Life-threatening thunderstorms can come in many forms and levels of severity. That's why the National Weather Service is adding two new categories to its Severe Thunderstorm Warnings.
You'll see these new alerts on your smartphone beginning July 28.
The three categories of damage threat are:
Destructive: This means damage threat is at least 2.17 inch diameter (baseball-sized) hail and/or 80 mph winds. This category will automatically activate a Wireless Emergency Alert (WEA) on smartphones within the area affected. This is the most severe damage threat.
Considerable: This damage threat is at least 1.75 inch diameter (golf ball-sized) hail and/or 70 mph winds. This will not activate a WEA.
Base or baseline: This category does not change. Its threat is one-inch hail and/or 58 mph winds. This will not activate a WEA.
Here is an example of a destructive alert, tweeted by the National Weather Service.
The National Weather Service says that 13 of the 22 costliest weather disasters in 2020 were severe thunderstorms and would have triggered the new "destructive" WEA alert. That includes the costliest thunderstorm in U.S. history — the $11 billion derecho that hit Iowa in August 2020.
The addition of the damage threat tags is part of the weather service's Hazard Simplification Project, the goal of which is to improve communication with the public.
All NWS severe thunderstorm warnings will still be issued and distributed through weather.gov, NOAA Weather Radio, the Emergency Alert System and partners.
The National Weather Service website has several ways to learn when a storm is expected and tips on how to stay safe in a severe thunderstorm, including before, duringand after severe weather.