Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
432 ACUS02 KWNS 131723 SWODY2 SPC AC 131722 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Wed May 13 2026 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF CENTRAL AND EASTERN KANSAS... ...SUMMARY... Thunderstorms with large hail and severe wind gusts are expected on Thursday across parts of central and eastern Kansas, with more isolated severe storms possible over parts of the lower Missouri Valley, northern Ozarks and southern High Plains. ...Synopsis... Prominent mid-level ridging over the central US is forecast to weaken and shift eastward Thursday as a flanking upper low moves eastward toward the Atlantic Coast. A second upper trough, and associated southern stream shortwave, will move out of the Rockies and into the Plains Thursday afternoon/evening. Ascent from this trough will deepen a lee trough into a surface low over the central High Plains, south of a cold front advancing through the upper Midwest. Strengthening southerly flow ahead of the lee low will allow destabilization and increased thunderstorm chances along a trailing dryline from the central Plains to the southern High Plains. ...Central KS into the MO and central MS Valley... As the southern lee low deepens ahead of the southern stream shortwave trough, a narrow corridor of low-level moisture will quickly return northward into central KS. Model guidance varies considerably on the depth and quality of the low-level moisture. However, dewpoints in the upper 50s to low 60s F appear plausible by late afternoon and continuing to increase into the evening. This, in combination with ascent and steepening mid-level lapse rates, will support moderate destabilization (1500-2500 J/kg MLCAPE) along the dryline/triple point. Low-level southerly flow, veering to 40-50 kt in the mid-levels and orthogonal to the dryline will promote supercell wind profiles. While capping is expected to remain fairly strong, casting some uncertainty on storm coverage, ascent from the approaching shortwave trough along with diurnal heating should remove inhibition. Convective development is possible near the surface low, or originating within the more deeply mixed air mass to the west of the dryline, by late afternoon/early evening. Large hail would be likely initially, along with some potential for severe wind gusts given the dry boundary layer. As these storms encounter the increasing surface moisture, gradual intensification of a few supercells is possible. The increase in the low-level jet after 00z could support additional development, while also increasing low-level shear. A tornado is possible with any supercells able to remain discrete near sunset given 0-1 km SRH of 200-400 m2/s2. Eventually, storms should congeal into a cluster and spread eastward into MO and the mid MS Valley overnight. Some hail and damaging gust threat remain possible into early D3/Friday. ...Southern and central High Plains... To the west of the dryline, robust heating and deep vertical mixing should support the development of weak instability atop a relatively dry boundary layer. By mid afternoon, high-based showers and thunderstorms are expected from eastern CO, western KS into parts of the OK/TX Panhandles and eastern NM. While buoyancy appears quite limited (~500 J/kg MUCAPE), nearly dry adiabatic lapse rates in the lowest 3 km will likely support stronger downdrafts with scattered showers/thunderstorms. Isolated severe wind gusts are possible given the dry sub cloud layer. ..Lyons.. 05/13/2026 $$