so I did some more digging and found a web site with more info. Here's a basic breakdown:
- Presidential Alerts – Alerts issued by the President or a designee;
- Imminent Threat Alerts – Alerts that include severe man-made or natural disasters, such as hurricanes, earthquakes, tornadoes, etc., where an imminent threat to life or property exists; and
- AMBER Alerts – Alerts that meet the U.S. Department of Justice’s criteria to help law enforcement search for and locate an abducted child.
I can't find anything saying the difference between "Extreme" and "Severe", but at least this give me a general idea. If anybody's interested in learning more info on it, here's where I found the snippet above:
Wireless Emergency Alerts on Your Mobile Device
Also here's Verizon's FAQ regarding these alerts:
Wireless Emergency Alerts FAQs | Verizon Wireless