Apr 27, 2012 1630 UTC Day 1 Convective Outlook
Updated: Fri Apr 27 16:16:22 UTC 2012
Probabilistic to Categorical Outlook Conversion Table
Public Severe Weather Outlook

The SPC is forecasting ...severe thunderstorms expected over parts of central and eastern kansas and far western missouri today....   Please read the latest public statement about this event.  View What is a Watch? clip.

Categorical Graphic
20120427 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20120427 1630 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Probabilistic Damaging Wind Graphic
20120427 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Probabilistic Large Hail Graphic
20120427 1630 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
   SPC AC 271613
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1113 AM CDT FRI APR 27 2012
   
   VALID 271630Z - 281200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS OVER CENTRAL/ERN KS INTO WRN
   MO...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL PLAINS INTO
   THE LOWER MO VALLEY...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN GA INTO SC...
   
   ...KS/WRN MO AREA...
   WATER VAPOR IMAGERY INDICATES AN INTENSE UPPER VORTICITY MAX OVER
   EXTREME NWRN KS.  THIS SYSTEM IS EXPECTED TO MOVE ENEWD AND THEN
   NEWD OVER THE MO RIVER VALLEY AND WEAKEN TONIGHT AS THE PRIMARY
   UPPER LOW OVER DEVELOPS OVER THE NRN ROCKIES...AND PROVIDE STRONG
   DYNAMIC FORCING FOR ASCENT.  AT THE SURFACE...A CO-LOCATED DEEP LOW
   OVER EXTREME NWRN KS IS FORECAST TO MOVE EWD INTO CENTRAL KS THIS
   AFTERNOON...CONTINUING TOWARD NWRN MO TONIGHT.  A WARM FRONT
   EXTENDING ESEWD FROM THE LOW WILL SLOWLY LIFT NWD AS EXTENSIVE
   CLOUDS OVER CENTRAL/ERN KS WILL BE SLOW TO DIMINISH.  A DRY LINE
   ARCING SWD FROM THE LOW ACROSS WRN OK WILL SURGE EWD ACROSS SRN KS
   AND OK THIS AFTERNOON IN RESPONSE TO INCREASING DEEP LAYER WESTERLY
   FLOW ON THE SRN PERIPHERY OF THE UPPER SYSTEM.
   
   A NARROW LINE OF CONVECTION IS CURRENTLY INDICATED BY VISIBLE
   SATELLITE AND RADAR FROM NEAR HLC SWD TO EAST OF DDC...WITH BREAKS
   IN CLOUD COVER NOTED IMMEDIATELY IN ADVANCE OF THE CONVECTIVE LINE. 
   STRONGER HEATING WILL ALSO OCCUR OVER MUCH OF OK WHERE FEWER CLOUDS
   ARE PRESENT...AND AS MOISTURE SPREADS NWD IN ASSOCIATION WITH THE
   WARM FRONT...SURFACE DEWPOINTS IN THE LOW/MID 60S WILL BECOME MORE
   COMMON OVER PARTS OF CENTRAL/ERN KS INTO WEST CENTRAL/SWRN MO BY
   LATER THIS AFTERNOON AND EVENING.  12Z REGIONAL RAOBS EXHIBIT STEEP
   MID LEVEL LAPSE RATES WHICH WILL ENHANCE INSTABILITY...WITH MLCAPE
   REACHING 1500-2000 J/KG.  HOWEVER...THE ASSOCIATED EML WILL LIKELY
   CAP DEVELOPMENT OF SURFACE BASED STORMS OVER MUCH OF OK...WITH
   PRIMARY TSTM ACTIVITY SPREADING ACROSS PARTS OF KS INTO MO. 
   FAVORABLE DEEP LAYER SHEAR /40-50 KT OVER THE LOWEST 6 KM/ WILL
   PROMOTE DEVELOPMENT OF SUPERCELLS...AND SUFFICIENT LOW LEVEL
   SHEAR/SRH COUPLED WITH LOW LCL HEIGHTS SUGGEST POTENTIAL FOR
   TORNADIC SUPERCELLS TO DEVELOP...ESPECIALLY ALONG/NEAR THE WARM
   FRONT WHERE A FEW STRONG TORNADOES WILL BE POSSIBLE.  VERY LARGE
   HAIL AND DAMAGING WIND GUSTS WILL ALSO BE POSSIBLE AS STORMS
   PROGRESS EWD INTO WRN MO BY EVENING.  THE ACTIVITY IS EXPECTED TO
   GRADUALLY WEAKEN AFTER 03Z AS DIURNAL BOUNDARY LAYER COOLING OCCURS.
   
   
   ...NERN GA INTO SC...
   RELATIVELY FEW CLOUDS WILL ALLOW STRONG HEATING TO OCCUR THIS
   AFTERNOON AS A COLD FRONT SETTLES SWD ACROSS THE AREA.  SURFACE DEW
   POINTS NEAR 60F WILL PERMIT DEVELOPMENT OF STEEP LOW LEVEL LAPSE
   RATES IN THE PRE-CONVECTIVE ENVIRONMENT.  MODEL GUIDANCE IS
   CONSISTENT INDICATING STORMS WILL DEVELOP IN A CORRIDOR FROM THE SRN
   APPALACHIANS ACROSS SC THIS AFTERNOON AS A WEAK PERTURBATION IN THE
   MID/UPPER LEVEL FLOW TRAVERSES THE REGION.  WINDS ALOFT/DEEP LAYER
   SHEAR WILL BE SUFFICIENTLY STRONG TO SUPPORT ORGANIZED MULTI-CELL
   CONVECTION...WITH STRONGER CELLS CAPABLE OF PRODUCING LARGE HAIL AND
   STRONG WIND GUSTS.  THE SEVERE THREAT IS EXPECTED TO DIMINISH AFTER
   SUNSET.
   
   ..WEISS/MOSIER.. 04/27/2012
   
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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z