Vox's science and recode fellow Neil D'Naysha explains why it's so hard to talk about heat with any sense of real immediacy. Heat is the deadliest weather phenomenon in the United States, surpassing things that you might think of as more deadly like tornadoes and hurricanes. We've seen pretty devastating impacts around the world this year alone. And when you put them all together, we're just seeing heat wave after heatwave after heat wave coming and hitting everyone.