Heads-up: FEMA is testing emergency alerts on phones today

If you get an emergency alert on Wednesday, don’t panic.

It’s part of test of the nation’s public alert and warning systems.

The test will begin at 11:20 a.m. PT/ 2:20 pm ET on Aug. 11.

You’ll only get the message on your phone if you’ve opted in to receive test messages.

No action is needed."'

If you want to opt in or out of test messages,FEMA has instructions on its website.

The agencysent a tweet Wednesdayreminding people about the test.

FEMA said this will let it run nationwide tests “without disturbing the public.”