New ‘destructive’ level of extreme weather alert to be texted to phones from next month

When dark clouds are gathering on the horizon, Americans may receive a new, alarming text from the National Weather Service.

Beginning on 2 August, the National Weather Service will start issuing “Destructive” severe thunderstorm warnings via the Emergency Alert system to people's mobile phones, according to NBC 6.

Any severe weather can cause damage; hail can break windows and dent cars, lightning can destroy trees and kill people, and tornadoes can level entire towns. But not all storms are the same, so the National Weather Services has decided to include a “destructive” tag to its existing severe thunderstorm warnings when applicable.

According to the NWS, the new alert is meant to better convey the potential danger of thunderstorms when they roll in. This will bring the number of threat levels associated with thunderstorms to three; destructive, considerable, and base.

The NWS hopes the new system will prompt people to act accordingly when they receive warnings that a thunderstorm is expected to be destructive.

In order to be considered “destructive”, a thunderstorm will have to have at least 80mph (129kph) winds, or baseball-sized hail. Thunderstorms labelled “considerable” will have to have at least 70mph (113kph) winds or golf ball-sized hail.

“Considerable” storms will not activate an emergency alert text.

According to the NWS, only 10 per cent of severe thunderstorms will reach the “destructive” status, though that could grow as climate change continues to create the conditions for more powerful storms.

The majority of storms that reach that level of destruction are considered “supercell” storms, which often produce large hail, or the powerful derecho wind storms.

In addition to the Emergency Alert System, NWS warnings will also appear on weather.gov and NOAA Weather Radio.

While hurricanes, tornadoes and floods typically are the most feared weather events in the US for their sheer destructive potential, thunderstorms can cause substantial damage. Of the most damaging weather events in 2020, 22 were thunderstorms.

The most destructive thunderstorm in US history, a derecho in Iowa that nearly destroyed a town and cost $11bn in damages, occurred in 2020.

Climate change tends to exacerbate existing severe conditions; droughts are more extreme, hurricanes are more powerful, wildfires burn with more intensity. Thunderstorms and rainfall are no different. As the climate crisis worsens and average temperatures continue to climb, experts expect that average rainfall will also increase.

Warmer air holds more moisture, which will result in more rainfall. That will increase the intensity of short, severe weather events, like flash floods and thunderstorms.