SIOUX FALLS, S.D. (MITCHELLNOW) Outdoor sirens in Sioux Falls will now go off for more than Tornado warnings.  The over 80 sirens across the city will now also sound off for a destructive severe thunderstorm warning.  That category includes dangerously high wind speeds or baseball-sized hail. A destructive severe thunderstorm warning will also activate the wireless emergency alert to mobile devices.  For more of your weather outlook, click here.