A sprawling storm system is sweeping across the southeastern United States, bringing torrential rain, flooding, and severe weather threats to more than 36 million people from the Gulf Coast to Virginia. Forecasters warned Monday that parts of Florida, southern Georgia, and Alabama could receive as much as 10 inches of rain-equivalent to two months' worth-before the system moves north into the Mid-Atlantic.

Flood watches were issued for major urban centers across South Florida, including Miami, and extended through central Alabama and the Carolinas. The system marks the most significant rainfall event for the region since Hurricane Helene in 2018, according to AccuWeather meteorologists.

This is a system with embedded thunderstorms capable of producing "a tornado or two, localized damaging winds and hail," the Storm Prediction Center stated. Accumulations of at least 2 inches are expected across a dozen states.

The same system sparked weekend tornadoes in Florida, including in the cities of Destin and Esto. As the rain intensified Monday, flash flooding inundated roadways in Central Florida. Impacted areas include Pershing Avenue and South Goldenrod Road in Orange County, Eagle Circle near Red Bug Lake Road in Seminole County, and Crestwood Circle in Osceola County.

Meteorologist T.J. Springs of FOX 35 warned that "with increasing wind energy, the potential for all types of severe weather is on the rise," highlighting hail, damaging gusts, and the possibility of brief tornadoes.

Air travel faced widespread delays as storms disrupted operations at multiple hubs. More than 40 flights were canceled and 90 delayed at Miami International Airport, where departures were held up by an average of 90 minutes, according to FlightAware and the FAA. Ground stops were possible at Tampa, Miami, and Atlanta airports.

Power outages spiked Monday as strong winds and heavy rain swept through Florida, Georgia, and Alabama. PowerOutage.us reported more than 20,000 customers without electricity across the three states, including over 9,500 in Florida. Miami-Dade and Broward counties reported the highest outage concentrations.

Severe Weather Team 2 meteorologist Brian Monahan cautioned that Monday's system could deliver multiple bands of rain and thunderstorms, with a "low but non-zero" risk of a spin-up tornado.