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‘Destructive’ thunderstorm warnings will activate emergency alerts on your mobile phone

Starting next week, you might be hearing your cell phone blaring with a loud emergency alert a little more frequently than in the past.

That’s because a new type of warning is being added to the list of weather alerts that will automatically activate the familiar, high-pitched beeping sound on mobile phones. Severe thunderstorms that are deemed “destructive” because of extremely intense winds or excessively large hail will trigger a mobile alert, starting Aug. 2, the National Weather Service has announced.

“The criteria for a destructive damage threat is at least 2.75 inch-diameter (baseball-sized) hail and/or 80 mph thunderstorm winds,” the weather service’s national office said. “Warnings with this tag will automatically activate a Wireless Emergency Alert (WEA) on smartphones within the warned area.”

(If you’re not familiar with the sound of a wireless emergency alert, check this YouTube video.)

But don’t get bent out of shape thinking your phone is going to be waking you up in the middle of the night every time a thunderstorm rolls across your town.

The weather service says only about 10% of all severe thunderstorms across the nation rise to the level of destructive. The new emergency alerts won’t be activated during routine summer thunderstorms or even severe thunderstorms with considerable damage threats, such as storms packing 70 mph wind gusts or golf ball-sized hail, 2.75 inches in diameter.

“You don’t want every single thunderstorm warning to be cell alerted,” said Valerie Meola, a meteorologist at the National Weather Service’s New Jersey forecast office. She noted the new alert is aimed at warning homeowners, drivers and mariners about storms “with the highest hazards, the ones that affect people the most.”

Automated mobile alerts are currently activated for rapid life-threatening weather events like tornadoes, flash floods and snow squalls. Destructive thunderstorms will now be added to that list.

Thunderstorm warnings - new emergency mobile alerts

Severe thunderstorms that are deemed “destructive” because of extremely intense winds or excessively large hail will trigger an emergency mobile alert, starting Aug. 2, 2021.National Weather Service

Meola noted some thunderstorms can generate intense straight-line winds — those blowing in the same general direction — that can cause as much damage as the fierce rotating winds of a tornado. That’s why weather forecasters believe the new mobile alert is warranted.

“The new destructive thunderstorm category conveys to the public urgent action is needed, a life-threatening event is occurring and may cause substantial damage to property,” the weather service’s national office says.

Although the weather service is the agency that issues thunderstorm warnings, wireless emergency alerts are automated and set up by mobile phone carriers, with coordination from the weather service, FEMA and other emergency management agencies as part of the national Wireless Emergency Alerts system.

The alert system, known as WEA, was launched by the federal government in 2012 to inform the public about dangerous weather and other types of emergencies, including Amber Alerts for missing children. The alerts are transmitted to cell phones and other mobile devices in targeted geographic areas.

Tropical Storm Elsa triggers emergency alerts

In early July 2021, Tropical Storm Elsa triggered three tornado warnings along the Jersey Shore. One of the emergency mobile alerts looked like this.

“These warnings are not coming from your phone’s weather app,” says Fox 29 in Philadelphia. “Instead, they are based on the GPS location of your cell phone, and you can turn them on or off in your phone’s settings.”

However, not all wireless carriers allow consumers to turn off the emergency alerts, according to the Federal Communications Commission.

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Len Melisurgo may be reached at