Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
962 ACUS02 KWNS 171725 SWODY2 SPC AC 171723 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Mon Jun 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MISSISSIPPI VALLEY TO THE CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe storms will be possible Tuesday afternoon over parts of the Upper Mississippi Valley southwestward into parts of Nebraska and Kansas. ...Synopsis... Highly amplified upper flow will persist over the U.S. Day 2/Tuesday, with a ridge centered over the Mid-Atlantic region, and troughing entrenched over the West. A short-wave trough embedded in the broader-scale cyclonic flow is expected to shift out of the eastern Montana area and across the Dakotas through the period. This progression will be reflected at the surface as a surface cold front advances steadily eastward across the northern Plains, and more slowly southeastward across the Mid-Missouri Valley/Central Plains. Tuesday night, the front should cross the Upper Mississippi Valley and move into the western Upper Great Lakes region. ...Upper Mississippi Valley area southwestward to Kansas... Lingering/overnight convection may be ongoing over the start of the period in the vicinity of Minnesota, but should gradually diminish through the day. Meanwhile, a frontal wave is forecast to shift northeastward through the day from eastern South Dakota across northwestern Minnesota, along an advancing cold front. Daytime heating ahead of the front will drive afternoon destabilization, with 1000 to 2000 J/kg mixed-layer CAPE evolving along the front. This should support storm development from northern Minnesota southwestward to west-central Kansas in the 18/20Z to 18/22Z time frame. While stronger flow aloft will remain displaced to the cool side of the front, amply strong mid-level southwesterlies atop the frontal zone should support shear sufficient for multicell/some supercell organization. Resulting risks for hail/wind support continuation of SLGT risk across this region. Potential should maximize through late afternoon/early evening, before diminishing after dark. ..Goss.. 06/17/2024 $$