SPC AC 190716

   Day 3 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0216 AM CDT Tue Sep 19 2023

   Valid 211200Z - 221200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
   CENTRAL AND SOUTHERN PLAINS...

   ...SUMMARY...
   At least isolated strong to severe thunderstorms are possible across
   portions of the Plains Thursday into Thursday night.

   ...Synopsis...
   A broad mid-level trough across the Interior West is expected to
   morph into an upper-level cutoff low while gradually progressing
   toward the Rocky Mountains on Thursday. A 500 mb speed max will
   translate toward the Four Corners region, encouraging a low-level
   mass response in the form of surface cyclogenesis across the central
   High Plains and incipient low-level jet development over the
   southern/central Plains by Thursday afternoon and evening. Low-level
   moisture advection beneath cooler temperatures aloft will generate
   sufficient instability, amid increasing deep-layer ascent, to
   support at least scattered thunderstorm development across the
   Plains. A few strong to severe storms are possible.

   ...Central and southern Plains...
   By Thursday afternoon, a surface low should form along the CO/KS
   border, with mid to upper 60s F surface dewpoints advecting
   northwestward across central portions of OK to NE. 7-8 C/km
   mid-level lapse rates overspreading this moisture will boost MLCAPE
   to 1500 J/kg, ahead of a diffuse dryline positioned over the High
   Plains. Though the dryline should remain quasi-stationary through
   the period, dynamic lift associated with the rapid approach of the
   aforementioned 500 mb speed max should foster scattered thunderstorm
   development by afternoon across parts of the central and southern
   Plains. 40+ kt 500 mb westerly winds, overspreading a 35-50 kt
   southwesterly low-level jet, will contribute to adequate wind shear
   for isolated multicell and supercell structures capable of mainly
   severe hail and wind gusts, though a tornado cannot be ruled out. By
   evening, one or two MCS structures may materialize owing to stronger
   convergence induced by the low-level jet. Should this occur,
   isolated severe gusts would become the dominant severe hazard.

   ..Squitieri.. 09/19/2023

   CLICK TO GET WUUS03 PTSDY3 PRODUCT

   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z