"I just ordered a storm shelter." The text popped up on my cell this morning from my father, who lives about 20 minutes' drive north of the Oklahoma neighborhoods flattened by Monday's tornadoes.

My immediate reply was banal—something like "Good!"—but afterward it hit me. Something about this particular storm had spooked him. And that spooked me because in our family's past encounters with tornadoes, none ever truly appeared to rattle him.

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