THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN PLAINS ON SATURDAY

CATEGORICAL OUTLOOK 

 PROBABILISTIC OUTLOOK 

   SPC AC 070725          DAY 3 CONVECTIVE OUTLOOK       NWS STORM PREDICTION CENTER NORMAN OK     0225 AM CDT THU JUN 07 2012          VALID 091200Z - 101200Z          ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN     PLAINS...          ...SYNOPSIS...     THE WRN UPPER LOW/TROUGH IS FORECAST TO CONTINUE MAKING SLOW/STEADY     EWD PROGRESS...AND IS EXPECTED TO RESIDE OVER THE INTERMOUNTAIN     REGION BY THE END OF THE PERIOD.  ELSEWHERE...DOWNSTREAM RIDGING IS     FORECAST TO PREVAIL...AS THE ERN U.S. TROUGH CONTINUES ITS DEPARTURE     INTO THE NRN/WRN ATLANTIC.          AT THE SURFACE...A COLD FRONT IS FORECAST TO MOVE INTO/ACROSS THE     NRN PLAINS...THOUGH MODEL DIFFERENCES IN SPEED/TIMING OF THE FRONT     ARE EVIDENT.  STILL -- THE FRONT SHOULD ROUGHLY BISECT THE NRN     PLAINS THE 10/12Z.          ...N CENTRAL CONUS...     AS MENTIONED ABOVE...MODEL DEPICTION OF THE SPEED/TIMING OF THE     SURFACE FRONT VARIES -- WHICH COMPLICATES THE SEVERE WEATHER     FORECAST.  THE GFS AND ECMWF DEPICT A MORE NEUTRALLY-TILTED UPPER     TROUGH...AND THUS A SLOWER FRONTAL PROGRESSION AND MORE N-S     ORIENTATION OF THE FRONT AS IT CROSSES THE NRN PLAINS AND REACHES     THE CENTRAL DAKOTAS LATE.  MEANWHILE...THE NAM DEPICTS A MUCH MORE     POSITIVELY TILTED UPPER SYSTEM...AND THUS A FASTER FRONT THAT IS     ALIGNED MORE NE-SW.  BY THE END OF THE PERIOD...THE NAM EXTENDS THIS     FRONT FROM THE ARROWHEAD REGION OF MN SWWD INTO CENTRAL NEB.          OVERALL HOWEVER...IT APPEARS THAT FRONTAL PROGRESSION INTO A     STRONGLY DESTABILIZING BUT CAPPED AFTERNOON AIRMASS OVER THE DAKOTAS     CAN BE EXPECTED...WITH EVENTUAL STORM DEVELOPMENT TO OCCUR BY LATE     AFTERNOON.  THE GFS SOLUTION FAVORS THE WRN OR CENTRAL SD FOR     INITIATION...WITH THE NAM FAVORING NERN ND AND THEN INTO NWRN MN.      THOUGH THE INITIATION ZONE DIFFERS...THE VERY UNSTABLE AIRMASS     PROGGED TO BE IN PLACE /3000 TO 4000 J/KG MIXED-LAYER CAPE EXPECTED/     COMBINED WITH INCREASING MID-LEVEL SWLYS SPREADING EWD WITH TIME     ATOP LOW LEVEL SLY/SWLY FLOW SHOULD RESULT IN RAPID SUPERCELL     EVOLUTION ONCE THE CAP IS BREACHED.  VERY LARGE HAIL IS     EXPECTED...ALONG WITH LOCALLY DAMAGING WINDS AND POSSIBLY A COUPLE     OF TORNADOES.          GIVEN THE DEGREE OF INSTABILITY AND A LOW-LEVEL JET PROGGED TO     STRENGTHEN FROM THE SOUTH OVERNIGHT...SEVERE THREAT SHOULD CONTINUE     WELL INTO THE EVENING...SPREADING EWD WITH TIME AND LIKELY EVOLVING     INTO MORE OF A HAIL/ISOLATED WIND EVENT INTO THE OVERNIGHT HOURS.          ..GOSS.. 06/07/2012          NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z     CURRENT UTC TIME: 1330Z (8:30AM), RELOAD THIS PAGE TO UPDATE THE TIME