The only time I've been upset by those local channel severe weather warnings/interruptions is when I'm watching a show from the DVR and the storm happened 3 days ago when I wasn't even in town.
U-verse also has an insanely intrusive EAS system - for a single storm event (just a severe thunderstorm, not even a tornado or a real EAS event), you'll receive no fewer than 4 alerts over the span of an hour (no matter what channel or on demand you are watching) - each alert plays the 3 buzzers, the old EBS tone, the 3 buzzers, and another EBS tone. Pressing exit only dismisses the alert box, it doesn't end the aural onslaught, which is so loud I have to press mute immediately. The final slap in the face is when you turn on another TV, two hours later, and one of the alerts is still queued up on the box and decides to play.
Since I've been conditioned now to press exit and mute so quickly after seeing a U-verse EAS alert, when an actual emergency does occur I won't know about it, at least from them.