A tornado emergency was declared in Arkansas but no twister confirmed


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Scary moments ensued Friday night near Jonesboro, Ark., when residents sought shelter ahead of a “confirmed large and destructive tornado.” The National Weather Service described the situation as “catastrophic” and “deadly.” It opted to declare a tornado emergency, its most dire alert — more urgent than a standard tornado warning.

The only issue? The Weather Service was unable to confirm that a twister had touched down in a damage survey conducted the next day. Reports of tornadoes and tornado damage, submitted to the Weather Service by volunteer storm spotters, may have been mistaken. A gap in radar coverage over the affected area also proved a factor, as meteorologists had limited data to corroborate the spotter reports.

In the aftermath of this incident, some meteorologists say the bar needs to be raised for declaring tornado emergencies to guard against this kind of false alarm.

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What is a tornado emergency?

Tornado emergencies are intended for the most urgent threats.

The National Weather Service defines a tornado emergency as “an exceedingly rare tornado warning issued when there is a severe threat to human life and catastrophic damage from an imminent or ongoing tornado.”

The term was pioneered when an F5 tornado was bearing down on the southern suburbs of Oklahoma City on May 3, 1999. More than three dozen people died in the mile-wide tornado.

Such emergency declarations are rare, but they tend to be accurate. An analysis posted to Twitter by Kaylan Patel, a meteorology student at the University of Wisconsin, found of 195 tornado emergencies declared since 1999, 92 percent contained a tornado. Jacob Feuerstein, a meteorology student at Cornell, tweeted the last tornado emergency false alarm occurred in February 2016.

How the tornado emergency unfolded

A single, rotating thunderstorm or supercell formed over north-central Arkansas during the mid-evening hours Friday, lining up well with an area the Weather Service’s Storm Prediction Center had encapsulated in a Level 2 out of 5 risk for severe weather. Very large hail and damaging straight-line winds were the primary hazards of concern, but the Weather Service wrote that “a brief tornado cannot be ruled out.” The Weather Service issued a severe thunderstorm watch but not a tornado watch ahead of the storm.

The supercell began dropping hail to the size of softballs over Viola, about 80 miles northwest of Jonesboro, around 7 p.m. Central time, roughly the same time that the Weather Service in Little Rock issued a tornado warning. The warning first came out at 6:49 p.m. but at 7:18 p.m. was upgraded to a PDS, or Particularly Dangerous Situation, warning. A PDS warning is considered more urgent than a conventional tornado warning but not as dire as a tornado emergency. The text bulletin alerted of a “confirmed large and extremely dangerous tornado” near Cherokee Village. Emergency management had reportedly confirmed a tornado.

By 7:35 p.m., the Weather Service declared the situation a “tornado emergency,” signaling that a massive tornado was churning through the dusky landscape. Two minutes earlier, a storm spotter had reported a “wedge tornado on the ground” near Hardy. The Weather Service also received a report of a roof ripped off a home and tossed into a gas station, as well as tree damage.

“This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!,” the Weather Service wrote.

At 7:45 p.m., the emergency was extended downwind into Imboden, Black Rock and Walnut Ridge, about 20 to 35 miles northwest of Jonesboro, for a “deadly tornado” as the storm pushed southeast.

Between about 8 and 8:15 p.m., the emergency was extended to Sedgwick, Fontaine and Bono, communities 10 to 15 miles northwest of Jonesboro, and into Jonesboro itself. “Cars have been flipped over Highway 67 in Walnut Ridge,” the Weather Service wrote. “To repeat, a large, extremely dangerous, and potentially deadly tornado is on the ground.”

Not until just after 8:30 p.m. was the tornado emergency dropped.

The next day, the Weather Service in Little Rock issued a public information statement following storm surveys of sporadic damage left in the storm’s wake. Meteorologists attributed the instances of damage to that of straight-line winds and “large wind blown hail.”

Reports of tornadoes “could not be verified,” the statement said.

The report of vehicles flipped in Walnut Ridge in Lawrence County was found to be not the result of a tornado but rather a car crash stemming from slippery conditions left by the hail.

False alarms are inevitable with tornado warnings, but tornado emergencies are supposed to be different. “This tornado warning is reserved for situations when a reliable source confirms a tornado,” the Weather Service writes, “or there is clear radar evidence of the existence of a damaging tornado, such as the observation of debris.”

A contributing factor may have been erroneous storm spotter reports submitted through the “Spotter Network,” or an interface that allows trained and/or registered storm spotters to share what they’re seeing with the Weather Service.

According to John Wetter, president of the Spotter Network, the report of a wedge tornado northwest of Jonesboro was the result of misinterpretation.

“We have verified that this report was made from the location stated in the report,” he wrote in an email. “The spotter believed the situation they were in met our reporting criteria and submitted a report.”

In reality, it is likely the individual was looking at “scud,” a ragged cloud formation that lurks under severe thunderstorm updrafts, or a curtain of rain or hail illuminated by lightning flashes.

The confirmation of tornadoes by emergency management and law enforcement northwest of Jonesboro was probably also the result of misinterpretation.

“From the best we can tell … that might have had to do with the nature of the storm and the topography and trees,” Dennis Cavanaugh, warning coordination meteorologist at the National Weather Service in Little Rock, wrote in an email. He explained that the very humid environment made for a ground-scraping wall cloud that may have looked like it was on the ground as a tornado.

“We believe all … reports of a tornado that night were made in good faith, [but] you need to rely on the perfect lightning strike at the perfect location behind the wall cloud to see what was happening below that cloud.”

On social media, some people asserted certain erroneous reports from spotters were made intentionally as a user had falsely reported a tornado east of Fort Smith, Ark., four days earlier.

“On April 11th near Little Rock, there was a false report entered,” Wetter wrote. “That report has been investigated and found to be false and administrative action has been taken for the individual who submitted the reports as soon as we became aware of the issue. The individual that sent in the reports is claiming their account was ‘hacked’ though we can find no evidence to support this claim.”

Regarding Friday night’s storm reports, Wetter wrote on Twitter, “there does not appear to have been malicious intent and there were not ‘fake’ reports with this event.”

Challenges with radar interpretation

Compounding the issue of the difficulty in detecting tornadoes amid darkening skies, weather radar was unable to provide corroborating evidence.

In the area where the tornado emergency was prompted, the nearest National Weather Service Doppler radar dome was located some 80-plus miles away. That meant no coverage below about 7,000 feet above ground level. Meteorologists had little way of knowing what was going on close to the surface.

Subsequently, they couldn’t ascertain whether rotation observed at the mid-levels of the storm was present near the cloud base.

“It was a weird night because our initial situational awareness was that this was not a tornado setup,” wrote Ryan Vaughan, chief meteorologist at KAIT-TV in Jonesboro. “But we all know anything can happen. Admittedly, I missed the initial ‘tornado emergency’ wording. I’m glad I did, because by the time I noticed it, I was starting to have some serious doubts about the storm having a tornado.”

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Vaughan said that he struggled to sift through the messy radar signatures but that they didn’t appear commensurate with a strong tornado.

“Radar signatures were a mess,” he wrote. “While on air, it’s tough to look at reflectivity, velocity, and correlation coefficient side-by-side and do a good analysis. With that said, even on the fly … it looked odd.”

He said he constantly jumped between data from Little Rock and Memphis to search for evidence of tornado-lofted debris, but he could find none.

In the wake of Friday’s episode, the National Weather Service defended forecasters at the Little Rock office who issued the tornado emergencies.

“When issuing warnings, our forecasters consider all available data, including radar, satellites, reports from storm spotters and local public officials, and sometimes the general public through direct reports or social media,” wrote Susan Buchanan, director of public affairs at the Weather Service. “Forecasters usually have only seconds to assess a large volume of data and make decisions.”

She wrote that the warning was issued based on radar data and storm reports. That said, the National Weather Service’s Southern Region headquarters is probing the event as part of an after-action investigation to determine whether the appropriate decisions were made.

“The NWS Southern Region Headquarters is assessing how forecasters arrived at the decision to issue a tornado emergency and will determine whether operational modifications are necessary for future events,” Buchanan wrote. “Any recommendations to modify the protocols will be raised to the national severe weather program.”

The occurrence of a false-alarm tornado emergency — an alert that is generally supposed to be bulletproof and issued in high confidence — is of concern to some in the weather community.

“I can only hope this debacle sheds light on the increasing issue of the number of high false alarms, constant hyperbole, and fearmongering before and during severe weather events,” James Spann, chief meteorologist for ABC 33 in Birmingham, Ala., wrote in a post on Substack. “The public is being desensitized, and tornado warnings are losing their meaning.”

Jason Samenow contributed to this report.




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