ZCZC SPCSWOMCD ALL ACUS11 KWNS 060420 SPC MCD 060420 OKZ000-KSZ000-NEZ000-060615- MESOSCALE DISCUSSION 1158 NWS STORM PREDICTION CENTER NORMAN OK 1120 PM CDT TUE JUL 05 2016 AREAS AFFECTED...A LARGE PART OF KS...FAR SRN NEB...NRN OK CONCERNING...SEVERE THUNDERSTORM WATCH 328...330... VALID 060420Z - 060615Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 328...330...CONTINUES. SUMMARY...THE SVR-TSTM RISK IS SPREADING SWD/SEWD ACROSS PORTIONS OF WRN/CNTRL KS...AND THE SVR RISK SHOULD SPREAD FARTHER S -- PERHAPS AS FAR SOUTH AS NRN OK -- DURING THE OVERNIGHT HOURS. DISCUSSION...CONGEALING CONVECTIVE CLUSTERS OVER PARTS OF WRN KS HAVE EVOLVED INTO A MORE ORGANIZED SYSTEM SURGING SWD IN PARTS OF NESS AND LANE COUNTIES KS. THIS IS CONSISTENT WITH THE NOCTURNAL INCREASE IN LOW-LEVEL SLYS DRIVING CONVECTIVE PROPAGATION SWD INTO THE STRENGTHENING LLJ. THE DDC VWP INDICATES 0.5-KM-AGL SLY FLOW HAVING INCREASED FROM 20 TO 30 KT DURING THE PAST FEW HOURS...RESULTING IN STRENGTHENING INFLOW FOR THE ONGOING CONVECTION. FURTHER STRENGTHENING OF THE NOCTURNAL BOUNDARY-LAYER WIND-SPEED MAXIMUM SHOULD FOSTER STRENGTHENING INFLOW ON THE SRN FLANK OF THE ONGOING CONVECTION DURING THE OVERNIGHT HOURS...WHILE WLY/NWLY MID-LEVEL FLOW YIELDS EWD/SEWD CELL ADVECTION. AS A RESULT...LOCALLY UPSCALE-GROWING CONVECTIVE CLUSTERS WILL CONTINUE SPREADING SWD/SEWD DURING THE NEXT SEVERAL HOURS. THE EARLIER 00Z DDC RAOB SUGGESTS THAT AMPLE BUOYANCY WILL EMANATE FROM BASE OF THE RESIDUAL MIXED LAYER...WITH MUCAPE ON THE ORDER OF 3000-4000 J/KG FOSTERING INTENSE UPDRAFTS AMIDST 35-50 KT OF EFFECTIVE BULK SHEAR. THIS WILL ALLOW SOME SVR RISK TO EXTEND S OF WW 330 INTO THE OVERNIGHT HOURS...AND LOCAL EXTENSION OF THE WW MAY BE NEEDED. FURTHERMORE...SOME ISOLATED SVR RISK CANNOT BE RULED OUT AS FAR S AS NRN OK LATER TONIGHT AS THE LLJ ENHANCES INFLOW. HOWEVER...GROWING NOCTURNAL MLCINH MAY BE DETRIMENTAL TO DOWNDRAFTS PENETRATING THE SFC-BASED NOCTURNAL STABLE LAYER. AS SUCH...THE ISSUANCE OF AN ENTIRELY NEW WW IS UNLIKELY. OTHER ISOLATED INTENSE CONVECTION CONTINUES DEVELOPING ACROSS PARTS OF N-CNTRL KS AT THE TERMINUS OF THE STRENGTHENING LLJ. IT IS POSSIBLE THAT THIS ACTIVITY MAY SUPPORT AN ISOLATED SVR RISK AS IT SPREADS ACROSS PARTS OF CNTRL/NRN KS. FARTHER N INTO FAR SRN NEB...THE SVR RISK ACROSS REMAINING-VALID PORTIONS OF WW 328 HAS LARGELY DIMINISHED OWING TO STABILIZATION ASSOCIATED WITH NOCTURNAL COOLING OF THE SFC LAYER...AS WELL AS PRIOR CONVECTIVE PROCESSING. ..COHEN/GUYER.. 07/06/2016 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...TOP...ICT...OUN...GID...DDC...GLD... LAT...LON 36719932 37480025 38340067 39100062 39779974 40229815 39259719 37079658 36639747 36719932 NNNN