Extreme heat is the deadliest weather-related threat in the U.S. In Phoenix, heat kills more people than homicides each year. So the city is turning to an unlikely lifesaver: bags of ice. And the fire department is creating a new model in the battle against heatstroke. For our series, Tipping Point, Ben Tracy of Climate Central shows how this low-tech approach is saving lives.

The U.S. Department of Agriculture has said concerns about the New World screwworm's spread lessened enough to allow the movement of cattle from Mexico at a crossing in Douglas, Arizona.