FlorencioGuetaVargas’wifemadesurehehadsnacksandplen-tyofwaterthatsummermorning.“Takecare,”shetoldhimashelefttoworkataWashingtonstatehopsfarm.Hourslater,afamilymemberfoundVargas’emptypickuptruck.About2,000milesawayinLouisiana,TinaPerrittsatonherporch,eatingaBLTandenjoyingacolddrink.Ithadbeenmorethanfourdayssinceatornadoknockedoutherpower,leavingherswel-tering.ButPerrittwasn’tleavinghome.InTexas,JaredFarleyclungagaintoacellphonetower300feetaboveground.ThatJunedaytheheatindexsoaredtoover100de-grees.Hedoesn’trememberpassingout.Acrossthecountry,oneformofweatherkillsmoreAmericans,onaverage,thananyotherevent−deadlierthanfloods,tornadoes,windstorms,orhurri...