A National Weather Service Tsunami Warning sent out this morning was a test. No warning is in effect, and there is no danger to the public.
Smartphone users may have received the alert as a notice on their phones. Once a user clicked in to the story, it became apparent this was only a test.
The alert was issued by NOAA, and was sent to users on the Gulf Coast and East Coast.
The National Weather Service issued the following statement: "Our investigation into this routine monthly tsunami test message confirmed that it was coded as a test message. We are working with private sector companies to determine why some systems did not recognize the coding. Private sector partners perform a valuable service in disseminating warnings to the public. We will continue to work with our partners to prevent this from occurring again."
AccuWeather claims the warning was miscoded, causing it to be sent out by multiple outlets as a real warning. They add that the erroneous warning appeared on The Weather Channel and on the National Weather Service's own website as a real warning.
NWS and AccuWeather sent messages out via social media to alert the public that the warning was only intended to be a test and there was no threat.
AccuWeather also says this isn't the first time such a glitch has happened, having occurred some time around October 2014.