ZCZC SPCSWOMCD ALL ACUS11 KWNS 142315 SPC MCD 142315 OKZ000-150045- Mesoscale Discussion 1288 NWS Storm Prediction Center Norman OK 0615 PM CDT Tue Aug 14 2018 Areas affected...Portions of central Oklahoma Concerning...Severe potential...Watch unlikely Valid 142315Z - 150045Z Probability of Watch Issuance...20 percent SUMMARY...Potential exists for isolated large hail, strong wind gusts, and a brief tornado across central Oklahoma through approximately 03Z. Watch issuance appears unlikely at present, though. DISCUSSION...An expanding cluster of storms, aided by moist/confluent southerly boundary-layer flow, is maintaining some severe threat across central Oklahoma currently. KTLX and TOKC data indicate occasional supercellular structures embedded within this cluster. Although mid-level lapse rates are modest, rich low-level theta-e is yielding sufficient buoyancy in the hail-growth zone for a brief/isolated large hail threat. Additionally, backed surface winds amidst a very moist boundary-layer environment may support occasional low-level mesocyclones, which would enhance the threat for a few stronger gusts and perhaps a brief tornado this evening. Still, modest mid/upper flow and storm development largely parallel to deep-layer shear vectors should limit the threat enough to preclude watch issuance. ..Picca/Grams.. 08/14/2018 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TSA...OUN... LAT...LON 36109927 36339694 35999634 35019630 34739728 34339842 34699926 35759943 36109927 NNNN