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