Three people were killed in Mississippi and Alabama by a severe storm that roared through the Deep South and is expected to intensify from Florida to the Mid-Atlantic states as it hits the East Coast.

"The most likely area for tornadoes may be close to the Carolina coast, where a breeze from the Atlantic Ocean may impart extra spin in the low levels of the atmosphere," according to AccuWeather Senior Meteorologist Dan Kottlowski.

The storm began pummeling Georgia by Friday morning rush hour, snarling traffic and causing 63 flight delays at Hartsfield-Jackson Atlanta International Airport, according to Flightaware.com. One power pole came down on West Peachtree in Midtown Atlanta, causing a massive backup of traffic.

The three-day storm has left more than 120,000 households without power across four states, including 20,000 knocked out Friday morning in Georgia.

A Mississippi man was killed Thursday afternoon when his car hit a tree on a highway south of Philadelphia, Mississippi, Neshoba County Coroner John Stephens told local news outlets. Another man was also killed while when his 18-wheeler slammed into a tree near the rural town of Gillsburg in southwest Mississippi, WJTV reported.

In Alabama, a woman died when a tree fell on her mobile home in St. Clair County, according to the local sheriff's office. The woman's 10-year-old son suffered minor injuries.

Multiple tornadoes and storms swept across parts of Mississippi on Thursday afternoon and evening, leaving downed trees and tens of thousands of households without power.

Damage from the storm system was reported in at least 24 of Mississippi’s 82 counties.

In northeast Mississippi, Scott County Emergency Management Director Mike Marlow said reports indicated a number of homes were damaged near Morton and the roof blew off a gas station near Lena. In Philadelphia, Mississippi, a wall collapsed at a medical clinic and the storm knocked down traffic signals and canopies and pushed trees onto houses, the Neshoba Democrat reported.

In Hinds county, loggers were brought in to extract a school bus that was trapped between two trees. The driver and students were unharmed.

There were widespread power outages also reported in Alabama, Louisiana and Texas on Thursday night.

Alissa Zhu reports for Mississippi Clarion Ledger.

Contributing: The Associated Press