Around 4:00 p.m. on Thursday many people in the path of the East Coast storm were startled. Not because of the storm, but because their smartphones buzzed, beeped, or started talking to tell them about it.
Some got a loud buzzing with an emergency alert image, explaining the meteorological warning. Others got a female robotic voice. Text popped up from the National Weather Service with a blizzard warning. In New York City, it read, "Take action within next hour" and "Blizzard Warning this area til 1:00 PM EST Sat. Perpare. Avoid Travel. Check media."
The messages were supposed to go to everyone in the area with properly equipped phones. Not everyone got them.
Those notifications, similar to ones issued during Hurricane Sandy, were what FEMA and the FCC call Wireless Emergency Alerts, or WEAs. They were designed to alert people via their phones about three types of emergencies -- imminent threats (including extreme or severe weather), AMBER alerts, and presidential alerts issued by the White House. The alerts, which are not done via text message, were launched last year in many parts of the country and in May 2012 came to AT&T, Verizon, Sprint and other carriers.
"We have close to 100 carriers that are providing the service," Chris Guttman-McCabe, a vice president at the CTIA, the wireless industry trade group, told ABC News back in November after Hurricane Sandy hit. "We purposely made it so people didn't have to sign up for the service. We worked with FEMA and others to make sure it doesn't get abused. That's when people will only really pay attention to it."
Guttman-McCabe said users can disable the imminent and AMBER alerts, but not the presidential ones.
"WEA messages ensure that emergency alerts will not be delayed by network congestion, which can happen with standard mobile voice and texting services," a FEMA spokesperson told ABC News in November.
But that means that they are also dependent on the carriers and the phones, which is why not everyone in the area got the blizzard warning.
"It's a technology upgrade," Guttman-McCabe said. "As new phones come out, there is extreme likelihood that they can receive these."
Most of the phones that are supported are smartphones; not older-style flip phones or clamshell phones.
Currently, Verizon offers at least 35 phones, including the iPhone and some of the recent Android phones, like the Galaxy Nexus and Galaxy S III. Verizon lists the phones on its website, though it does not include some of the newest phones that support the service.
The iPhone is missing from the list, but ABC News confirmed that the iPhone 4S and 5 on Verizon's network got alerts for the coming blizzard. The iPhone 4 did not recieve the notice.
AT&T, by comparison, only supports 11 phones. AT&T's iPhone 4S and iPhone 5 do not have the alert service. In November an AT&T spokesperson confirmed to ABC News that AT&T's LTE network does not currently support WEAs.
Sprint, like Verizon, also has a wide selection of phones. In fact, all the smartphones on the network released since 2011 support WEAs.
T-Mobile also supports over 10 devices, including the Nexus 4, the Galaxy Note II and the Nokia Lumia 810.
Apple also confirmed to ABC News in November that only Verizon and Sprint currently have the alert function. Apple added the WEA alert option in iOS 6. You can turn on the feature under the settings and notifications menus on the phone.
The feature is also supported on Android smartphones and is enabled automatically on many of them. Google said it has added alert cards to its Google Now service.
But Guttman-McCabe made it very clear back in November: The goal is to have this service on all phones.
"The goal is to get it out to as many people as we can," he said. "The percentage of people with access to the alerts will climb dramatically."