Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
407 ACUS48 KWNS 180856 SWOD48 SPC AC 180854 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Wed Sep 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Lower-end severe potential should return on D4/Saturday in advance of a southern-stream shortwave trough over the Southwest. A mid-level jetlet, with 500-mb winds from 50-60 kts, is progged to eject across NM as the shortwave trough reaches the Four Corners area. A mesoscale corridor of severe storms might develop Saturday afternoon across a part of eastern NM or Far West TX. The expected buoyancy plume should be modest in amplitude and rather confined spatially owing to mid-level temperatures warmer than -3 C at 500 mb across much of TX. This shortwave trough may weaken slightly as it progresses towards the central Great Plains on D5/Sunday. But moderate mid-level southwesterlies may overspread a plume of rich low-level moisture arcing to the west-northwest from the Mid/Lower MS Valley. A mesoscale corridor of focused severe potential could develop in parts of KS/NE to western MO. Predictability for each scenario on D4-5 remains too low to confidently delineate a 15 percent area at these spatiotemporal scales. Larger-scale pattern predictability becomes too low into early next week. ..Grams.. 09/18/2024