The storm triggered destructive tornadoes and flooding and is linked to a car crash that left 10 people dead.
Meteorologists are worried another heat wave could be coming next week for the West, leading to an even higher wildfire risk on the horizon.
Flooding had already begun in the area overnight Friday into Saturday, with local reports of high water over roads and stranded vehicles.
As cash-strapped cities welcome Big Tech to build hundreds of million-dollar data centers in their backyards, critics question the environmental cost.
Highs above 100 degrees are forecast to last through the weekend, but an end to the heat wave is in sight with cooler temperatures expected early next week.
Wildfire concerns are increasing as the combination of high heat and low humidity produces flammable conditions ripe for rapid fire ignition and spread.
Tropical storm warnings were issued from the central Louisiana coast to the Alabama-Florida border as Potential Tropical Cyclone Three approaches.
Dozens of daily heat records have been shattered, including several all-time records. Hundreds more could fall by the weekend.
About 200 million people are projected to experience temperatures over 90 degrees over the next seven days, and 40 million over 100 degrees.
The National Hurricane Center in Miami said the storm emerged from a tropical depression swirling about 335 miles off of Cape Hatteras, North Carolina.
About 43 million Americans are under heat advisories as extreme heat exacerbates drought and wildfire conditions.
Drought "is not a temporary condition we can expect to go away, but rather something we have to deal with," one expert said.
Twenty-one million people were under heat advisories again on Tuesday, with temperatures expected to soar into the 90s and feel close to 100 degrees.
Temperatures will stay hot through midweek before cooler temperatures arrive Thursday and Friday
The Mescal Fire and the Telegraph Fire erupted amid a worsening drought.