Why do they name hurricanes names like "Katrina", and "Edna"?

I mean they sound so mellow, if I was about to get hit by a hurricane and heard on the news that hurricane Carol is about to hit, I wouldn't be scared. What if they name them something like " Sephorah the storm monarch! ", or " Maximus the destroyer!", or " Cranium the mighty FCK!". Now that's some scary sh*t. Who names these things anyway?