The test will be happening city-wide, but officials especially want to know how the system works in places like Lower Manhattan.
Cell phones, officials say, are a vital link to notify residents if and when there's an emergency.
Between 10 a.m. and 3 p.m., certain cell phones will get text message alerts from the Office of Emergency Management. OEM will be testing six messages in all.
In New Jersey earlier this week, a similar test caught people off guard. Some Verizon customers were warned of a "civil emergency," but were not informed it was only a test.
Remember, what's happening in New York City is only a test, of a system that could keep people safe in the future.
New York and Washington, D.C., are the pilot cities for the program.
The notification service that will allow authorized government officials to send geographically targeted emergency alerts to enabled mobile devices on the AT&T, Sprint, T-Mobile and Verizon Wireless networks.
Those wireless devices that receive the test message(s) will emit an audible notification, regardless of the user's ring tone or volume settings. A notification will be displayed on the screen of the device with text that reads: "Severe Alert" or "Extreme Alert."
Users will see the following test alert when they open the WEA message: "This is a test from NYC Office of Emergency Mgmt. Test Message 1. This is only a test." Some WEA capable mobile devices may receive more than one message.
In addition to the OEM and FEMA test phones, a number of newer mobile devices sold to the public by participating carriers may be WEA-capable and may receive one or more of the test messages.
People who do not have WEA-capable mobile devices will not receive the test message(s). Due to the limited nature of this test, it is likely that most members of the public will not see the test message(s).
Get Eyewitness News Delivered