The April 2018 North American storm complex brought a wide swath of severe and winter weather that affected much of Midwest across to the East Coast of the United States. This particular outbreak led to at least 73 confirmed tornadoes over a three-day period, most of which occurred across Arkansas and Louisiana during the evening hours of April 13. The most significant tornadoes were an EF1 tornado that caused a fatality in Red Chute, Louisiana, early on April 14, a high-end EF2 tornado that impacted eastern sections of Greensboro, North Carolina on April 15, causing 17 injuries, and a significant EF3 tornado that impacted areas from Lynchburg to Elon, Virginia, causing severe damage and at least 10 injuries.
The system also resulted in a record-breaking and severe blizzard across the Midwest into the Northeastern United States; killing three additional people and leaving hundreds of thousands without power. Snowfall amounts of up to , which are rarely seen in the month of April in the region were observed, shattering numerous records.
Meteorological synopsis April 13–14 On April 8, the Storm Prediction Center (SPC) first introduced a risk of severe weather in their day 6 outlook, valid on April 13. The threat area included the South Plains and the Mid-South from northeastern Texas into southern Missouri, where maturing convection was expected to lead to all modes of severe weather. Subsequent day 5 and day 4 forecasts maintained this area with little deviation. In its day 3 outlook on April 11, the SPC issued an Enhanced risk of severe weather for areas between northeastern Texas into southwestern Missouri, noting that a supercellular storm mode was likely to produce large hail, damaging winds, and a few tornadoes. The Enhanced risk was later extended northward into southern Iowa on April 12, and by the following morning, a Moderate risk was issued across far northeastern Texas and northwestern Louisiana onward into central Arkansas. Several tornadoes, including some strong (EF2+) ones, were expected in the highest risk area. As a result, the outlook included a 15% hatched risk area for tornadoes.
An outbreak of tornadoes unfolded across the region as an expansive upper-level trough pushed into the Central United States, along with a 100kt jet streak pushing into Oklahoma and Missouri. A surface area of low pressure tracked from North-Central Kansas toward the Missouri-Iowa state border, supporting a warm front arced across southern Iowa, and a dryline extending from Kansas into Texas. Within the warm sector of the low, surface dewpoints rose to the mid 60s. A swath of 850mb winds at or above 50kt persisted underneath an elevated mixed layer, yielding an unstable environment characterized by mean-layer Convective Available Potential Energy (CAPE) of 1500–2500 J/kg. Throughout the afternoon, confluent low-level flow caused several discrete thunderstorms to form across Arkansas, where the SPC had issued a Particularly Dangerous Situation (PDS) tornado watch. The most significant supercell of the day developed over LeFlore County, Oklahoma and eventually progressed into Crawford County, Arkansas, where it produced a half-mile-wide EF2 tornado that caused substantial damage in and near Mountainburg.
Into the evening hours of April 13, the low-level jet kept intensified across Arkansas and Louisiana, with 850mb winds topping 60kt. Meanwhile, a cold front pushed eastward and soon overtook the dryline, forcing discrete thunderstorm activity into a quasi-linear convective system. With abundant moisture and mean-layer CAPE still on the order of 1,500–2,000 J/kg, the SPC mentioned potential for swaths of damaging winds with isolated embedded tornadoes. Around 05:10 UTC, an EF1 tornado was developed southwest of Shreveport, Louisiana and progressed directly into the city. It damaged billboards, trees, and hotels before entering Bossier City; there, several mobile homes were damaged and a shopping center was severely devastated. After entering Red Chute, the tornado downed a tree onto a travel trailer, causing one fatality inside. The fatality marked the only tornado-related fatality of the multi-day outbreak. Into the morning hours of April 14, EF2 tornadoes impacted areas near Portland, Arkansas, Carencro, Louisiana, and in Meridian, Mississippi.
April 15 The SPC first mentioned the threat for organized severe weather across the Southeast and Mid-Atlantic regions on April 12, noting that the main threat was expected to be damaging winds. A day 3 Slight risk was outlined for central Florida northward into extreme southern Virginia the next day, with an Enhanced risk of severe weather introduced across much of South Carolina and central North Carolina during the morning hours of April 15. This outlook included a 10% risk area for tornadoes. The potent upper-level trough that sparked severe weather farther west over subsequent days began to tilt in a northwest-to-southeast fashion, forcing rapid cooling aloft and geopotential height falls over a large region. The surface low progressed from Iowa into Ohio and across the Appalachian Mountains, resulting in strong low-level flow and substantial moisture return across the severe weather risk area; dewpoints in the low to mid-60s caused an unstable atmosphere that ultimately led to a quasi-linear convective system and hundreds of damaging wind reports. Embedded semi-discrete supercell structures within this line produced several tornadoes, including EF2 ones that affected areas east of Gilbert, South Carolina and the eastern sections of Greensboro, North Carolina. Another strong tornado moved through the Virginia towns of Timberlake and Lynchburg before reaching EF3 strength as it destroyed several homes in Elon.
Confirmed tornadoes
April 13 event + List of confirmed tornadoes – Friday, April 13, 2018EF#LocationCounty / ParishStateStart Coord.Time (UTC)Path lengthMax width EF2NNE of Rudy to MountainburgCrawfordAR21:04–21:19A multiple-vortex wedge tornado touched down near Rudy and moved north-northeast before tracking into Mountainburg, where significant damage to structures occurred. Along its path, several homes were severely damaged, numerous outbuildings were completely destroyed, power poles were downed, and many trees were snapped or uprooted. Several cars were rolled off Arkansas Highway 282 and Interstate 49. Four people were injured. EF1E of LavacaSebastian, FranklinAR22:46–22:54Trees were uprooted, power poles were snapped, and a mobile home was damaged. EF1N of CalhounOuachitaLA23:34–23:38Numerous trees and power lines were snapped or uprooted. Several houses and barn suffered severe damage, and a mobile home was flipped. EF1E of DownsvilleUnionLA23:43–23:49Many trees were snapped or uprooted. EF1NW of OzoneJohnsonAR23:48–23:54Numerous trees were snapped or uprooted in the Ozark–St. Francis National Forest. A power pole was snapped as well. EF1WNW of SterlingtonUnionLA00:04–00:06A brief tornado snapped or uprooted trees. EF2W of UmpireHowardAR00:10–00:20Many trees were snapped or uprooted by this large multiple-vortex tornado. A metal barn was destroyed, while a second had portions of its tin roof peeled back. Two large chicken houses suffered significant roof damage, and numerous power poles were snapped. EF2Macomb to NNE of NorwoodWrightMO00:13–00:23This tornado touched down in Macomb before moving to the northeast and reaching high-end EF2 strength. A one-story home was destroyed, losing its roof and some exterior walls. Numerous trees were snapped or uprooted, and outbuildings were damaged. EF2WNW of ClarksCaldwellLA00:33–00:43A strong tornado moved through the Catahoula National Wildlife Refuge, snapping and uprooting numerous trees. Several outbuildings and campsites were severely damaged by falling trees, and power poles were snapped. EF1W of DawsonWrightMO00:35–00:40Trees and outbuildings were damaged. EF0W of Pencil BluffMontgomeryAR00:51–00:52Trees were uprooted. EF1SW of SuccessTexasMO01:00–01:02A roof, a carport, and outbuilding were damaged, and trees were snapped. EF1WNW of LickingTexasMO01:20–01:25Numerous trees were snapped or uprooted. A house and a vacant mobile home were damaged. EF1W of GamalielBaxterAR01:45–01:46A church, a garage, and outbuildings sustained damage. Several trees were snapped or uprooted. EF0W of RayvilleRichlandLA02:00–02:06Several large tree branches were broken. EF0SW of OppeloConwayAR02:13–02:14Several trees were snapped or uprooted. EF1WNW of PioneerMorehouse, West CarrollLA02:46–02:50An unoccupied building had portions of its metal roof ripped off, and multiple trees were uprooted or had their branches snapped. EF0SE of El PasoWhiteAR03:13–03:14Some trees were snapped or uprooted, and an outbuilding lost its metal roof. EF1SE of DianaGregg, HarrisonTX04:04–04:13Several trees were snapped or uprooted, one of which landed on a shed. The roof was lifted off a hay storage shed. EF0SSW of Waskom to SE of GreenwoodHarrison, CaddoTX, LA04:50–05:04In Texas, tree limbs were snapped and the roof was blown off a small barn. In Louisiana, the tornado downed power lines and snapped or uprooted trees before dissipating.
April 14 event