I've seen people talk about the siren systems in their communities, so I decide I'll do the same.
I live in Midland County, Michigan in the City of Midland. The county and city, from my knowledge has one of the largest American Signal Systems within the state, as Michigan tends to be a predominantly Federal Signal dominated region.
There are two siren-types in the system: ASC RM-130s, and T-128s. The RM–130s are the original sirens. T-128s are found located throughout the city and rural areas of the county.
Tornadoes don't tend to be a major hazard since the City of Midland is located within the river valley. The largest tornado was a EF2 back in 1999. Chemical emergencies are a very big risk as Midland is the international headquarters of Dow Chemical, and Dow maintains a nuclear reactor.