Just checked homeland security’s new system of notification and they don’t have any alerts on their page. Seems like a 2 type alert system, general and specific.
Was just implemented on April 20 and the link on NorthCom goes to the intro page. So maybe the alert was to inform of the new system?
http://www.dhs.gov/files/programs/Copy_of_press_release_0046.shtm
Maybe, but seems a bit belated for them to be sending it out on a Sunday morning 10 days later...
Colonel, USAFR