Signals 

Signals have Different Meanings Depending on which Statal Region you Live in. They have different Signals for Different Things. For Example: Plenty of Places in Arkansas use Hi-Lo for Lightning Warnings, Alert for Tornado Warnings, and Alternate Wail for Firecalls. Plenty of Places in Florida use Attack for Hazmat Outbreak Warnings & Pulse Steady for Hurricane Warnings. Plenty of Places in Colorado use Pulsed Wail for Avalanche Warnings.   

EX SIREN: Federal Signal EOWS