Heat, floods, and smoky skies: US faces extreme weather as Bertha brews

Forecasters expect Tropical Storm Bertha to form from a Gulf Coast depression, while a central U.S. heat dome drives dangerous heat (indices up to about 116°F) and a cold front could trigger severe thunderstorms with flash floods from the Midwest to the Mid-Atlantic; wildfire smoke from Canadian fires blankets the Great Lakes region, worsening air quality, and eight flood-related deaths have been reported in Texas, Arizona, and Utah.