Californians and others across the West Coast were rattled awake early Thursday morning when a planned test of the ShakeAlert earthquake warning system misfired seven hours ahead of time.
The messages — each reading “TEST of the earthquake warning system” — blared on phones at 3:19 a.m. Thursday, startling awake users of the MyShake app across California, Oregon and Washington, according to system administrators and numerous people who received the messages. The alert came ahead of the planned Great ShakeOut earthquake drill, which was scheduled to take place at 10:19 a.m. Thursday. as a means to prepare the California and other areas of the nation for a large-scale earthquake.
State officials say the goal of the Shake Out is to encourage people to practice earthquake safety, and remind residents to keep their emergency earthquake kits well-stocked. About 10 million people are expected to participate throughout the state, including school children and many office workers.
A simple time zone mix-up is to blame for the erroneous early-morning test alerts, said Robert de Groot, a member of the U.S. Geological Survey’s ShakeAlert operations team.
The messages were delivered at 10:19 Coordinated Universal Time, rather than Pacific Time. As a result, they were sent seven hours ahead of schedule.
“It was just a simple twist in the code,” said de Groot. He added that the problem has since been corrected,
The previously-scheduled alerts for the correct time of 10:19 a.m. PT were still expected to be sent as planned.
The errant messages were only sent to people who had downloaded the MyShake app, and who had successfully installed the program on their phones. More than 1 million people across the West Coast have installed the app, though it’s unclear how many people have completed the setup process, de Groot said.
Messages planned as a part of the Great ShakeOut on Thursday morning will still only be issued to people with the MyShake App. In the event of a real earthquake — such as the 4.1 temblor that struck near the Sacramento County town of Isleton on Wednesday — additional messages also would be sent via other means, including through Google and through cell towers, similar to how Amber Alerts are issued.
de Groot acknowledged the inconvenience of Thursday’s misfired early-morning message. Still, he implored Californians to download the MyShake app, given how it could keep them safe during an actual earthquake.
“We understand what happened, and it’s been addressed,” de Groot said. “The people behind this know what they’re doing and they’re making every effort to make sure this never happens again.”
“This alert system, first of all, is a new tool for everyone’s earthquake preparedness toolbox — it’s an enhancement to what people already have,” de Groot added. “And the idea behind this is: It may give those critical seconds for people to drop, cover and hold on before the heaviest shaking arrives.”
To download the app, go to myshake.berkeley.edu.