SPC 0730Z Day 3 Outlook
DAY 3 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0230 AM CDT FRI MAY 25 2012 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-MO VALLEY...CNTRL PLAINS AND UPPER MS VALLEY... ...MID-MO VALLEY/CNTRL PLAINS/UPPER MS VALLEY... AN UPPER-LEVEL LOW OVER THE NRN ROCKIES AND AN ASSOCIATED UPPER-LEVEL TROUGH EXTENDING SWD ACROSS THE INTERMOUNTAIN WEST IS FORECAST TO MOVE NEWD INTO THE CNTRL AND NRN HIGH PLAINS ON SUNDAY. AT THE SAME TIME...A WELL-DEFINED MID-LEVEL JET IS FORECAST TO EJECT NNEWD INTO THE NRN PLAINS. THE MOISTURE AND INSTABILITY AXIS SHOULD BE IN PLACE TO THE SOUTHEAST OF THE MID-LEVEL JET CORE FROM THE CNTRL PLAINS NNEWD INTO THE UPPER MS VALLEY WHERE THE MODELS SHOW MODERATE TO STRONG INSTABILITY. ALTHOUGH A CAPPING INVERSION IS EVIDENT ON FORECAST SOUNDINGS ACROSS MUCH OF THE WARM SECTOR SUNDAY AROUND MIDDAY...THE MODELS WEAKEN THE CAP DURING THE LATE AFTERNOON ALLOWING FOR THE DEVELOPMENT OF NUMEROUS THUNDERSTORMS. FORECAST SOUNDINGS EARLY SUNDAY EVENING SHOW THE BEST COMBINATION OF INSTABILITY AND DEEP LAYER SHEAR FROM NRN KS NEWD ACROSS ERN NEB WHERE SUPERCELL DEVELOPMENT APPEARS PROBABLE. MLCAPE VALUES OF 1500 TO 2500 J/KG WITH 0-6 KM SHEAR OF 50 KT AND STEEP MID-LEVEL LAPSE RATES SHOULD BE FAVORABLE FOR LARGE HAIL. ISOLATED VERY LARGE HAIL MAY ALSO OCCUR WITH THE MORE DOMINANT SUPERCELLS. WILL INTRODUCE A HATCHED AREA FOR HAIL OF GREATER THAN 2 INCHES IN DIAMETER JUST TO THE WEST OF THE OMAHA AREA. A TORNADO THREAT WILL ALSO BE POSSIBLE DUE TO STRONG LOW-LEVEL SHEAR ASSOCIATED WITH A BROAD LOW-LEVEL JET. AS STORMS RAPIDLY INCREASE IN COVERAGE...A TRANSITION FROM DISCRETE MODE TO A LINEAR-STRUCTURED MCS APPEARS POSSIBLE AS A COLD FRONT MOVES SEWD ACROSS THE REGION. THIS COULD RESULT IN AN INCREASING THREAT FOR WIND DAMAGE WITH TIME SUNDAY EVENING. ...GREAT LAKES REGION... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE GREAT LAKES REGION. BENEATH THE RIDGE...AN AXIS OF INSTABILITY IS FORECAST TO BE IN PLACE FROM WI EWD ACROSS LOWER MI. IN SPITE OF THE SUBSIDENCE ASSOCIATED WITH THE RIDGE...ISOLATED THUNDERSTORMS MAY DEVELOP ACROSS THE REGION AS SFC TEMPS WARM DURING THE DAY. FORECAST SOUNDINGS ACROSS WI AND LOWER MI SUNDAY AFTERNOON SHOW MODERATE INSTABILITY AND STEEP LAPSE RATES SUGGESTING A MARGINAL SEVERE THREAT COULD EXIST. ...SRN PLAINS... SOUTHWEST FLOW IS FORECAST ON SUNDAY ACROSS THE SRN PLAINS WHERE A DRYLINE SHOULD BE IN PLACE FROM SW KS SWD ACROSS WEST TX. FOR SUNDAY AFTERNOON...THE MODELS SHOW MODERATE INSTABILITY AND STEEP LAPSE RATES LOCATED ALONG AND TO THE EAST OF THE DRYLINE WHERE ISOLATED CONVECTION COULD INITIATE. ALTHOUGH THE THERMODYNAMICS SHOULD SUPPORT AN ISOLATED SEVERE THREAT...THE THREAT SHOULD REMAIN VERY ISOLATED MAINLY DUE TO WEAK LARGE-SCALE ASCENT. ..BROYLES.. 05/25/2012
via SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day3otlk_0730.html
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