562 ACUS02 KWNS 231752 SWODY2 SPC AC 231715 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK Issued by 15th OWS Scott Air Force Base IL 1215 PM CDT Thu Apr 23 2026 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible Friday from the Southern Plains into the Lower Mississippi Valley. Large hail and damaging winds will be the main hazards, with a brief tornado also possible. Isolated strong wind gusts may occur across portions of the lower Ohio Valley as well. ... Synopsis ... Broad cyclonic flow will persist across much of the central and western US as a longwave trough remains anchored over the northern states. In the absences of stronger large-scale ascent across the southern US, convective evolution will be driven primarily by remnant boundaries and subtle perturbations within the broader cyclonic flow. ... Southern Plains into the Lower Mississippi Valley ... Convection is expected to be ongoing from portions of Oklahoma into Arkansas and Missouri at the start of the forecast period, largely tied to a convectively augmented cold front. This activity may still be capable of producing isolated strong wind gusts early in the period, but should gradually weaken through the morning as the low-level jet dissipates and the parent shortwave trough moves away from the region. The primary severe threat is expected to develop from the afternoon into the evening along the effective frontal zone and any residual outflow or differential heating boundaries. Current guidance suggests the boundary will settle near or south of the I-40 corridor, though some uncertainty in the exact location remains. Notably, the HRRR is an outlier in maintaining a farther north and west boundary as compared to other members of the 20260423/Z HREF. By afternoon, strong heating south of the boundary will support a moderately to strongly unstable airmass (SBCAPE values in the 2000-3000 J/kg range) from central/east Texas northward toward the boundary, with instability gradually decreasing with eastward extent into Mississippi and Alabama. Deep-layer shear will remain modest across the region (generally 30-35 knots), supporting organized multicells and occasional transient supercells. Thunderstorms should develop/intensify from eastern Oklahoma into Arkansas along one or more of boundaries across the region. Initial storms may pose a threat for large hail and localized damaging wind gusts as low-level shear will generally remain weak. However, localized enhancements along boundaries or any MCV could support a brief tornado risk. With time, storm interactions and consolidating outflows should support upscale growth into one or more clusters or linear MCS structures. These systems should move east-southeast into northern Louisiana and central Mississippi through the afternoon and evening hours. While the modest deep-layer shear may temper the overall wind threat somewhat, sufficient organization should still support a corridor of damaging wind gusts. Farther west into central and eastern Texas, isolated convection may occur along a dryline as diurnal heating weakens inhibition to the east. Storm coverage is expected to remain sparse given weak ascent, but any sustained updrafts in this strongly unstable environment could produce large hail. ... Portions of the Ohio Valley ... A separate corridor of thunderstorms may develop during the afternoon across portions of the eastern Indiana and western Ohio in the wake of earlier convection. Modest destabilization should occur with perhaps up to 1000 J/kg of SBCAPE. Although the low-level jet will be weakening through the day, residual flow and modest deep-layer shear may support loosely organized convection capable of producing damaging wind gusts. ..Afwa.. 04/23/2026 $$