ACUS02 KWNS 100602 SWODY2 SPC AC 100600 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Tue Mar 10 2026 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE ARKLATEX AND LOWER MISSISSIPPI VALLEY NORTHEAST THROUGH THE OHIO VALLEY AND MID-ATLANTIC... ...SUMMARY... Isolated to scattered severe thunderstorms are expected on Wednesday from the ArkLaTex and Lower Mississippi Valley northeastward through the Ohio Valley vicinity. ...ArkLaTex to Ohio Valley/Mid-Atlantic... A messy scenario is evident heading into Wednesday from east Texas northeast into PA/MD/VA. A northern stream upper trough will develop east across the Great Lakes/Midwest, while a southern stream shortwave trough moves across TX and the Lower MS Valley. A broad swath of strong southwesterly deep layer flow will overspread these areas, with a particularly strong jet max across the Ohio Valley (80-100 kt at 500 mb). At the surface, a cold front will be oriented from southern Lower MI into central OK Wednesday morning. A dryline/Pacific front will then extend southward across east-central TX. A surface cyclone is expected to deepen as it moves northeast near the international border and Lower Great Lakes through Wednesday evening. As this occurs, the surface cold front will develop southeast, eventually overtaking the TX dryline during the afternoon. This front will become oriented from the Mid-Atlantic coast to the central Gulf coast by Thursday morning. Ahead of the surface boundaries, a broad warm sector will be in place, with surface dewpoints into the 60s F as far north as PA. The strongest instability will likely be focused across the Lower MS Valley where dewpoints into the mid/upper 60s F are possible and at least some stronger surface heating will be possible. With northward extent, instability will decrease, but MLCAPE up to 500-1000 J/kg will be common across the Ohio Valley into VA. One of the main concerns/points of uncertainty precluding higher probabilities across the Ohio Valley vicinity is possible ongoing convection during the morning, and multiple rounds of convection within the broad warm advection regime limiting lapse rates/instability and greater severe potential. Nevertheless, intense deep-layer southwesterly flow will support damaging wind potential across a broad area and an outlook upgrade was considered for parts of southeast OH/northeast KY/southwest PA and western/northern WV. If enough destabilization occurs and a strongly forced line of convection develops, damaging gusts and a few tornadoes could occur. Further south into the ArkLaTex and Lower MS Valley vicinity, a line of convection is expected to be ongoing Wednesday morning. Deep-layer flow will not be as strong compared to further north, but still more than adequate for organized convection. Lapse rates are forecast to remain modest, but linear convection along the surging cold front will pose an all-hazards severe risk. Some forecast guidance suggests discrete convection could develop ahead of the line. If this occurs, some increased risk for tornadoes will develop, especially as storms merge with the line. However, confidence in this scenario is low. Depending on forecast trends, outlook upgrades could become necessary in subsequent outlooks. ..Leitman.. 03/10/2026 $$