earliest ever presidential debate. what we know about how the current president and the former president are preparing. first, to that severe weather threat in the northeast. powerful thunderstorms, damaging winds, even possible tornadoes as 100 million americans across 27 states remain under heat alerts. in the heartland, the national guard is assisting residents in flood-ravaged northwest iowa. rivers are expected to crest over record levels. ike ejiochi reports from washington, d.c. somara theodore has the forecast. as americans seek relief, beachgoers beware. officials warn of a high risk of rip currents along the eastern seaboard and gulf coast. several recent drownings reported from florida to new york. what experts say you should do if you re cut in a rip current. the death toll rises in the deadly mass shooting in arkansas as authorities share details of how the incident unfolded in the parking lot of that supermarket. and what we are learning about the victims,