A brutal heat wave now stretches across most of the country. Thousands live under excessive heat warnings as thermometers spike past triple digits in many states. Washington, D.C. expects set daily benchmarks this week. New York City turned cooling centers like museums and train hubs into relief zones for Fourth of July visitors. The city now braces for dangerous highs too . Forecasters spread warnings from the Midwest straight through the East Coast.
Doctors caution heat exhaustion and dehydration might turn deadly within hours. Cities opened extra rec centers and malls for relief . Forecasters see little change through the coming days .