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ACUS01 KWNS 100101 SWODY1 SPC AC 100059 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0659 PM CST Sat Dec 09 2023 Valid 100100Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL GULF COAST STATES AND TENNESSEE VALLEY... ...SUMMARY... Scattered severe storms capable of producing tornadoes, wind damage and isolated large hail will continue this evening across parts of the central Gulf Coast states and Tennessee Valley. ...Tennessee Valley/Central Gulf Coast States/... The latest water vapor imagery and 500 mb analysis show a progressive upper-level trough over the Ozarks, with a 50 to 06 knot mid-level jet evident in southwesterly flow from the mid Mississippi Valley into the southern Great Lakes. At the surface, a cold front is moving southeastward through the Ohio and Tennessee Valleys. Mosaic radar imagery shows a nearly continuous line of strong to severe thunderstorms ahead of the front from central Kentucky extending southwestward into north-central Mississippi and central Louisiana. These storms are located along the western edge of a weakly to moderately unstable airmass, and near the axis of a 35 to 45 knot low-level jet. RAP forecast soundings this evening, along the axis of the strongest low-level flow, from central Mississippi into far southern Tennessee have 0-3 storm-relative helicity generally in the 200 to 300 m2/s2 range. This will continue to be favorable for rotating storms this evening. As a line of strong to severe storms continues to organize, a few tornadoes will be possible with embedded supercells and bowing line segments. A tornado threat may also exist with discrete rotating cells that develop ahead of the line. As the line progresses eastward, the wind-damage threat will continue, and be maximized with embedded supercells and bowing line segments. An isolated large hail threat will exist with supercells but should be more focused in the southwestern part of the slight where the strongest instability is located. Further south into the central Gulf Coast states, from south-central Mississippi into central Alabama, an isolated severe threat will continue tonight as low-level flow increases ahead of the cold front. Moderate instability is forecast to be maintained ahead of the front as moisture convection continues overnight. As the southern part of the line moves into this area later tonight, the potential for wind damage, hail and a few tornadoes is expected to increase...see MCD 2311. ..Broyles.. 12/10/2023 $$