CATEGORICAL OUTLOOK
TORNADO OUTLOOK
WIND. OUTLOOK
HAIL OUTLOOK
DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0736 AM CDT MON JUL 02 2012 VALID 021300Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT FROM ERN ND AND FAR NERN SD INTO THE UPPER GREAT LAKES... ...SYNOPSIS... PROMINENT UPPER RIDGE FROM THE S-CNTRL U.S. INTO CNTRL CANADA WILL BE TEMPORARILY DAMPENED BY A SHORTWAVE TROUGH MOVING THROUGH THE PRAIRIE PROVINCES AND NRN PLAINS/UPPER MS VALLEY. ELSEWHERE...A SLIGHT LOWERING OF MIDLEVEL HEIGHTS IS FORECAST ALONG THE ATLANTIC COAST IN CONJUNCTION WITH A SERIES OF WEAK PERTURBATIONS TRANSLATING SEWD INTO BASAL PORTION OF LARGE-SCALE TROUGH. AT THE SURFACE...MIGRATORY CYCLONE OVER SWRN ND WILL DEVELOP EWD INTO THE UPPER MS VALLEY WHILE A TRAILING COLD FRONT ADVANCES ACROSS THE DAKOTAS. AN ASSOCIATED WARM FRONT WILL LIFT NWD THROUGH THE UPPER GREAT LAKES IN ADVANCE OF SURFACE LOW WHILE ELSEWHERE LEE TROUGHS STRENGTHEN OVER THE CNTRL HIGH PLAINS AND THE PIEDMONT OF THE CAROLINAS AND GA. ...ERN ND/FAR NERN SD INTO UPPER GREAT LAKES... 12Z SURFACE AND UPPER-AIR OBSERVATIONS INDICATE A FAVORABLE OVERLAP OF RICH BOUNDARY LAYER MOISTURE AND STEEP MIDLEVEL LAPSE RATES INVOF WARM FRONT FOR THE DEVELOPMENT OF AN EXTREMELY UNSTABLE ENVIRONMENT BY AFTERNOON WITH MLCAPE VALUES APPROACHING 3000-4000+ J/KG. LATEST MODEL GUIDANCE IS IN REMARKABLY GOOD AGREEMENT IN SUGGESTING AN INCREASING LIKELIHOOD FOR SURFACE-BASED STORMS BY MID-LATE AFTERNOON OVER THE RED RIVER VALLEY AS CONVECTIVE INHIBITION IS SUFFICIENTLY DIMINISHED BY A COMBINATION OF LOW-LEVEL CONVERGENCE INVOF SURFACE TRIPLE POINT AND DCVA AHEAD OF SHORTWAVE TROUGH. MODEL-DERIVED HODOGRAPHS AHEAD OF SURFACE LOW EXHIBIT VERTICALLY VEERING WIND PROFILES WITH 30-40 KT OF EFFECTIVE BULK SHEAR. GIVEN THE DEGREE OF INSTABILITY FORECAST...INITIAL STORMS MAY EVOLVE INTO SUPERCELLS WITH AN ASSOCIATED RISK FOR VERY LARGE HAIL AND PERHAPS A TORNADO OR TWO. THEREAFTER...CONSENSUS OF CONVECTION-ALLOWING MODEL GUIDANCE INDICATES A HIGH PROBABILITY OF BOW ECHO FORMATION WITH THE POTENTIAL FOR A WIDESPREAD DAMAGING WIND EVENT SPREADING EWD/SEWD ACROSS NRN MN INTO NRN WI AND THE WRN U.P. OF MI TONIGHT INTO TUE MORNING. IT IS POSSIBLE THAT A PORTION OF THE SLIGHT RISK AREA COULD BE UPGRADED TO A MODERATE RISK IN LATER D1 UPDATES. ...CNTRL/ERN SD INTO THE CNTRL HIGH PLAINS... ISOLATED-WIDELY SCATTERED TSTMS WILL BE POSSIBLE THIS AFTERNOON INTO EVENING ALONG PRE-FRONTAL/LEE TROUGH OWING TO STRONG BOUNDARY LAYER HEATING. WHILE VERTICAL SHEAR WILL REMAIN RATHER WEAK...THE PRESENCE OF STEEP LAPSE RATES AND A HOT...DEEPLY-MIXED BOUNDARY LAYER WILL BE SUPPORTIVE OF GUSTY WINDS AND SOME HAIL IN THE STRONGEST STORMS. ...CAROLINAS... 12Z SOUNDINGS REVEAL THAT THE EXTENSIVE TSTM DEVELOPMENT SUNDAY AFTERNOON/NIGHT HAS RESULTED IN CONSIDERABLE AIR MASS OVERTURNING. MOREOVER...RESIDUAL CONVECTIVE DEBRIS/CLOUDINESS WILL SLOW DAYTIME HEATING WITH ONLY MODEST INSTABILITY ANTICIPATED TO DEVELOP BY AFTERNOON. THIS IN CONJUNCTION WITH MARGINAL VERTICAL SHEAR SUGGEST A DECREASED POTENTIAL FOR ORGANIZED SEVERE STORMS. THEREFORE...THE CATEGORICAL SLIGHT RISK HAS BEEN REMOVED FROM THE AREA. ...GA/NRN FL/AL... SURFACE ANALYSIS AND 12Z SOUNDINGS SUGGEST THAT COMPOSITE OUTFLOW BOUNDARY ASSOCIATED WITH SUNDAY/S TSTMS HAS PUSHED INTO CNTRL AL AND NRN FL WITH THE BHM THERMAL PROFILE INDICATING THE POTENTIAL FOR STRONGEST DESTABILIZATION DUE TO THE PRESERVATION OF AN EML/STEEP MIDLEVEL LAPSE RATES. THIS WOULD SUGGEST THE GREATEST RISK FOR ISOLATED SEVERE STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS ACROSS AL...THOUGH ISOLATED DAMAGING WIND GUSTS WILL ALSO BE POSSIBLE ACROSS PORTIONS OF GA AND NRN FL INTO THIS EVENING. ..MEAD/HURLBUT.. 07/02/2012 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z CURRENT UTC TIME: 1319Z (8:19AM), RELOAD THIS PAGE TO UPDATE THE TIME 
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