How does WEA work?
national, state or local government authorities may send alerts regarding
public safety emergencies – such as evacuation orders or shelter-in-place
orders due to severe weather, a terrorist threat or chemical spill – using WEA.
The alerts from authenticated public safety officials are sent through FEMA's
Integrated Public Alert and Warning System (IPAWS) to participating wireless
carriers, which then push the alerts to cell phones and enabled mobile devices
in the affected area.