Viewers should receive whisper and or other alerts when weather such as tornadoes and flash floods are imminent in their area or other emergency situations that should be the priority of certain viewers.

There is too much world and too much weather to alert people in chat but it wouldn't be out of bounds to have these alerts appear as a window the viewer has to acknowledge before continuing to participate. After all these are viewers are no good to you dead.

As I write this there may be dozens of tornadoes all over Oklahoma. You can only alert those who have made their location available to you but it's important for you to take the steps needed to protect the viewers who could be sucked up into the atmosphere or flooded down a hillside at any moment.

Lot's of people in these areas are vigilant but plenty become desensitized to these relatively common events.

This is definitely something that you can do in several ways but I think it's important that you require the viewer to acknowledge that an emergency situations has been declared in their area.