The tour-group had gone to the plains of the region known as the United States and was at a museum that told of such things as the Great Depression, and how humans had caused such damage to their lands that this region even suffered a catastrophe known as the Dust Bowl, when a loud warning blared out. A particularly large tornado was on its way.
Fortunately, the place had shelters to survive even an F5 so no one was hurt, or killed, but physical damage isn't the only thing that can occur before, during, and especially after, a major storm like that has passed through. -- Anon Guest
Bad news: Deathworlds were host to extreme weather. Good news: The Deathworlders are already prepared for this. The sirens were creepy and deliberately designed to be alarming in more ways than one.The natives knew what they meant and many of them could be relied upon to help get any Havenworlders to safety.
There's always a few who are blasé to all but the most extreme of dangers, and even then they're never truly panicked. This has caused some upset and confusion amongst visitors. There's only so much that visitor's guides can prepare people for. Especially when most visitors only glance at the most important bits to them and leave the rest unviewed.
Public Service Announcements have helped the locals to help the visitors immensely. In this case, the Havenworlder tourists were ushered to a shelter and distracted from the noise of the storm. At which point, the people who were used to the tornadoes left to survey the damage. They assumed that the big danger was over and all would be well. Public Service Announcements can only do so much, after all.