NEW IBERIA, La. - Powerful storms that killed at least two people and ripped apart mobile homes in Louisiana headed into Alabama on Friday, where tornado watches were posted across the state.

A flash-flood watch was still in effect Friday morning for parts of southeast Louisiana and southern Mississippi after the heavy rain.

Some of the worst damage from Thursday's storms was in Louisiana's Iberia Parish after what appeared to be a tornado hit in the New Iberia area just before 4 p.m.

A woman and six-year-old girl were killed in their home as the storm hit, the Iberia Parish Coroner's Office said. At least 15 other people were injured, and several mobiles homes were blown over, Sheriff Sid Hebert said.

"We were just sitting and watching a movie, and then all of a sudden the wind started blowing and it got really bad," said Joyce Firmin of Iberia Parish. "It just sounded like a bunch of trucks or an airplane or something was coming toward the house."

Firmin's daughter Jaci, 14, said she could hear branches snapping and power lines popping during the storm. "My ears were popping a lot," she said. "Then we came out, everything was down."

Steven Bruno described from a hospital how he was flipped over twice while furniture and glass flew around his mobile home. His girlfriend, who is six months pregnant, was hospitalized for fetal monitoring.

Whether it was a tornado won't be determined until storm surveys are conducted.

Damage was less serious as the storm continued through the state, although the heavy rain flooded roads, and windows were blown out and roofs ripped off homes in the New Roads area, National Weather Service meteorologist Jim Vasilj said.

In Mississippi, at least nine people were hurt in Kemper County and eight homes damaged when the storm hit there late Thursday and early Friday, according to the Mississippi Emergency Management Agency. Five more homes and business were damaged in Stone County.

City workers in New Orleans had been dispatched early to clean drains and prepare for possible flooding ahead of the heavy rain.

The area has been pounded by major storms that bumped its December rainfall total to more than 25 centimetres, nearly twice the normal average.

Forecasters on Friday warned that more rain was coming.

"More showers and thunderstorms are on the way Saturday afternoon and evening as we get another cold front coming through. We're in a progressive pattern - almost like clockwork, every three days we'll get a front through," said weather service forecaster Kent Kuyper.