942 ACUS02 KWNS 140557 SWODY2 SPC AC 140555 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Tue Apr 14 2026 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN PLAINS TO THE MIDDLE MISSISSIPPI VALLEY AND ACROSS EASTERN OHIO INTO PENNSYLVANIA... ...SUMMARY... Severe thunderstorms posing a risk for large hail, strong wind gusts, and a couple of tornadoes will be possible across portions of the southern Plains toward the Great Lakes on Wednesday afternoon and evening. ...Synopsis... A shortwave upper trough will eject from the central Plains to the Great Lakes on Wednesday. A swath of enhanced southwesterly deep-layer flow will extend from the southern/central Plains to the Great Lakes/Midwest ahead of this feature. The southern extent of the upper trough will move more slowly east, from the southern Rockies to the southern High Plains. At the surface, low pressure is forecast to be in the vicinity of the Mid-MO Valley/southeast NE Wednesday morning, and will shift east/northeast along a warm front across IA/southern WI/northern IL through evening. A trailing cold front will move across the Upper Midwest and Great Lakes vicinity during the nighttime hours as the surface low continue to progress northeast into Ontario. Further south, a dryline will extend south/southwest across eastern KS into western OK and west-central TX. A seasonally moist and unstable airmass will be in place ahead of these surface features, focusing severe thunderstorm potential during the afternoon and evening. A warm moist and unstable airmass will extend eastward across portions of the upper Ohio Valley/Northeast. ...MO Valley to Lake Michigan vicinity... Convection is likely to be ongoing across parts of the region Wednesday morning. As a result, uncertainty exists regarding airmass recovery and evolution of severe potential Wednesday afternoon/evening. Persistent southwesterly flow and warm advection ahead of the surface low will maintain a moist airmass. Convection should redevelop by late afternoon/evening near the surface low and along a surface boundary extending from eastern IA to near the IL/WI border. Where heating can occur in the wake of early day convection, MLCAPE around 1000-2000 J/kg should develop. Supercell wind profiles are evident in forecast soundings, especially near the surface low where SRH will be enhanced. Initial cells may pose a risk for hail. Tornado potential is a bit more uncertain given aforementioned concerns about boundary-layer impacts from early day convection. However, at least low potential should exist near the surface low and warm front/outflow. A corridor of higher tornado probabilities may be needed in subsequent outlooks if confidence in mesoscale details and boundary layer recovery increases. During the evening, upscale growth into an eastward-advancing line is expected as a surface cold front begins to move east across the region, and damaging winds will be possible. ...Southern Plains... Isolated supercells are forecast to develop along the dryline in OK into eastern KS/ and eventually portions of MO. Mid to upper 60s F dewpoints beneath steep midlevel lapse rates (7.5-8 C/km) will support 2000-3000 J/kg MLCAPE by afternoon. Some weak capping is noted around 850 mb, which may limit storm coverage in the absence of stronger large-scale ascent. Nevertheless, elongated/straight hodographs above 2-3 km within a favorable thermodynamic environment suggests large to very large hail will be possible with storms that develop. A couple of tornadoes also will be possible given modestly enlarged and favorably curved low-level hodographs and around 150 m2/s2 SRH within a narrow corridor near the dryline. ...Upper Ohio Valley toward the Northeast... Fast deep-layer west/southwesterly flow will overspread a moistening low-level boundary layer. Strong heating will support steepening low-level lapse rates and cool temperatures aloft will support midlevel lapse rates near 7 C/km. This will foster moderate destabilization during the afternoon, promoting isolated to widely scattered thunderstorm development. Damaging wind gusts and isolated hail will be possible with this activity into the evening. ..Leitman.. 04/14/2026 $$