Meteorological Twitter has been pretty quiet of late. In fact, the only real “hot-topic” cooking up is about heat—no surprise in the summer months. This subject is revisited every summer and it often has to do with criteria. What constitutes a heat advisory? How about an excessive heat warning? As the weather wise know, answers to those questions vary based on location. But there are some broader points to the heat narrative that inspire further discussion. Scientists always seem to want hard and fast rules—or certain thresholds. Does a certain ambient temperature need to be reached? Should it simply focus on heat index? How does time factor into the equation?