Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
362 ACUS03 KWNS 270829 SWODY3 SPC AC 270828 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CST Thu Nov 27 2025 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE TEXAS COASTAL PLAIN TO THE SABINE RIVER VALLEY... ...SUMMARY... Isolated severe thunderstorms are possible across portions of southeast Texas into northern Louisiana Saturday afternoon or evening. ...Synopsis... A surface low will translate northeast from the southern Plains toward the Great lakes as a broad mid-level trough overspreads the central U.S. on Saturday. Relatively rich low-level moisture return will occur across the Sabine River Valley ahead of a surface cold front. Isolated to scattered thunderstorm development should occur within a warm-air advection regime. Given strong vertical wind shear in place due to a departing low-level jet, isolated strong to severe storms are possible across the TX Coastal Plain toward the Sabine River Valley ahead of the approaching cold front. ...Southeast Texas into northern Louisiana... Scattered showers and thunderstorms will be ongoing across the southern Plains into the Lower MS Valley within the warm-air advection regime. Through the day, airmass modification will result in some boundary layer destabilization as cloudiness and precipitation gradually clears the warm sector over southeastern TX. Over 1000 J/kg MLCAPE may materialize if surface temperatures can exceed 70 F given expected mid to upper 60s F dewpoints beneath 7-8 C/km mid-level lapse rates. A surface cold front will sweep southeastward toward eastern TX. However, the mid-level trough should pivot northeastward through the day. As such, the surface low and accompanying low-level jet are poised to depart the southern Plains and track away from the axis of greater moisture and instability, which should limit severe potential to some degree. Still, low-level convergence along the cold front should support thunderstorm development by afternoon peak heating across the TX coastal plain to the Sabine River Valley. Strong enough flow along the western periphery of the departing low-level jet, beneath modest westerlies, will support elongated hodographs and over 30 kts of effective bulk shear. Given the aforementioned buoyancy, multicells and perhaps a couple of supercells are possible. Isolated severe gusts/hail are possible, and a tornado cannot be ruled out. ..Squitieri.. 11/27/2025 $$