On April 22, 2020, an outbreak of discrete supercell thunderstorms across portions of Oklahoma, Texas, and Louisiana led to widespread severe weather, including multiple strong tornadoes. Two people were killed by a high-end EF2 that struck the town of Madill, Oklahoma, and three more were killed by an EF3 wedge tornado that moved through Onalaska, Texas. Dozens of others were injured as well. The event came to fruition as a trough progressed eastward across the United States, interacting with a moist and unstable environment. Tornado activity continued into Arkansas, Louisiana, Mississippi, Alabama, Florida, and Georgia overnight into the day on April 23. Isolated tornado activity also occurred during the overnight hours on April 21.

Meteorological synopsis On April 19, the Storm Prediction Center outlined portions of the U.S. Southern Plains with a 15% area of severe weather within 25 miles of any point. A Slight risk was maintained across much of the same areas in the subsequent day 3 outlook, but parts of southeastern Oklahoma, much of northeastern Texas, southwestern Arkansas, and northwestern Louisiana were upgraded to an Enhanced risk on April 21. This risk area was maintained in the lead-up to the event on April 22. Confidence in organized severe weather came as a southwest-to-northeast oriented trough moved eastward across the United States, interacting with a corridor of low-level moisture and instability ahead of this feature. Throughout the early morning hours of April 22, discrete thunderstorms posing a risk for damaging winds and hail developed across Oklahoma, north of an approaching warm front. Farther south across central Texas and into western Louisiana, elevated convection began to increase in the presence of strong wind shear, with the expectation that those storms would become surface based with time as they progressed into a region of modest daytime heating.

Isolated tornadic activity was observed in Oklahoma during the overnight hours of April 21. By mid-afternoon the next day, a low-pressure area progressed into southwestern Oklahoma, supporting a quasi-stationary front across southern Oklahoma and a sharpening dry line southward into central Texas. The combination of partially sunny skies and dew points in the upper 60s Fahrenheit led to a very unstable environment across northwestern Texas and into southwestern Oklahoma. Thunderstorm activity soon developed in the vicinity of the area of low pressure, but the highest risk of tornadic activity was expected to materialize farther east where the direction of surface winds would be more conducive to rotating storms. As the storms tracked eastward, multiple damaging tornadoes were reported. Farther south across eastern Texas and western Louisiana, a subtle warm front and an additional surface boundary proved to be the impetus for convection to develop supercell characteristics. One such supercell in Walker and Houston counties further organized as it curved right into an undisturbed environment of high wind shear and moisture. Within the hour, it spawned an intense, long-tracked tornado with winds of as estimated by the SPC based on historical analogs. This long-tracked cell maintained prominence and spawned additional tornadoes for several hours as it continued through Louisiana and into Western Mississippi. On its trail, additional storms in a moderately unstable, highly sheared environment continued to pose a threat for all hazards. Severe weather from this group of storms continued throughout the overnight hours along the Gulf Coast, with large swath of wind damage and tornadoes continuing into April 23. More storms fired up just offshore of the Florida panhandle as the first band moved off the coast around mid-day. These storms produced more tornadoes and wind damage before weakening that night.

Confirmed tornadoes

April 21 event + List of confirmed tornadoes – Tuesday, April 21, 2020EF#LocationCounty / ParishStateStart Coord.Time (UTC)Path lengthMax width EF1SE of SterlingComanche, GradyOK04:28–04:30A mobile home was heavily damaged. EF1Northern MarlowStephensOK04:43–04:46A tornado impacted northern sections of Marlow, severely damaging several buildings on a farm, including a home and an outbuilding that had most of their roofs ripped off. Large trees were broken or damaged, and utility poles were snapped as well.

April 22 event + List of confirmed tornadoes – Wednesday, April 22, 2020EF#LocationCounty / ParishStateStart Coord.Time (UTC)Path lengthMax width EF1SW of Pauls ValleyGarvinOK 21:17–21:22Trees, power poles, a few outbuildings, and seven homes were damaged. EF0N of SpringerCarterOK 21:23A very brief tornado lofted some debris. EF2NE of SpringerCarter, MurrayOK 21:24–21:37A strong tornado moved through an unpopulated wooded area, causing significant tree damage. EFUSW of MadillMarshallOK21:45A brief tornado touched down, causing no damage. EF2SSW of Oakland to SE of MadillMarshallOK 21:53–22:052 deaths – This high-end EF2 tornado, which was videoed by numerous storm chasers and broadcast live on The Weather Channel, moved through the southern part of Madill. Three factories or warehouses–Oklahoma Steel & Wire, Mid American Steel & Wire, and M & R Wire Works–sustained significant damage, and a catholic church sustained considerable roof and window damage. Several site-built homes sustained roof damage, and one had its roof removed entirely. Multiple mobile homes, barns, and outbuildings were destroyed, several vehicles were damaged or thrown, and a satellite dish was ripped off a 310-foot guyed radio tower. Many wooden and steel power poles were snapped or knocked down, and many trees were downed along the path as well. At least 30 people were injured. EF0SW of Little CityMarshallOK 22:10–22:14A power pole and some trees were damaged. EF1N of WapanuckaJohnstonOK 22:26–22:38Trees and roofs sustained damage, and an RV camper was overturned. EF1N of ArmstrongBryanOK 22:32–22:45A number of homes, barns, and trees were damaged by this multiple-vortex tornado. Power poles were downed as well. EF1E of ArmstrongBryanOK 22:52–22:53A number of tree branches were broken, and a building was damaged. EF3NW of Onalaska to WSW of ChesterTrinity, PolkTX22:35–23:153 deaths – See section on this tornado – 33 people were injured. EF0SW of LehighCoalOK22:59Two separate storm chasers videoed a tornado; it caused no damage. EF1N of TocoLamarTX23:35–23:42A few outbuildings were damaged or destroyed near the community of Direct. Trees were also damaged. EF2ENE of PowderlyLamar, Red RiverTX23:51–00:05Numerous large trees were snapped or uprooted, and a handful of homes sustained relatively minor roof damage. EF2E of Jasper, TX to N of Rosepine, LAJasper (TX), Newton (TX), Vernon (LA)TX, LA00:28–01:19A long-tracked, strong tornado produced by the same supercell as the Onalaska EF3 tornado damaged roofs and trees. Severe tree damage occurred in some areas, including a few trees that sustained some debarking. EF2ElmerRapidesLA02:09–02:27A few homes and power poles were damaged, and many trees were snapped in and around Elmer. Some trees sustained debarking. EF2S of AlexandriaRapidesLA02:26–02:381 death – Two mobile homes were demolished, resulting in one fatality. Numerous houses and trees were damaged, and numerous power poles were toppled. Substantial damage was inflicted to a livestock facility, and severe damage was also inflicted to farm and equipment buildings at the LSU-Alexandria Dean Lee Research Station. EF1LamourieRapidesLA02:27–02:34Outbuildings and sheds were damaged, power lines were snapped, and shingles were ripped off a roof. EF1N of Ruby to NW of EffieRapides, AvoyellesLA02:42–02:53A tornado caused considerable tree damage, some of which damaged a few homes upon falling. EF1NE of MarksvilleCatahoula, AvoyellesLA 03:06–03:18Trees and mobile homes were damaged. EF1NW of AcmeCatahoula, ConcordiaLA 03:17–03:25Numerous trees were snapped, and a mobile home lost sections of its roof, siding, and metal awning.

April 23 event