MARISSA PARRA HAS MORE FROM A SWELTERING PHOENIX. >> Reporter: OVERNIGHT, FAST-MOVING WILDFIRES OUTSIDE OF L.A. LEAVING RESIDENTS FLEEING FOR THEIR LIVES. EVACUATIONS UNDER WAY IN RIVERSIDE COUNTY, AS THREE FIRES RAVAGE HOMES AND RIP THROUGH THOUSANDS OF ACRES. >> VERY SCARY, YEAH. >> Reporter: THE FLAMES FEASTING ON LAND BAKING IN THE SUN. >> WE ARE IN THE MIDST OF A HISTORIC HEAT WAVE. >> Reporter: THOSE HIT HARDEST ACROSS THE BOARD, PEOPLE WHO WORK OUTSIDE, AND THOSE WITHOUT HOMES. AS PEOPLE BREAK A SWEAT, THE HEAT COULD BREAK RECORDS IN 14 DIFFERENT STATES THIS WEEKEND. AND IT'S NOT JUST OUT WEST. IN MUGGY MIAMI, FLORIDA, IT FEELS LIKE 107. IN ARID, ARIZONA, PHOENIX FIREFIGHTERS ARE FEELING THE STRAIN. PHOENIX FIRE CHIEF SHOWS US HOW HIS TEAM GOES ON CALLS. >> BURIED UNDERNEATH ALL THIS ICE, THERE'S OUR IV FLUIDS THAT WE'RE GOING TO GIVE THEM. >> Reporter: THEIR TOP PRIORITY, KEEPING PEOPLE HYDRATED AND COOL. >> ICE PACKS. A LOT OF ICE PACKS. >> Reporter: STAYING COOL ISN'T EASY, BUT YOU THINK IT'S JUST HOT OUTSIDE, TRY GETTING INTO ONE OF THESE CARS. THIS DASHBOARD, ALMOST 165 DEGREES. AS PHOENIX SEES TEMPS OVER 110 DEGREES FOR THE 16th STRAIGHT DAY, HOSPITALS, TOO, ARE SEEING A SURGE IN HEAT-RELATED ILLNESS AND BURNS. THIS DOCTOR HAS BEEN WORKING AT THE E.R. AT VALLEYWISE HEALTH HOSPITAL FOR 30 YEARS. HOW DOES THIS COMPARE TO SUMMERS PAST? >> THIS HAS BEEN THE WORST. >> Reporter: AS THE SUN HEATS UP OUTSIDE, INSIDE, THEY PREPARE FOR MORE PEOPLE NEEDING A LIFE OR DEATH COOLDOWN. >> YOU WANT TO BURY THE PATIENT IN ICE. >> Reporter: THIS COULD SAVE THEIR LIFE. >> OH, ABSOLUTELY. QUICKER YOU CAN GET THEIR TEMPERATURE DOWN, THE BETTER. >> Reporter: THE PACE OF CALLS AND TEMPERATURES SHOW NO SIGNS OF COOLING YET. WHILE IN DEATH VALLEY, NATIONAL PARK RANGER MATTHEW LAMAR GETTING READY FOR WHAT COULD BE A WORLD HEAT WORD THIS WEEKEND. >> IT COULD BE THE THIRD TIME IF FOUR YEARS WE HIT 130. THIS HEAT CAN BE DEADLY, AND IT'S NOT SOMETHING TO TRIFLE WITH. >> Reporter: MARISSA PARRA IS IN PHOENIX. WHAT ELSE DID YOU LEARN AT THAT HOSPITAL TODAY? >> Reporter: JOSE, WE SAW PEOPLE LINED UP IN THE HALLWAYS ON STRETCHERS, HOOKED UP
