KANSAS CITY, Mo. -- Many Joplin residents either ignored or were slow to react to the first warning sirens about a massive and deadly tornado this spring, partially because of years of false alarms, the government said Tuesday.
In assessing the communications and warning systems used before and during the storm that killed 162 people, the National Oceanic and Atmospheric Administration said many people waited for additional information like seeing the tornado or a television or radio report about the urgency of the threat.
"The majority of surveyed Joplin residents did not immediately go to shelter upon hearing the initial warning," the report said, adding that those people "did not take protective action until processing additional credible confirmation of the threat and its magnitude from a non-routine, extraordinary risk trigger."
A "vast majority" of Joplin residents didn't respond to the first siren because of an apparent widespread disregard for tornado sirens, according to the report.
Richard Wagenmaker, a National Weather Service meteorologist in Detroit and leader of the assessment team, said it was unclear if the slow public response cost lives.
"It's really hard to tell how many people that perished in the tornado did not take shelter," Wagenmaker said during a conference call. "It was a very large tornado, so there were certainly a number of people who did all the right things, took shelter in the best available place, but still found themselves in situations that weren't survivable. So it's really hard to make that assessment."
The report also said the National Weather Service was overall well-prepared and "performed in an exemplary manner" and that the combined efforts from the weather service, emergency management and the public "saved many lives."
But there were also lessons to be learned, including beefing up the wording in tornado warnings, the report said. After the intensity of the storm was clear, the resulting warnings weren't worded strongly enough "to accurately portray that immediate action was necessary to save lives."