zone will end up being slammed by the greatest surge.
Rhome was responsible for first using the word “unsurvivable” leading up to Laura’s landfall, a decision he made bearing in mind the counsel of social scientists and in light of the severe threat brewing.
“The aircraft reconnaissance kept coming in stronger and stronger,” he recalled. “We were trying to keep up with the aircraft, and no storm surge model could keep up with that. I basically just said ’15 to 20 feet, if amounts like that materialize, it’s unsurvivable.' ”
Initially, forecasters faced largely baseless and presumptuous accusations that Laura’s destructive potential had been overly hyped and unrealistically portrayed. But in light of recent data, it’s clear that’s not the case.
“The peak, be it the wind or the water, is never measured [by direct] observation,” said Rhome. “Have you ever seen a tornado winds in a [weather station] observation? Doesn’t mean the tornado didn’t happen.”
Rhome noted that many of the national television networks and other media were parked in Lake Charles, which did not experience storm surge flooding.
“People gravitate towards whatever information they can find. But they made the same mistake they always make,” said Rhome. “It takes days for disaster to be fully understood.”
“What if [the National Hurricane Center] hadn’t used that harsh language, and [Laura] did make landfall west of Calcasieu Pass and drove that surge straight into Lake Charles?” Rhome asked.
Meanwhile, back in Lake Charles, forecasters are getting settled into their facilities after nearly a month working remotely or being supported by other National Weather Service offices in the wake of Laura. The naked, dilapidated radar antenna outside the office stands as an eerie reminder of what happened barely a month ago.
“As of 8:00 AM this morning, NWS Lake Charles has resumed full operational responsibility,” the office tweeted Friday.