UPDATE: Tropical Storm Nestor continues pounding parts of the Florida Gulf Coast with heavy rain, strong winds and storm surges Saturday, the National Hurricane Center said.

At 5 a.m. ET, Nestor's winds were 50 mph, down from maximum sustained winds of 60 mph Friday evening.

Nestor is expected to move inland over the Florida Panhandle on Saturday morning, the hurricane center said.

Tornado watch issued

"The growing threat this morning is for tornadoes. A tornado watch has been issued for parts of north and central Florida until noon ET," said CNN Meteorologist Allison Chinchar.

"The National Weather Service already confirms potential tornado damage in Polk County. This threat will spread into other states such as Georgia, North Carolina and South Carolina as we go through the day."

One tornado has already caused a tractor trailer "to overturn" onto another vehicle on Interstate-4 in Polk County, according to Florida Highway Patrol Sergeant Steve Gaskins.

Debris from the impact then struck two other cars, both those vehicles were able to come to a "controlled stop," a FHP press release said.

Westbound Interstate 4 lanes were closed following the accident at 11 p.m. ET Friday and remained so until 1:30 a.m. Saturday. No injuries were reported, the release said.

Widespread rainfall totals of 2 to 4 niches are expected, with isolated totals of 6 inches possible. Flash floods are also possible across the Southeast into Sunday morning.

The rain could be good news for inland residents who endured a dry and hot September. Alabama, Florida, Georgia and Mississippi all had their driest September on record.

Many areas across the region have experienced a flash drought due to the prolonged heat and dry conditions. Areas that weren't in any type of drought in August are now in severe to extreme drought.

Storm surges possible

Storm surge values have ranged from 2 to 3 three feet Saturday morning along the Big Bend region.

"There is a danger of life-threatening storm surge inundation of up to 5 feet about ground level along the Florida Gulf Coast from Indian Pass to Clearwater Beach, where a storm surge warning is in effect," the hurricane center said. "Residents in these areas should follow advice given by local officials."

The tornado watch that has been issued for central and northern Florida means conditions are favorable for tornadoes to form.

Higher concerns through the morning hours will be focused on tornadoes causing damage and heavy rain, which could lead to flooding inland through central and northern Florida and into southern Georgia.

PREVIOUS STORY: The first bands of Tropical Storm Nestor are beginning to affect the Gulf Coast, the National Hurricane Center said Friday afternoon.

The system gained tropical storm status and had maximum sustained winds of 60 miles per hour.

Winds, rain and storm surge will be increasing Friday afternoon and evening, with the center of Nestor expected to make landfall around daybreak Saturday near Panama City in the Florida Panhandle.

Warnings have been issued for parts of coastal Louisiana, Alabama and Florida. Dangerous storm surge, strong winds and heavy rain are expected.

In anticipation of strong winds, New Orleans officials Friday plan to blow up two cranes that have been in a precarious position since a Hard Rock Hotel construction site collapse that killed two people over the weekend. The intentional explosions are meant to bring the cranes down safely before winds get perilously strong.

Storm surge is a major concern for Florida

The storm system was over the Gulf of Mexico on Friday afternoon, about 355 miles southwest of Panama City. with sustained winds near 60 mph. Its outer edges earlier brought heavy rain to portions of southern Mexico.

As the system approaches Florida, it could bring a dangerous storm surge of 2 to 5 feet to a large portion of Florida's Gulf Coast, from Indian Pass near the Big Bend region south to Clearwater Beach, forecasters say.

Surges of 1 to 3 feet were possible in Tampa Bay, the hurricane center said.

"This is a life-threatening situation," the hurricane center said Friday morning. "Persons located within these (storm surge warning) areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions."

Winds and rain

Tropical-storm-force winds of 39 mph and higher are expected Friday in the tropical storm warning areas.

Forecast models show the storm could move into parts of Georgia and the Carolinas on Saturday and Sunday. Winds of similar strength are possible there, the hurricane center said.

The storm is expected to drop 2 to 6 inches of rain over the weekend in the central Gulf Coast, northern and central Florida, and parts of Georgia and the Carolinas, forecasters say.