On Wednesday, October 4, the Federal Emergency Management Agency (FEMA) plans a nationwide mobile alert test that will send an emergency SMS to all cell phones in the United States.

In coordination with the Federal Communications Commission (FCC), the national test will be administered at approximately 2:20 pm ET on Wednesday. It will consist of two portions that will test Wireless Emergency Alerts (WEA) and Emergency Alert System (EAS) capabilities.

The WEA portion of the test will be directed to all consumer cell phones.

The messaging will be displayed in either English or Spanish, depending on the language settings of the phone. The EAS portion of the test will be sent to radios and televisions.

FEMA and the FCC are coordinating with EAS participants, wireless providers, emergency managers, and others to prepare for this national test to minimize confusion and to maximize the public safety value of the test.

“The purpose of the test is to ensure that the systems continue to be an effective means of warning the public about emergencies, particularly those on the national level,” the FEMA website reads. “In case the October 4 test is postponed due to widespread severe weather or other significant events, the backup testing date is October 11.”