The Federal Emergency Management Agency said it would conduct a national test of its Emergency Alert System and Wireless Emergency Alerts beginning at 2:20 p.m. ET on Aug. 11.
In partnership with the Federal Communications Commission, the agency said the test would be broadcast as a test message nationwide through radio and television EAS participants and WEA wireless provider participants.
FEMA added that people who have opted-in to receive messages on their phones would receive the WEA test messages.
The message will say, "Emergency Alert. This is a test of the National Wireless Emergency System. No action is needed," according to the agency's Facebook page.
FEMA said the message would the WEA test will appear in English or Spanish depending on the language set by default.
The system was launched to allow governing bodies to alert and warn the public of natural disasters, acts of terrorism, dangerous weather or missing children.
This marks the second time a nationwide WEA is being tested, the first happening in 2018. But the Aug. 11 test will be the first time users will be able to opt-in, FEMA said.
If the test cannot happen on Aug. 11 due to a "real-world event," the test will take place on Aug. 25.