So as somebody who grew up in a place without tornados and now lives in a place with them, let me be the first to say that when the dispatcher says:
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"If you decided to come back, that choice is yours," replied the dispatcher. "But I can tell you it won't be viewed as for your own safety. The safest practice is to stay exactly where you are. If you decide to return with your packages, it will be viewed as you refusing your route, which will ultimately end with you not having a job come tomorrow morning. The sirens are just a warning."
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that's just plain not true. I mean, yes, the sirens are technically just a warning. But they don't go off until things get really serious. If you hear them, you need to get to actual shelter as quickly as possible. They're not just some vague suggestion. I have no idea how some supervisor who presumably lives in a tornado region could not realize that!