Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
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287 ACUS01 KWNS 120545 SWODY1 SPC AC 120543 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 $$