Cellphone alerts startled Southern Californians for the second time this month on Thursday.
This time, it came in the form of an "Emergency Alert" issued by the National Weather Service and was connected to a dust storm warning.
The warning lasted until 8 p.m. and included much of far southwest Arizona and southeast California, according to NWS. It applies to eastern Riverside County, but residents in the western portion of the county reported getting the warning, as well.
A spokesman said the National Weather Service said more residents than intended received the alerts. They were meant for residents in the Coachella Valley and Anza-Borrego Desert area, but the mobile warnings creeped into metro areas in the Inland Empire.
The first alert came about 5:39 p.m. telling recipients the warning will last until 7 p.m. An updated second alert came at 6:50 p.m. with the news that the warning had been extended an hour.
NBC4 was contacted by several viewers who were concerned or confused about the alerts.
NWS's Rob Balfour blamed the excess alerts on outdated systems, not yet updated to be more selective. He said if customers think they received the message in error, they should call their wireless provider.
On Aug. 5, phones across the Golden State buzzed, beeped and whirred as California sent its first statewide Amber Alert to mobile devices.
Those alerts -- dubbed Wireless Emergency Alerts -- were delivered with a special tone and vibration meant to help people with hearing or vision disabilities get the warning.
NBC4 viewers said Thursday evening's dust storm warning came with that same tone.
They're part of the Wireless Emergency Alert program, which was created by the Federal Communications Commission (FCC) and Federal Emergency Management Agency (FEMA), and executed by wireless carriers on a voluntary basis.
NBC4's Tony Shin contributed to this report.
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