The US National Weather Service said it expects Tropical Depression Two to slowly gain strength, potentially resulting in tropical storm conditions in the Florida Panhandle starting late Monday.
The eastern and central Gulf Coast is likely to face areas of flash flooding through Thursday.
Meanwhile, severe thunderstorms are expected to form and move along a cold front and pass through the Upper Midwest on Monday and the Ohio Valley and Mid-Atlantic on Tuesday, the agency said.
The NWS issued a flash flood warning early Monday for Utah's Bryce Canyon National Park and Zion National Park, while a flood warning was raised for Milford. The state primarily falls under the service area of PacifiCorp's Rocky Mountain Power.
A flash flood warning was also issued for North California's Wadesboro, primarily served by Duke Energy (DUK).
In Texas, a flood warning was raised for Laredo, Cotulla, George West, Refugio, and Victoria. American Electric Power's Texas unit is the major power provider in these places.
The NWS issued an extreme heat warning early Monday for Arizona's Batesville, Jonesboro, Searcy, Russellville, Conway, Brinkley, Little Rock, Pine Bluff, and Monticello, primarily served by Entergy's (ETR) Arkansas unit.
A similar warning was issued for Mississippi's Cleveland, Clarksdale, and Greenville, where Entergy is the major power provider through its Mississippi unit.
Affected areas also included Storm Lake and Sioux City in Iowa, which primarily falls under the service area of Berkshire Hathaway Energy unit MidAmerican Energy and Alliant Energy (LNT).
The NWS also issued an extreme heat warning for small pockets of Nebraska, Missouri, and South Dakota.
South Dakota's Mobridge, primarily served by MDU Resources (MDU) unit Montana-Dakota Utilities, was placed under a red flag warning watch.
In California, a red flag warning was raised for Willow Creek, Weaverville, and areas near Crescent City and Garberville. These places are majorly served by PacifiCorp's Pacific Power, and PG&E (PCG) subsidiary Pacific Gas and Electric.
A fire warning was raised for Colorado's Granby.