On April 22, an EF-4 tornado struck St. Louis, inflicting heavy damage on Lambert-St. Louis International Airport. Here at CWG, we’re running a two-part investigative series about the event

Here’s Part One, which explores the lack of warning given to people within the airport terminals. Part Two focuses on how pilots are notified of tornado warnings.

(Originally posted at 11:00 a.m. on 5/13, updated at 6 p.m. and 7 p.m. after the jump with new information; and at 12:55 p.m. on 5/16)

Chef Carla Hall (Matthew D. Lyons)

Unbeknownst to Hall, most others in the airport, and even airline pilots, a violent tornado was heading straight for the airport.

The tornado that struck Lambert Field has since been eclipsed by the devastating and historic outbreak that swept across the South about a week later, killing more than 300 people. However, the St. Louis tornado revealed important gaps about aviation safety, including how airport authorities, airline pilots, and passengers receive severe weather information.

With Hall awaiting her flight at Concourse A, Nora Losciale, 27, sat reading a book near the entrance to security at Concourse C. She was waiting for her fiancé, Derrick Wendling, to finally get off his flight from Reno, Nevada. Wendling’s flight had landed around 7:15 pm, but the plane had stopped just short of its gate. With lightning in the vicinity, ground personnel - including baggage handlers and fuel service workers - were not allowed onto the ramp area, and the plane could not proceed to the gate without their assistance.

On board the American Airlines MD-82 jet, Derrick, 30, sent Nora a text message, letting her know that it might be a while. For an hour he sat through a series of announcements from the flight deck, each time telling him that it would be “another 15 to 20 minutes” before the plane would be allowed to proceed to the gate.

As 8 pm approached, Nora could hear the slightly muffled sound of St. Louis County tornado sirens wailing in the distance. Because there were no announcements over the airport public address system, however, and business seemed to be going on as usual, she says she was not concerned about a tornado.

After all, St. Louis lies in the heart of tornado country, and natives such as Ms. Losciale are often accustomed to the sirens, which sound false alarms as well as the real deal.

Path of tornado that tracked through Lambert St. Louis international airport (approximate airport location superimposed) (National Weather Service/adapted by CWG)

This time, the tornado warning was on target, and the tornado that first touched down on the northern edge of Creve Coeur Lake at about 7:55 pm was proceeding swiftly towards the airport.

While Nora waited patiently for Derrick to get off his flight, the tornado was chewing up nearby residential neighborhoods, such as Bridgeton, which sustained the worst of the damage.

For Nora, the tornado hit suddenly and without warning. First, there was a gush of air from the sliding doors, then the lights shut off, emitting loud “popping” sounds. Glass began shattering and raining down within the concourse, and American flags fell from the ceiling. X-Ray bins were tossed into the air.

Raw footage from a security camera inside Lambert airport as the tornado strikes (the most intense action is between 30 and 50 seconds)

“It was kind of like literally a disaster movie, that’s what it felt like I was in,” Losciale says.

Losciale says she would have heard announcements from her seating area had there been any. There were “no announcements... not a word,” she said. Referring to airport authorities, she said sarcastically, “If they had said anything that would have been helpful.”

A woman seated nearby sprang to action and yelled for others to head for the bathrooms to find shelter. “She said to run and everybody did. There were TSA agents standing near me [in the bathroom],” Losciale says, noting that they too were unaware of the tornado until it actually took place.

“... it all happened literally within 15 to 20 seconds, by the time we got to the bathroom area it was all over.”

Losciale was not injured, although she saw people with cuts and bruises who were treated at the scene.

She says the last text she received from her fiancé before an anxious two more hours of waiting was to ask whether she had “ever felt turbulence on the ground in a plane” before.

Tornado, Meet Airplane

Trapped on the plane, parked about 20 feet short of the gate, Derrick and his fellow passengers didn’t know that a tornado warning was in effect. When the tornado hit, he too was shocked by its sudden ferocity, although he didn’t know for sure whether it was a tornado or just severe thunderstorm winds.

He says the captain had permitted passengers to move about the cabin during the delay, but when the plane began shaking violently back and forth due to the strong winds, he made an urgent announcement for everyone to be seated immediately. “It literally felt like turbulence on the runway,” Wendling said.

After the tornado passed close to the aircraft, Wendling had to wait for another two hours before airport authorities maneuvered a bus past debris - including overturned baggage carts, tree branches, and pieces of roofing material - to pick them up.

Like Losciale, Carla Hall also says there was no warning given to passengers waiting in the terminal area

She was sitting in a Delta Airlines gate area when the lights went out in the airport terminal. “At that point I heard a loud boom, and then the security guards were running through, and I heard the [tornado] sirens,” she said.

The guards, Hall says, “were running through and they were like, “this is not a drill, everybody in the bathroom.”

Hall says she remained relaxed throughout the experience. “I’m really calm. I don’t know if that’s from Top Chef or whatever, but if you’re ever in an emergency, you want me on your team,” she said.

Hall says it was clear from their cavalier attitude prior to the storm that the airline employees in the gate area did not know about the tornado warning. “I don’t think that the flight attendants knew,” she said. “They didn’t tell their people because there was no way we would have been sitting there. We were at the gate until the lights went out.”

Where was the warning?

The experience of Hall and Losciale raises the important question of where the breakdowns in communicating and taking action on the tornado warning occurred. Update Friday, 6 p.m.: The airport confirmed it received the tornado warning when it was issued 34 minutes prior to the storm’s hitting the airport, but did not take action until it received more specific information about the tornado’s track.

Jeff Lea, a spokesman for Lambert-St. Louis International Airport, says the private forecasting firm, a Shawnee, Kansas-based company called Weather or Not, - was in constant contact with the airport that evening. [paragraph updated at 6 p.m. on 5/13/11].

Sara Croke, President of Weather or Not, says the company spoke with the airport three times as the tornado approached.

“We were on the phone about the track of the storm at the time the warning was issued,” she said. [quote added at 7 p.m. on 5/13/11].

Lea noted that tornado warnings can be issued for large portions of a particular county, and if the airport were to shut down each time a warning was issued - for a tornado at the other end of the county or for a false alarm - it would cause unnecessary travel delays.

In this case, once it became aware of a confirmed tornado on the ground west of the airport, the airport authority notified its emergency operations personnel, but did not have a chance to use the public address system before the tornado hit. Making an announcement via the PA system is the lynchpin of the airport’s emergency plan. “We did not get that information in time to be able to put out that alert,” Lea said. [paragraph updated at 7 p.m. on 5/13/11].

Update, 6:00 p.m. ET (05/13/11): Today Lea clarified the airport’s knowledge of and response to the severe weather that night, based on an investigation that took place after the author’s interview with him. He stated the following:

The Airport wants to clarify that our contracted weather service was in communication with Lambert throughout the evening in regards to the National Weather Service tornado warning issued on April 22, 2011. According to our information, based on an internal review that has occurred since the Washington Post interview... we verified that around 8:04 p.m., the Airport’s weather service alerted the Airport’s operations tower that a tornado had touched down west of the Airport and the tornado was tracking in a path toward the Airport. Simultaneously, our operations staff got a visual of the tornado and evacuated the Airport’s operations tower. They did not activate a public address warning throughout the Airport.

Separately, the airport police got word of tornado damage just west of the airport and also obtained a visual of the tornado, and began herding people who were in the drop off/pick up zones to shelter. [paragraph updated at 6 p.m. on 5/13/11]

Lea said the police were moving people to shelter outside Terminal 1, and he is aware of some efforts in Terminal 2 to move people to shelter as well. “We had lots of people moved into the restrooms prior to the tornado,” he said.

Lea said that although the focus right now is on getting the airport fully up and running again, there is also an assessment process underway to see what procedures may need to be changed. “Certainly there are lessons learned in any type of event,” he said.

Part II of this story examines the aviation weather issues this tornado has raised, including the firsthand perspective of a veteran Delta Airlines pilot who was sitting in the cockpit awaiting pushback from the gate as the tornado passed through.

(Capital Weather Gang’s Jason Samenow contributed to this story.)