Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
693 ACUS03 KWNS 111910 SWODY3 SPC AC 111909 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0209 PM CDT Sun Oct 11 2026 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL AND SOUTHERN PLAINS... ...SUMMARY... Widely scattered severe storms appear possible over portions of the central and southern High Plains Tuesday afternoon into night. More isolated severe weather may occur into the mid Mississippi Valley, and in parts of the Lower Great Lakes. ...Central/Southern Plains to Mid-MS Valley... Enhanced mid/upper southwesterly flow will reside across the region on Tuesday in advance of an eastward-propagating upper low over the Great Basin to central Rockies vicinity. At the surface, weak lee low development is forecast across southeast CO/southwest KS, with surface troughing extending southward across the southern High Plains. Meanwhile, a surface front will extend from the High Plains low east/northeast across northern KS toward northern IL during the evening. Southerly low-level flow and a strengthening low-level jet will support mid 60s to near 70 F dewpoints across the warm sector from portions of western TX into OK/KS and the Mid-MS Valley. While midlevel lapse rates are not forecast to be particularly strong, rich boundary layer moisture will foster 1000-2000 J/kg MLCAPE. Where stronger heating occurs in closer proximity to the surface trough and triple point from northwest TX into central KS, supercells will be possible amid vertically veering wind profiles. Damaging winds and a tornado or two appear possible within this zone of better instability and shear. Convection is likely to increase along the breadth of the surface front into the Lower MO/Mid-MS Valley as warm advection increases during the evening and overnight hours. This convection may tend to be elevated within isentropic ascent atop the surface front, further supported by boundary-parallel wind profiles. Midlevel temperatures are forecast to be cooler, and MUCAPE could approach 1000-1500 J/kg. Marginal hail and gusty winds may accompany this activity into the nighttime hours. ...Lower Great Lakes... Showers and thunderstorms are likely to be ongoing Tuesday morning ahead of an approaching midlevel shortwave impulse over the Great Lakes. Deep-layer westerlies will increase through the day as this disturbance approaches, resulting in a moderately to strongly sheared environment. If sufficient heating can occur, surface dewpoints near 60 F will aid in modest destabilization, resulting in a conditionally favorable environment for localized strong wind gusts and perhaps a tornado. ..Leitman.. 10/11/2026 $$