For example, if a storm is about to cross an interstate highway, CTA's might focus on quick actions to be taken by motorists in the path. If a tornado is developing over hilly or mountainous terrain, the CTA could be used to remind people that they will not see the tornado coming. The same concept applies when highlighting the storm's main hazards. If you're dealing with a bow echo, you would want to focus on the damaging wind potential. A potential tornadic supercell might warrant a CTA that highlights not only the tornado threat, but also the attendant hail and wind hazards.
Thunderstorms cover a wide spectrum and present a wide variety of hazards.
The same severe thunderstorm warning used to inform about a marginal storm producing dime size hail and 50 mph winds must also make people respond when a violent storm with baseball hail and 80 mph winds is bearing down on them. One of the ways to differentiate between the different levels of severe storms is by using the call to action portion of the warning. Including specific information about what is anticipated with the storm can be extremely effective. Some call to action statements should be reserved for those situations when storms present a genuine threat to the lives and property of those in the storm's path. Setting up CTA's in WarnGen One of the nice things about call to action statements is that they, in most cases, can be set up well in advance and are available with one mouse click when composing a warning or statement.