Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
355 ACUS48 KWNS 061047 SWOD48 SPC AC 061046 Day 4-8 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0446 AM CST Fri Mar 06 2026 Valid 091200Z - 141200Z CORRECTED FOR TEXT ...DISCUSSION... ...Day 4/Monday... A weak upper shortwave impulse is expected to migrate across the Ozarks/Lower MS Valley on Monday. This will support a narrow corridor of enhanced westerly flow aloft atop a moistening boundary layer. Isolated thunderstorms may develop across the ArkLaTex to Lower MS Valley vicinity within the warm advection regime, and a few storms could become strong to locally severe. However, modest forcing and otherwise lack of low-level focus precludes a 15 percent delineation. ...Day 5/Tuesday into Day 6/Wednesday... An upper low and attendant shortwave trough over northwest Mexico is forecast to eject eastward toward the southern High Plains on Tuesday. At the same time, a broad upper trough within northern stream flow will develop east from the northern Plains to the Upper Midwest. As this occurs, a belt of enhanced southwesterly flow aloft will overspread a large warm/moist sector from the southern Plains to the Mid/Lower MS and Ohio Valleys. A complex surface pattern is expected to emerge, influenced by the split-flow upper troughing pattern. A baroclinic zone extending from OK to the Mid-MS Valley area will be one focus for severe thunderstorm potential. Meanwhile, lee surface troughing across west TX and a developing dryline will be another focus for severe storm development. While details remain uncertain, these surface features, combined with strengthening southwesterly flow overspreading a warm and unstable airmass, will likely foster a broad area of severe thunderstorm potential from the southern Plains into the Midwest. As the upper troughs from Day 5/Tuesday continue east across the southern Plains and Great Lakes on Day 6/Wednesday, a cold front is expected to develop southeast across the Ohio Valley into east Texas. Spread among forecast guidance increases during this time, leading to more uncertainty. However, most guidance has some overlap of favorable low-level moisture and instability with stronger mid/upper level flow across portions of east TX into the Lower MS Valley. As a result, a 15 percent area has been delineated. This area may need to shift/expand northeast with time depending on trends in model guidance, but currently, it is uncertain if sufficient destabilization will occur further northeast, precluding severe probabilities into the TN/OH Valleys vicinity. ...Days 7-8/Thursday-Friday... Predictability is low toward the end of the forecast period as forecast model spread continues to increase. While it is plausible some severe risk could persist into the Southeast on Day 7/Thursday as the upper trough over the Lower MS Valley continues to migrate east, uncertainty is too high to include probabilities at this time. ..Leitman.. 03/06/2026