Categorical Graphic
Probabilistic Graphic
Probability of severe weather within 25 miles of a point. Hatched Area: 10% or greater probability of significant severe within 25 miles of a point.

   SPC AC 270553
   
   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1253 AM CDT WED APR 27 2011
   
   VALID 281200Z - 291200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN U.S. FROM THE
   HUDSON VALLEY REGION SSWWD INTO N FL...
   
   ...SYNOPSIS...
   WHILE THE LARGE ERN U.S. UPPER TROUGH CONTINUES PROGRESSING EWD WITH
   TIME...A SECOND TROUGH IS FORECAST TO DIG SEWD ACROSS THE PAC NW/NRN
   INTERMOUNTAIN REGION THIS PERIOD.  A SURFACE COLD FRONT ACCOMPANYING
   THE ERN UPPER SYSTEM SHOULD SHIFT FROM E OF THE APPALACHIANS TO OFF
   THE ATLANTIC COAST BY THE END OF THE PERIOD...WHILE A FRONT
   ASSOCIATED WITH THE WRN SYSTEM ADVANCES SEWD ACROSS THE NWRN U.S.
   AND EXTENDS FROM THE NRN PLAINS SWWD INTO THE GREAT BASIN REGION
   LATE.  THE ERN U.S. FRONT -- ADVANCING ACROSS THE ATLANTIC COAST
   STATES -- WILL BE THE PRIMARY FOCUS FOR SEVERE STORMS THIS PERIOD.
   
   ...ERN U.S. FROM THE HUDSON VALLEY SSWWD TO N FL...
   LINE OF CONVECTION -- AND EMBEDDED SEVERE THREAT -- IS EXPECTED TO
   BE ONGOING AT THE START OF THE PERIOD NEAR/AHEAD OF THE COLD
   FRONT...WHICH SHOULD BE LYING E OF THE CENTRAL AND SRN APPALACHIANS
   BY THE START OF THE PERIOD.  STEADY EWD PROGRESS OF THE FRONT WILL
   LIKEWISE DRIVE A STEADILY ADVANCING LINE OF STORMS THROUGH THE
   AFTERNOON.  WITH LIMITED AFTERNOON HEATING AND A MOIST PRE-FRONTAL
   BOUNDARY LAYER...MODEST DESTABILIZATION /500 TO 1000 J/KG
   MIXED-LAYER CAPE/ WILL SUPPORT A DIURNAL INCREASE IN STORM
   COVERAGE/INTENSITY WITHIN THE CONVECTIVE LINE.  
   
   WHILE FLOW ALOFT WILL REMAIN QUITE STRONG AS THE POTENT UPPER SYSTEM
   ADVANCES...FAIRLY UNIDIRECTIONAL WIND FIELD WITH HEIGHT -- ROUGHLY
   PARALLEL TO THE FRONT/CONVECTIVE LINE -- IS NOT HIGHLY SUPPORTIVE OF
   WIDESPREAD WIND DAMAGE.  GREATEST POTENTIAL FOR WIND -- ALONG WITH
   ISOLATED TORNADOES AND MARGINAL HAIL -- APPEARS TO EXIST ACROSS THE
   ERN CAROLINAS -- WHERE INCREASED /30%/ SEVERE PROBABILITY WILL BE
   INTRODUCED.  
   
   THREAT SHOULD DIMINISH BY EVENING...WITH MOST CONVECTION MOVING
   OFFSHORE -- FOLLOWED SHORTLY BY THE COLD FRONT ITSELF.  THE ONLY
   LINGERING THREAT INTO THE OVERNIGHT HOURS MAY BE ACROSS SERN
   GA/FL...THOUGH WEAKER FLOW ALOFT ACROSS THIS REGION LATE IN THE
   PERIOD SUGGESTS THAT THREAT SHOULD REMAIN SOMEWHAT ISOLATED/LIMITED.
   
   ..GOSS.. 04/27/2011
   
   CLICK TO GET WUUS02 PTSDY2 PRODUCT

   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z