| Categorical Graphic |
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| Probabilistic Tornado Graphic |
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| 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 |
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| 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 |
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| 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 110546 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1246 AM CDT SAT JUN 11 2011 VALID 111200Z - 121200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE UPPER OH VALLEY AND CNTRL APPALACHIANS... ...PLAINS... UPPER RIDGE IS EXPECTED TO BE SHUNTED EAST ACROSS THE PLAINS BY MID AFTERNOON AS LARGE SCALE TROUGHING BECOMES ESTABLISHED OVER THE NRN ROCKIES INTO THE GREAT BASIN. WITH A SLOWLY RETREATING SFC ANTICYCLONE OVER THE MS VALLEY REGION SELY BOUNDARY LAYER FLOW WILL UNDOUBTEDLY INCREASE ACROSS THE HIGH PLAINS FROM MT...SWD INTO THE TX PANHANDLE. THIS INTENSIFYING SELY FLOW WILL ALLOW A MORE MOIST AIR MASS TO RETURN NWWD INTO A REGION THAT WILL BE SUBSTANTIALLY SHEARED THROUGH A DEEP LAYER...ROUGHLY 30-40KT ACROSS MUCH OF THE PLAINS. LATEST MODEL GUIDANCE SUGGEST INTENSE SFC HEATING FROM NWRN TX INTO THE NEB PANHANDLE WILL OCCUR ALONG WRN FRINGES OF MOISTURE RECOVERY WHICH SHOULD EASILY YIELD SBCAPE VALUES APPROACHING 2000 J/KG. IN THE ABSENCE OF MEANINGFUL INHIBITION BY LATE AFTERNOON IT APPEARS LOW LEVEL UPSLOPE COMPONENT WILL PROVE MORE THAN ADEQUATE FOR THUNDERSTORM DEVELOPMENT. IN ADDITION...EARLY MORNING WV IMAGERY SUGGESTS A FAIRLY WELL DEFINED MID LEVEL SHORTWAVE TROUGH AND ASSOCIATED VORT MAX ARE EJECTING NEWD ACROSS NRN AZ TOWARD CO. THIS FEATURE SHOULD TIME FAVORABLY FOR AFTERNOON CONVECTION ACROSS THE CNTRL HIGH PLAINS. THIS APPEARS TO BE THE REGION OF HIGHEST CONFIDENCE FOR ROBUST SUPERCELL DEVELOPMENT AS MOISTURE RECOVERY SHOULD EASILY BE ATTAINED IN ADVANCE OF THIS SHORTWAVE TROUGH. FORECAST SOUNDINGS SUPPORT SUPERCELL DEVELOPMENT...AND VERY LARGE HAIL IN ADDITION TO ISOLATED TORNADOES SEEM REASONABLE. WITH AN INCREASING LLJ INTO WRN KS AFTER DARK A LARGE MCS COULD EVOLVE ACROSS THE CNTRL PLAINS. FARTHER NORTH...IT/S NOT ENTIRELY CLEAR WHICH IMPULSE WILL AFFECT THE HIGH PLAINS OF SERN MT INTO THE BLACK HILLS REGION BUT SHEAR PROFILES ARE EXPECTED TO IMPROVE SUCH THAT ANY STORMS THAT EVOLVE ACROSS THIS REGION WILL TEND TO ROTATE AND SUPERCELL STRUCTURES CAN BE EXPECTED. AS WITH THE CNTRL PLAINS ACTIVITY HAIL AND EVEN AN ISOLATED TORNADO CAN BE EXPECTED WITH THIS CONVECTION. ...UPPER OH VALLEY/CNTRL APPALACHIANS... UPPER MS VALLEY SHORTWAVE TROUGH WILL EJECT EWD ACROSS THE GREAT LAKES REGION AS MID LEVEL SPEED MAX INCREASES ACROSS WI/LOWER MI TOWARD SRN ONTARIO. THIS FEATURE WILL ENHANCE DEEP LAYER SHEAR PROFILES ACROSS THE NRN UPPER OH VALLEY REGION ALONG NRN FRINGES OF MORE BUOYANT AIR MASS. FORECAST SOUNDINGS AHEAD OF THE SFC FRONT SUGGEST CONVECTIVE TEMPERATURES WILL ONLY BE IN THE LOWER 80S ACROSS OH...WITH READINGS EVEN LOWER EXPECTED TO AID IN CONVECTIVE DEVELOPMENT OVER UPSTATE NY. FOR THIS REASON TSTMS SHOULD DEVELOP FAIRLY EARLY AND PROPAGATE SEWD INTO A MORE UNSTABLE AIR MASS DELINEATED BY FORECAST SLGT RISK. SHEAR PROFILES FAVOR PRIMARILY MULTI-CELL UPDRAFTS THOUGH A FEW WEAK SUPERCELLS MAY OCCUR ACROSS THE NRN HALF OF THE SEVERE RISK. DAMAGING WINDS AND HAIL ARE THE PRIMARY SEVERE THREATS. ..DARROW/ROGERS.. 06/11/2011 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z