Today, I was able to make it up to Fort Oglethorpe, Georgia and see their Model 3 in 6 cycles of attack. This siren is an older Federal Signal Model 3, which was originally used as a fire siren but now serves as a severe weather siren. The sirens are tested on the first Saturday of the month at noon by the EMA, however this siren is manually activated using a Federal Signal pull station, and requires all of the firefighters to be at the station. I have never encountered an activation setup like the one used here, the pull station has a pin that can be inserted into three different holes, each of which sounds the siren for a different amount of time, with the first one sounding three cycles of attack, the second six cycles, and the third nine cycles. This siren sounds quite healthy and has a wind down that lasts around three minutes. Here is the video:
https://www.youtube.com/watch?v=UgLBOICU2t8
EDIT: This is actually a Federal Model 3, I have re-edited the video and changed the post/description. Thank you all for pointing that out!