A line of thunderstorms ahead of an approaching cold front started developing and intensifying in the mid to late afternoon hours across northern Georgia and Alabama. There were also discrete supercells developing ahead of the main line during peak heating. The line approached the western part of the forecast area around 9 pm as the line was beginning to interact and consolidate with the discrete cells out ahead of it. The line swept across the entire forecast area with numerous reports of wind damage and a smaller collection of large hail. The near storm environment was marked by impressive mid levels with 500-700 mb lapse rates less than -7 C/km and LI's as low as -3 to -4 C. The presence of an elevated mixed layer resulted in DCAPE values in the 800-1000 J/kg range. The upstream convective line was forced by strong ambient shear (on the order of 50-60 kts in the 0-6 km layer) with adequate surface based instability (CAPE in the 500-750 J/kg range). The supercell elements upstream yielded a tornado threat which subsequently diminished into the forecast area with less instability present and a convective mode favoring linear segments.  The Storm Prediction Center hoisted a Severe Thunderstorm Watch around 7:30 pm for all of southeast Georgia and the portion of South Carolina that bordered the Savannah river. The line not only maintained its strength but intensified with base velocities upwards of 70 knots at times as it entered the area.

Hail in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 20:59:00 to 18-MAR-13 21:00:00 (EST-5)
Location: SCOTIA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported quarter size hail in Scotia, South Carolina.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:08:00 to 18-MAR-13 21:09:00 (EST-5)
Location: GIFFORD
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down on Luray Highway near Hope Well Road.

Thunderstorm Wind in ALLENDALE, SOUTH CAROLINA
From 18-MAR-13 21:10:00 to 18-MAR-13 21:11:00 (EST-5)
Location: ALLENDALE CO ARPT
Magnitude: 50.00 EG
Property damage: 2.25K
Crop damage: 0.00K
Reported by: Emergency Manager

An emergency manager reported a tree down on two power lines.

Thunderstorm Wind in DORCHESTER, SOUTH CAROLINA
From 18-MAR-13 21:36:00 to 18-MAR-13 21:37:00 (EST-5)
Location: ROSINVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down on Highway 15 between Interstate 26 and Highway 178.

Thunderstorm Wind in JASPER, SOUTH CAROLINA
From 18-MAR-13 21:36:00 to 18-MAR-13 21:37:00 (EST-5)
Location: GILMANIA
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Jasper County 911 Call Center reported a tree down near Coolers Grocery on Coosaw Scenic Drive.

Thunderstorm Wind in COLLETON, SOUTH CAROLINA
From 18-MAR-13 21:46:00 to 18-MAR-13 21:47:00 (EST-5)
Location: WHITEHALL
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Colleton County 911 Call Center reported a tree down between the 4000 and 5000 block of Combahee Road.

Thunderstorm Wind in JASPER, SOUTH CAROLINA
From 18-MAR-13 21:38:00 to 18-MAR-13 21:39:00 (EST-5)
Location: LEVY
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down in the 3700 block of Bellinger Hill Road.

Hail in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:17:00 to 18-MAR-13 21:18:00 (EST-5)
Location: NIXVILLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public reported hail slightly larger than quarters near the intersection of Turner Expressway and Highway 3.

Hail in BEAUFORT, SOUTH CAROLINA
From 18-MAR-13 22:01:00 to 18-MAR-13 22:02:00 (EST-5)
Location: WADDELL GARDENS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter reported quarter size hail.

Thunderstorm Wind in COLLETON, SOUTH CAROLINA
From 18-MAR-13 21:40:00 to 18-MAR-13 21:41:00 (EST-5)
Location: JONESVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down near the intersection of Lowcountry Highway and Highway 17A.

Thunderstorm Wind in COLLETON, SOUTH CAROLINA
From 18-MAR-13 21:48:00 to 18-MAR-13 21:49:00 (EST-5)
Location: HENDERSONVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down on Hendersonville Highway about 2 miles south of Hendersonville, South Carolina.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:12:00 to 18-MAR-13 21:13:00 (EST-5)
Location: BRUNSON
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down on Tinker Town Road near Highway 278.

Thunderstorm Wind in ALLENDALE, SOUTH CAROLINA
From 18-MAR-13 21:15:00 to 18-MAR-13 21:16:00 (EST-5)
Location: FAIRFAX
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Emergency Manager

An emergency manager reported a tree down on Aiken Avenue South.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:25:00 to 18-MAR-13 21:26:00 (EST-5)
Location: CUMMINGS
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down near the intersection of Edward Mixon Road and Highway 68.

Thunderstorm Wind in DORCHESTER, SOUTH CAROLINA
From 18-MAR-13 21:41:00 to 18-MAR-13 21:42:00 (EST-5)
Location: ST GEORGE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The Dorchester County 911 Call Center reported a tree down on Dukes Street.

Thunderstorm Wind in DORCHESTER, SOUTH CAROLINA
From 18-MAR-13 22:14:00 to 18-MAR-13 22:15:00 (EST-5)
Location: KNIGHTSVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Amateur Radio

A tree was reported down at the 1100 block of Orangeburg Road.

Thunderstorm Wind in ALLENDALE, SOUTH CAROLINA
From 18-MAR-13 20:59:00 to 18-MAR-13 21:00:00 (EST-5)
Location: ALLENDALE OSWALD ARP
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Emergency Manager

An emergency manager reported a tree down near the intersection of River Road and Chess Loop.

Thunderstorm Wind in ALLENDALE, SOUTH CAROLINA
From 18-MAR-13 21:05:00 to 18-MAR-13 21:06:00 (EST-5)
Location: ALLENDALE
Magnitude: 50.00 EG
Property damage: 2.25K
Crop damage: 0.00K
Reported by: Emergency Manager

An emergency manager reported a tree down on a mobile home.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:25:00 to 18-MAR-13 21:26:00 (EST-5)
Location: VARNVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down near the intersection of Highway 68 and Highway 278.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:17:00 to 18-MAR-13 21:18:00 (EST-5)
Location: NIXVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down near the intersection of Hope Well Road and Two Sisters Ferry Road.

Thunderstorm Wind in DORCHESTER, SOUTH CAROLINA
From 18-MAR-13 22:00:00 to 18-MAR-13 22:01:00 (EST-5)
Location: RIDGEVILLE
Magnitude: 50.00 EG
Property damage: 1.25K
Crop damage: 0.00K
Reported by: Amateur Radio

A power line was reported down at the 1200 block of Ridge Road.

Thunderstorm Wind in ALLENDALE, SOUTH CAROLINA
From 18-MAR-13 21:05:00 to 18-MAR-13 21:06:00 (EST-5)
Location: ALLENDALE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Emergency Manager

An emergency manager reported a tree down near the intersection of Barton Street and Flat Street.

Thunderstorm Wind in HAMPTON, SOUTH CAROLINA
From 18-MAR-13 21:25:00 to 18-MAR-13 21:26:00 (EST-5)
Location: CUMMINGS
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The South Carolina Highway Patrol reported a tree down near the intersection of Highway 278 and Rock Spring Road.