Tropical storm, heat dome, toxic air. Much of US faces extreme weather

Key Points:

• Potent thunderstorms are forecasted to bring flash flooding to the Midwest, Northeast, and Mid-Atlantic regions on July 20-21, following deadly flash floods in Texas, Arizona, and Utah that claimed at least eight lives.
• A tropical depression in the Gulf of Mexico is expected to intensify into Tropical Storm Bertha, potentially causing heavy rain and flash flooding along the Gulf Coast from Texas to the Florida Panhandle.
• A severe heat wave is impacting the central U.S., with heat indices reaching up to 116 degrees in parts of southern Illinois, western Kentucky, and southeast Missouri, prompting extreme heat warnings and advisories.
• Air quality alerts remain in effect across the Great Lakes and Midwest due to lingering smoke from Canadian wildfires, which has also caused poor air quality in Oregon and Idaho, posing health risks especially to vulnerable populations.
• The severe weather and heat wave are occurring simultaneously with toxic wildfire smoke, creating hazardous conditions across large parts of the country and prompting public health and safety warnings.