Between April 2–3, 2017, the Deep South was impacted by a deadly springtime tornado outbreak. 62 confirmed tornadoes touched down in this period. Three fatalities occurred during the outbreak; one as a result of an EF1 tornado in Whitmire, South Carolina, and two after an EF1 tornado touched down near Breaux Bridge, Louisiana. The outbreak was one of the strongest to affect Louisiana since 1950, with 21 tornadoes touching down there. In Louisiana alone, over $4 million dollars in damages was sustained. The outbreak saw the second High Risk day of 2017 and caused widespread power outages in Georgia. The strongest tornadoes of the outbreak were eight EF2 tornadoes, many of which caused structural damage to communities in Louisiana, Georgia and South Carolina.
Meteorological synopsis
April 2
On April 2, 2017, a rare and volatile high shear/high CAPE atmospheric setup developed across the Deep South. Strong southerly winds, driven by an elongated jet streak pattern, enhanced low-level wind shear and transported rich Gulf moisture northward, causing dew points to rise rapidly.
At the same time, a large upper-level trough was positioned over Texas and Louisiana. As the day progressed, the trough took on a negative tilt, increasing large-scale lift and further strengthening wind shear. At the surface, an inverted trough over East Texas supported a strengthening low-pressure system that became increasingly meridional in structure. Across central Louisiana, mixed-layer CAPE (MLCAPE) values reached approximately 1500–2000 J/kg, while deep-layer wind shear ranged from 20–30 m/s.
These conditions led to the issuance of a High Risk (the most severe outlook category) by the Storm Prediction Center. The zone covered parts of Texas and Louisiana, marking the first time since 2005 that the latter had been placed under a High Risk designation. Several potentially dangerous tornadoes were forecast, and at around 9:00 AM CDT, the first tornadoes of the outbreak began to touch down in Louisiana.
April 3
The next day, on April 3, a fast-moving line of severe thunderstorms developed ahead of an advancing cold front and swept rapidly eastward across the southeastern United States. This line evolved into a quasi-linear convective system (QLCS), with strong wind shear already in place ahead of it.
As the system progressed, favorable low-level shear in the form of elevated storm-relative helicity (SRH) supported the development of numerous tornadoes along the leading edge of the line. These tornadoes were primarily embedded within the QLCS structure and formed quickly as the storms advanced into Georgia by mid-morning.
Initially, a severe thunderstorm watch was issued as the line of storms approached Georgia. As the tornado threat became more apparent, the Storm Prediction Center upgraded portions of the region to a tornado watch that covered parts of Georgia and South Carolina during the afternoon hours.
Confirmed tornadoes
April 2 event
+ List of confirmed tornadoes – Sunday, April 2, 2017EF#LocationCounty / ParishStateStart Coord.Time (UTC)Path lengthMax widthSummary EF1S of LafayetteLafayetteLA14:04–14:05A brief, small tornado was caught on security video lifting and overturning a car in the lot of a car body shop. Two pieces of tin were removed from the shop roof. EF0LakewayTravisTX14:15–14:18Several marinas were damaged as a small tornado crossed Lake Travis. Trees were damaged. EF1E of Breaux BridgeSt. MartinLA14:47–14:492 deaths – A single-wide mobile home was rolled, separating the roofs and walls from the structure and killing two occupants. EF0SW of RiversideWalkerTX17:25–17:27A barn was lifted and deposited across a road, and trees were damaged. EF1BroaddusSan AugustineTX18:56–19:06A waterspout moved ashore, snapping and uprooting dozens of trees along its path and striking the town of Broaddus. A covered canopy between a church and another building in town collapsed. EF1SW of AlexandriaRapidesLA19:32–19:46A few pine trees were snapped. EF2W of WoodworthRapidesLA19:50–19:59A large swath of trees was completely flattened in the Kisatchie National Forest. Falling trees also caused damage to four homes. EF2NE of Fishville to SW of JenaLaSalleLA19:53–20:04Several outbuildings lost siding, or sustained roof damage as a result of this large wedge tornado. An oil derrick was toppled over, with the metal severely bent, and a concrete anchor block was pulled out of the ground. A second rusty oil derrick was not only collapsed but broken into pieces as well. EF1Western AlexandriaRapidesLA20:05–20:18This tornado moved through the western part of Alexandria, damaging numerous structures. A gas station awning was damaged, the side and doors of a large storage building were blown in, and numerous trees were snapped or downed. Some trees landed on homes, garages, and vehicles. Structures sustained minor roof damage to their shingles or soffit, while flat roofs were partially lifted off businesses. Flying debris broke windows, large billboards, and other signage. EF1SSW of FlorienSabineLA20:07–20:23Numerous trees were snapped or uprooted, much of the roof was ripped off a double-wide manufactured home, and an outbuilding was destroyed. EF0W of LenaRapidesLA20:20–20:21Storm chasers drove through a brief tornado which caused no significant damage. EF2E of Fishville to TroutLaSalleLA20:52–21:12A very large mile-wide wedge tornado hit the communities of Belah and Trout, causing considerable damage. Widespread damage occurred in Belah, with damage to the roofs of homes and a school building. Outbuildings were damaged or destroyed, many were trees blown over onto structures and vehicles, a metal truss tower was toppled over, and several power poles were broken into multiple pieces in the Belah area as well. In Trout, homes and trees sustained damage, while a boat business collapsed. Large swaths of heavily forested areas were completely flattened along the path, with every tree in the path snapped or uprooted in some areas. EF1W of GeorgetownGrant, WinnLA20:54–20:57A large wedge tornado moved through the Kisatchie National Forest, snapping and uprooting trees along its path. EF1NE of MontgomeryGrant, WinnLA21:12–21:23Numerous trees were snapped or uprooted, a truck and an RV were destroyed by fallen trees, and a house sustained roof damage. Several outbuildings were damaged, rolled, or destroyed. EF1ESE of Columbia to WSW of BaskinCaldwell, Franklin, RichlandLA21:17–21:46This large wedge tornado snapped and uprooted many trees, and ripped tin roofing off of a house. EF2N of MidwayLaSalleLA21:18–21:20Several homes sustained damage, mainly due to flying debris and falling trees, including a mobile home that was almost completely destroyed by falling trees. One well-constructed residence has its carport collapse atop two vehicles, while a second home was shifted 10 feet off of its pier and beam foundation. A third well-built brick home lost its roof entirely, and numerous power poles and trees were snapped. EF2NE of Jena to NNW of HarrisonburgLaSalle, CatahoulaLA21:22–21:42This tornado struck the community of Aimwell. A few homes sustained roof damage, outbuildings were destroyed, a brick church sustained damage to its roof and walls, numerous large trees and many power poles were snapped, and a mobile home was flipped. Another mobile home lost its awning as well. One person was injured. EF1SW of ManghamRichlandLA21:48–21:53A metal building was damaged, a fence was flattened, and numerous trees were snapped or uprooted. A home and a shed sustained minor roof damage. EF1NW of BaskinRichland, FranklinLA21:49–21:59A power pole and several trees were snapped. One mobile home was destroyed while a second had its shingles ripped off. EF2SE of WinnsboroFranklinLA22:09–22:22Numerous trees were snapped, power poles were broken, a small trailer was tossed, and a shed and a residence sustained minor roof damage. One small home built on blocks was completely destroyed, a horse trailer was flipped, and a mobile home was tossed . EF0NE of GilbertTensas, MadisonLA22:41–22:44A few trees and limbs were snapped. EF1W of Brookhaven to SSE of WessonFranklin, LincolnMS05:57–06:22Trees were snapped or uprooted. Barns, mobile homes, and houses sustained minor roof or siding damage. At least six utility poles were snapped.
April 3 event