Heat dome expands across US

Temperatures hit sweltering highs across much of the central US Saturday as forecasters warned that dangerously hot weather from Dallas to North Dakota would push into next week, with roughly 80 million people facing heat advisories. A heat dome, where atmospheric conditions trap heat, was forecast to create sustained high temperatures and accumulating discomfort. Meanwhile overnight lows were not expected to come down enough for people to have much chance to recover, allowing heat stress to bui