Calamity howler is a phrase used to describe someone who predicts or warns of impending disaster or catastrophe. There are several synonyms for this term, including doomsayer, alarmist, prophet of doom, and haruspex. A doomsayer is one who constantly predicts the end of the world, often using religious or mythical references. An alarmist is someone who exaggerates the severity of a situation, causing unnecessary panic. A prophet of doom predicts misfortune or disaster with a great deal of certainty. Finally, a haruspex is an ancient Roman diviner who predicted the future by examining the entrails of animals. All of these terms describe those who predict calamity, often with little evidence to support their claims.