Categorical Graphic
Probabilistic Tornado Graphic
Probabilistic Damaging Wind Graphic
Probabilistic Large Hail Graphic

   SPC AC 240544
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1244 AM CDT SAT MAR 24 2007
   
   VALID 241200Z - 251200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CNTRL
   PLAINS...
   
   ...PLAINS...
   UPPER LOW OVER SRN NM IS FORECAST TO OPEN INTO A WAVE AND TRANSLATE
   ACROSS THE CNTRL PLAINS SATURDAY AND SATURDAY NIGHT.  IMPULSE
   DIGGING SWD ALONG WEST SIDE OF THIS SYSTEM WILL HELP MAINTAIN A
   TROUGH SWD INTO NWRN MEXICO RESULTING IN THE DOWNSTREAM SUB-TROPICAL
   HIGH TO BUILD WWD INTO THE SRN HIGH PLAINS THROUGH THE DAY.  AT THE
   SURFACE...A LEE-LOW WILL INTENSIFY ACROSS ERN CO AND DEVELOP NEWD
   INTO SWRN NEB BY LATE SATURDAY AFTN...THEN INTO NCNTRL NEB BY 12Z
   SUNDAY.  A DRYLINE/FRONT TO THE S OF THE LOW WILL SWEEP EWD ACROSS
   NEB...CNTRL KS AND THE TX/OK PNHDLS BY LATE SATURDAY NIGHT.  A WARM
   FRONT WILL LIFT NWD THROUGH THE CORN BELT AND MIDWEST.  BOTH
   FRONTS/DRYLINE WILL BE THE FOCI FOR TSTMS...POSSIBLY SEVERE SATURDAY
   AFTN/NIGHT.
   
   A LOOPY SEMI-ORGANIZED LINEAR MCS WILL LIKELY BE ONGOING AT 12Z FROM
   THE TX S PLAINS NWD INTO NEB.  ISOLD HAIL OR HIGH WINDS MAY
   ACCOMPANY A FEW OF THESE STORMS VERY EARLY IN THE PERIOD FOLLOWED BY
   A WEAKENING TREND.  ALL MODELS AGREE THAT CLOUD DEBRIS/PCPN SHOULD
   MOVE NORTHEAST INTO THE MO RVR VLY AND CORN BELT BY LATE MORNING
   WITH A MID-LEVEL DRY SLOT PUNCHING NWD AHEAD OF THE EJECTING UPPER
   SYSTEM THROUGHOUT THE WRN HIGH PLAINS BY EARLY AFTN.
   
   SELY LOW-LEVEL FLOW SHOULD MAINTAIN 55-60 DEG F DEW POINTS
   THROUGHOUT THE SRN PLAINS WITH RECOVERY EXPECTED ALONG/AHEAD OF THE
   SHARPENING FRONT/DRYLINE ACROSS ERN CO...NWRN KS AND NEB BY
   MID-AFTN.  RESIDENT STEEP MID-LEVEL LAPSE RATES OF 7.5-8 C PER KM
   ATOP THIS MOISTURE AND THE EXPECTED INSOLATION WILL RESULT IN
   MLCAPES OF 1000-1500 J/KG.
   
   EXIT REGION OF A 95 KT H25 JET AND ASSOCD UVV WILL SPREAD ACROSS ERN
   CO BY 18Z AND INTO KS AND NEB BY 21Z.  THIS SHOULD ENHANCE THE
   FRONTAL/DRYLINE CIRCULATION AND RESULT IN CONVECTIVE INITIATION
   ACROSS NWRN KS AND SWRN NEB BETWEEN 21-00Z.  FARTHER W ALONG THE WWD
   EXTENSION OF THE FRONT/SFC LOW...STORMS WILL TEND TO BE HIGH- BASED
   WITHIN A WEAKLY SHEARED ENVIRONMENT. BUT SET-UP WILL BE SUPPORTIVE
   FOR ISOLD NON-SUPERCELLULAR TORNADOES.  FARTHER E... TSTMS WILL
   BEGIN TO ENCOUNTER MORE SUBSTANTIAL MOISTURE/ INSTABILITY AND NEARLY
   55 KTS OF VERTICAL SHEAR ACROSS NRN/CNTRL KS AND CNTRL/SRN NEB
   DURING THE EVENING.  THUS...SUPERCELLS WITH LARGE HAIL WILL BE
   LIKELY.  BOUNDARY ORIENTATION WITH RESPECT TO THE 2-8KM SHEAR WILL
   RESULT IN A MIX OF STORM MODES...WITH PERHAPS HIGHER PROBABILITIES
   FOR DISCRETE STORMS ALONG THE KS/NEB BORDER.  ANY RIGHT MOVING
   MEMBERS WILL ACQUIRE ENOUGH SRH FOR A TORNADO THREAT DURING THE
   EVENING...PARTICULARLY IN NCNTRL KS AND SCNTRL NEB.
   
   ISOLD TSTMS MAY FORM AS FAR S AS NWRN OK SATURDAY EVENING. 
   BUT...GIVEN THAT THE MAIN FORCING PASSES N OF THE REGION AND LARGE
   SCALE RIDGING/SUBSIDENCE BEGINS S OF THE KS BORDER...PROSPECTS FOR
   DEEP MOIST CONVECTION ALONG THE DRYLINE SEEM SLIM.
   
   AS THE SLY LOW-LEVEL FLOW ACCELERATES SATURDAY NIGHT...STORMS ACROSS
   THE CNTRL PLAINS WILL EVOLVE INTO AN MCS AND TRACK ENEWD INTO THE
   CORN BELT AND UPPER MS VLY.  THE SEVERE THREATS WILL GRADUALLY
   DIMINISH...BUT ISOLD STORMS MAY STILL PRODUCE DAMAGING WINDS/HAIL
   INTO THE NIGHT TOWARD IN THE MO RVR VLY ALONG SRN PERIPHERY OF THE
   STORM COMPLEX.
   
   FINALLY...TSTMS MAY FORM ALONG THE HIGHER TERRAIN OF MEXICO ADJACENT
   TO THE TX BORDER SATURDAY AFTN/EVE WHERE MOIST UPSLOPE AND FAVORABLE
   HEATING EXIST AHEAD OF AN APPROACHING HIGH-LEVEL SPEED MAX.  THIS
   ACTIVITY MAY SPREAD/DEVELOP NWD INTO FAR SW TX SATURDAY NIGHT...BUT
   OVERALL CONFIDENCE IS LOW.
   
   ..RACY/CROSBIE.. 03/24/2007
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z