Tropical Storm Debby live updates: Historic 10-20 inches of rainfall expected

Debby is roaring across Florida and Georgia as a tropical storm after making landfall as a Category 1 hurricane Monday morning.

At least four people have been killed.

Latest Developments

_{Aug 5, 11:44 PM}

Debby to bring historic 10-20 inches of rainfall: Forecast

Despite weakening since moving over land, Debby is still maintaining its tropical storm status, producing maximum sustained wind speeds of 45 mph.

As of 11 p.m. ET, over 150,000 customers in Florida and Georgia are still without power, according to PowerOutage.us .

With Debby's center about 35 miles west of Brunswick, Georgia, much of the heavy rain and showers have since moved out of Florida (except for the extreme northeastern corner of the state closer to the Georgia border). However, with the storm slowing down even more, Debby will stay stuck over the Southeast for the better part of this week, meandering over Georgia and the Carolinas.

Even though the storm is expected to weaken a bit more overnight, Debby is still expected to bring historic rainfall and life-threatening flooding to portions of southeastern Georgia and the coastal areas of the Carolinas over the next few days. Rainfall totals from this event are expected to reach between 10 and 20 inches.

Already, portions of southeastern Georgia and South Carolina have seen between 3 to 6 inches of rainfall, but with rainfall rates of 1.5 to 3 inches per hour possible, flood alerts remain in effect.

A Flash Flood Warning was issued for Charleston, South Carolina, where rainfall rates between 1.5 and 2.5 inches are expected. Ongoing or new flooding is expected, with an additional 2 to 4 inches of rain possible over the next few hours.

As onshore flow continues, storm surge remains an issue in Savannah, Georgia, and Charleston, South Carolina. Storm surge alerts remain in effect up the Georgia and Carolina coastlines.

Rainfall aside, Debby could also generate some spin-up tornadoes as it swirls over the Georgia-South Carolina border tonight. As a result, a Tornado Watch also remains in effect for parts of southeastern Georgia and South Carolina until 1 a.m. ET.

Over the next 48 hours, Debby is expected to meander back over the Atlantic but will continue to hug the coastline before heading back inland over the Carolinas again. Slight strengthening can't entirely be ruled out as it moves back over water, but ultimately, Debby is expected to weaken once it moves back inland. Strength aside, it will still bring significant rainfall to portions of the Southeast, which will likely lead to catastrophic flooding in some areas.

Debby is expected to eventually drift toward the north/northeast by the end of the week into the weekend. As it heads north, it will likely weaken to a tropical depression or remnant low. Regardless, heavy rainfall is still expected up the I-95 corridor heading into this weekend.

-ABC News meteorologist Shawnie Caslin Martucci

_{Aug 5, 9:26 PM}

Power returns to some Florida customers as Debby moves northeast

As of Monday evening, 146,034 customers are without power in Florida, according to the latest update from a U.S. power outage map.

This marks an improvement from Monday morning, which saw nearly 300,000 customers without power at 9:50 a.m. ET, the height of outages across the state.

During a press conference in Tallahassee Monday morning, Gov. Ron DeSantis said the state's emergency department had 17,000 linemen working to restore power in the wake of the storm.

"We have a lot of restoration personnel ready to go," DeSantis said.

_{Aug 5, 8:42 PM}

Debby weakening, but threats of tornadoes, heavy rain continue

Tropical Storm Debby continues to weaken, with maximum sustained winds down to 45 mph as of 8 p.m. ET. The weather pattern is moving very slowly to the northeast at 6 mph, and the center is currently about 50 miles east of Valdosta, Georgia.

Even though Debby is now inland and continues to weaken, many of the impacts -- especially the heavy rainfall and dangerous flash flood threat -- will not abate for several days. For many locations in coastal Georgia and South Carolina, the worst is yet to come.

The tornado threat continues along portions of the Georgia and South Carolina coasts this evening and into tonight. A Tornado Watch remains in effect from Savannah, Georgia, to Charleston, South Carolina, until at least 1 a.m. ET.

Parts of Florida, including Sarasota and Lakewood Ranch, are reporting over a foot of rain from Debby, and portions of Suwannee County, including Live Oak, are getting around a foot as well.

So far, parts of Georgia, including Savannah, are reporting nearly 4" of rain. The same can be said for Hilton Head, South Carolina.

Conditions will continue to deteriorate across much of South Carolina overnight Monday into Tuesday, with widespread areas of heavy rain and the potential for dangerous, significant flash flooding during nighttime hours.

Coastal flooding and storm surges will continue to increase in the coming hours as winds increase and more persistent heavy rain moves in, heading into high tide along the Georgia and South Carolina coasts.

By late Tuesday afternoon or early evening, the center of Debby will likely be moving off the Southeast coast and into the Atlantic, where it will meander for about 24 hours before likely turning back toward the coast and potentially making another landfall as a tropical storm somewhere along the South Carolina coast by Thursday morning or afternoon.

-ABC News meteorologist Daniel Peck

_{Aug 5, 7:07 PM}

More than 163,000 customers without power in Florida

More than 163,000 customers are without power in Florida, according to PowerOutage.us , which tracks energy outages.

_{Aug 5, 6:37 PM}

Curfew set for Charleston, South Carolina

A curfew will go into effect overnight for Charleston, South Carolina, due to Debby, city officials said Monday.

Thoroughfares leading into the peninsula will be closed from 11 p.m. ET Monday to noon ET Tuesday, the city said, as the region braces for potential impacts such as tropical storm-force winds, heavy rain and isolated tornadoes.

"We urge everybody to stay inside, stay indoors and do not travel," Charleston Mayor William Cogswell said at a press briefing Monday evening.

_{Aug 5, 5:53 PM}

Biden approves emergency declaration request from South Carolina

President Joe Biden has approved a request from South Carolina Gov. Henry McMaster for an emergency declaration in the state due to Debby, the White House said.

The declaration allows the Federal Emergency Management Agency to mobilize and provide equipment and resources necessary.

"The President continues to urge residents to remain vigilant and heed the warnings of State and local officials," the White House said in a statement.

-ABC News' Cheyenne Haslett

_{Aug 5, 5:47 PM}

North Carolina governor declares state of emergency

North Carolina Gov. Roy Cooper declared a state of emergency ahead of severe weather, including life-threatening flash flooding, expected across the state due to Debby.

"This weather has the potential to bring intense rain and flooding to North Carolina and we are preparing for it," Cooper said in a statement. "As the weather becomes more severe, I urge everyone to take precautions and stay safe."

The emergency declaration will allow for the state to mobilize resources to respond to the storm.

_{Aug 5, 5:30 PM}

Tropical Storm Debby slowing down as it moves across US

Tropical Storm Debby continues to weaken and slow down in forward speed as the center moves near the Florida-Georgia state line as of 5 p.m. ET.

Maximum sustained winds are down to 50 mph, and Debby is moving to the northeast at 6 mph. The center is currently about 30 miles southeast of Valdosta, Georgia.

As of Monday afternoon, all tropical weather and storm surge alerts have been canceled across Florida's Gulf Coast as conditions improve across much of the state.

Debby will move across southeastern Georgia through Monday evening, with the worst impacts focused there and into the Jacksonville, Florida, area. Heavy rain continues to overspread southern South Carolina as well.

-ABC News meteorologist Daniel Peck

_{Aug 5, 4:19 PM}

Latest forecast

Debby is moving inland across north Florida Monday afternoon after dumping more than 1 foot of rain in the state.

Tornadoes are possible Monday night in the coastal cities of Savannah, Georgia, and Charleston, South Carolina.

The biggest concern this week is flash flooding from the widespread, relentless rain. A flash flood emergency remains in effect in Suwannee County, Florida, northwest of Gainesville, where 10 to 15 inches of rain has fallen so far.

Debby will slowly churn into southeastern Georgia throughout Monday afternoon and evening. Through the night, the storm will be focused on Jacksonville, Florida; Savannah; and southern South Carolina.

-ABC News’ Dan Peck

_{Aug 5, 3:58 PM}

More than 1,700 flights canceled

More than 1,700 flights have been canceled within, into or out of the U.S. on Monday, and that number is expected to continue to climb.

American Airlines is seeing the biggest impacts because of its hubs in Miami and Charlotte, North Carolina.

American Airlines said it canceled operations at airports in Gainesville, Sarasota and Tallahassee until noon on Monday.

Sunday was one of the worst air travel days of the year with more than 2,400 cancellations.

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