NWS Adding New ‘Destructive’ Severe Thunderstorm Warning That Will Alert On Your Phone

July 27, 2021

The National Weather Service is adding two new thunderstorm warning categories, one of which will trigger an alert of your phone.

Severe thunderstorms can be life-threatening, but not all severe storms are the same. Hazardous conditions range from tornadoes, large hail storms, and widespread straight-line winds called derechos, to cloud-to-ground lightning and flash flooding. Starting August 2, the National Weather Service will work to better convey the severity and potential impacts from thunderstorm winds and hail by adding a “damage threat” tag to severe thunderstorm warnings, similar to tornado and flash flood warnings.

The NWS developed three categories of damage threat for severe thunderstorm warnings. The categories, in order of highest to lowest damage threat, are destructive, considerable, and base. These tags and additional messaging are designed to promote immediate action, based on the threats:

  • The criteria for a destructive damage threat is at least 2.75 inch diameter (baseball-sized) hail and/or 80 mph thunderstorm winds. Warnings with this tag will automatically activate a Wireless Emergency Alert (WEA) on smartphones within the warned area.
  • The criteria for a considerable damage threat is at least 1.75 inch diameter (golf ball-sized) hail and/or 70 mph thunderstorm winds. This will not activate a WEA.
  • The criteria for a baseline or “base” severe thunderstorm warning remains unchanged, 1.00 inch (quarter-sized) hail and/or 58 mph thunderstorm winds. This will not activate a WEA. When no damage threat tag is present, damage is expected to be at the base level.

On average, only 10 percent of all severe thunderstorms reach the destructive category each year, nationwide. Most of these storms are damaging wind events such as derechos and some of the larger, more intense thunderstorms, called “Supercell” storms that can typically produce very large hail in their path. 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. Storms categorized as destructive will trigger a WEA to your cell phone.

Comments

2 Responses to “NWS Adding New ‘Destructive’ Severe Thunderstorm Warning That Will Alert On Your Phone”

  1. Evelyn L Owen on July 27th, 2021 11:52 am

    As one who owns Goats, I appreciate the warning, so I can get them into the stall under shelter and bring in the cat and take pictures of my vehicle (before). Wonderful Service!

  2. JTV on July 27th, 2021 6:11 am

    I’ll have to figure out how to turn this service off.

Written by William Reynolds · Filed Under News