Storm warning system updated

Alexis Barker
NLJ News Editor
 
To kick off August, the National Weather Service launched its new notification system for severe storms. The system now includes three different categories: base, considerable or destructive. The service hopes the new system will give people information about storm threats as quickly as possible. 
“The big change is we added the descriptions — base, considerable and destructive,” said Susan Sanders, warning coordination meteorologist for the National Weather Service in Rapid City. “Most people don’t see the entire warning when they get the alert on their phone. This is an easy way, especially for the media, emergency management and dispatchers, to know a serious storm is coming that may need extra notification.”
According to the NWS website, a storm will be listed as destructive if there is a threat of at least 2.75 inches, or baseball-sized hail, and/or 80 mph thunderstorm winds. These warnings will automatically activate a Wireless Emergency Alert on smart phones within the warned area. 
“The most important point of the new system is that people will receive an alert on their phone, with a different tone than an app notification, for destructive storms,” Sanders said. “They will have to be relatively close to the warning area. If there is a destructive storm in the southwest corner of Weston County, Newcastle won’t get the warning because those incidents are localized.” 
The criteria for a considerable storm are hail at least 1.75 inches in diameter (golf ball-sized) and/or 70 mph winds. A baseline severe thunderstorm has 1-inch hail and/or 58 mph winds.
Considerable and baseline severe thunderstorms will not activate a WEA. 
On average, only 10% of all severe thunderstorms reach the destructive category across the country each year, the website states. Last year, 13 of the 22 costliest weather disasters were severe thunderstorms. 
According to Sanders, the seriousness of storms varies greatly. 
“We saw an increase in severe thunderstorm warnings after the Doppler radar. Before 1996, Wyoming didn’t have Doppler coverage, so we didn’t see them or how strong they could be,” Sanders said. “Now we have a lot more data and can look at different features of the storm. We also have more weather stations to see how strong the winds are from the storms.” 
In northeast Wyoming, she said, the severity of the storms varies with the amount of moisture in the area. Dryer years, for example, bring gustier winds and smaller hail, while high-moisture years bring larger hail and heavy rain. 
“This year, we are way down on the number of severe storm warnings issued; there hasn’t been enough moisture,” Sanders said. “Two years ago, we had a lot of warnings.” 
As of Wednesday, Aug. 4, there hadn’t been a storm warning issued since July 26, which Sanders said is “quite a spell for this time of the year.”
“In a typical year, by the end of July, we (the National Weather Service in Rapid City) have issued almost 250 severe storm warnings alone. This year, we are under 150,” she said.