CATEGORICAL OUTLOOK
TORNADO OUTLOOK
WIND OUTLOOK
HAIL OUTLOOK
SPC AC 041630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT MON JUN 04 2012 VALID 041630Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER OH VALLEY/MIDWEST ACROSS THE SOUTH/SOUTHEAST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SRN PLAINS AND ADJACENT HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE INTERIOR NORTHWEST ACROSS THE CONTINENTAL DIVIDE TO MT HIGH PLAINS... ...SOUTH AND SOUTHEAST... MCS ACROSS AL/GA HAS WEAKENED THROUGH THE MORNING AND RENEWED CONVECTIVE DEVELOPMENT HAS OCCURRED ON ITS FLANK...ACROSS WRN TN AND NRN MS. STORMS NOW ACROSS NRN MS MAY BE AIDED BY LIFT ASSOCIATED WITH A WELL-DEFINED MCV OVER AR AND ARE LIKELY ROOTED ABOVE A CAPPED BOUNDARY LAYER. A BELT OF 40-50KT MID LEVEL FLOW IS OBSERVED IN VWP DATA...COINCIDENT WITH AREAS OF CONVECTION AND/OR RADAR ECHOES ASSOCIATED WITH CONVECTIVE DEBRIS. THIS STRONGER FLOW EXISTS FROM AR EAST TO SC WHILE VISIBLE IMAGERY CONTINUES TO DEPICT NEARLY CLOUD-FREE CONDITIONS TO THE SOUTH OF THE CONVECTION AND STRONGER DEEP-LAYER SHEAR. THERE REMAINS SOME POTENTIAL FOR STRONGER SURFACE-BASED UPDRAFTS TO EVOLVE AS BOUNDARY LAYER WARMS THROUGH THE AFTERNOON FROM AL ACROSS SRN GA AND EXTREME SRN SC. LIFT ALONG THE CONVECTIVE COLD POOL AND DIFFERENTIAL HEATING ZONE...IN CONCERT WITH WEAK MCV ACROSS AL SHOULD...SHOULD SUPPORT AN INCREASE IN SEVERE HAIL/WIND POTENTIAL AS THE CONVECTION SPREADS ESEWD THIS AFTERNOON. GIVEN THE WEAKENING TRENDS THROUGH THE MORNING...IT IS UNCERTAIN WHETHER THIS SEVERE POTENTIAL WILL BECOME ALL THAT WIDESPREAD OR REMAIN ISOLATED IN CHARACTER. ANOTHER MCS MAY ALSO TAKE FORM OUT OF THE ELEVATED CONVECTION ACROSS NRN MS. IN ADDITION TO DIURNAL DESTABILIZATION...INCREASE IN THIS ACTIVITY MAY BE FURTHER SUPPORTED BY AFOREMENTIONED MCV ACROSS AR. UNCERTAINTY EXISTS REGARDING THE EVOLUTION IN THIS FLANKING MCS AS INHIBITION AND SHEAR ARE SOMEWHAT LESS SUPPORTIVE OF ORGANIZED STORMS WITH WWD EXTENT TOWARD THE LOWER MS VALLEY. ...MT EAST OF THE DIVIDE/HIGH PLAINS... A WARM FRONT EXTENDING W-E FROM THE NRN GREAT BASIN ACROSS NRN WY/SRN MT WILL ADVANCE NWD WHILE SFC LOW PRESSURE INTENSIFIES ACROSS WRN ID IN RESPONSE TO INCREASING LARGE-SCALE ASCENT IN ADVANCE OF AN APPROACHING/AMPLIFYING EAST-PACIFIC SHORTWAVE TROUGH. WAA NORTH OF THE FRONT CONTINUES TO SUPPORT ACCAS AND ISOLATED SHOWERS/STORMS WITHIN AN ARC FROM E-CNTRL ID ACROSS CNTRL/N-CNTRL MT AND INTO SERN MT. THE WAA AMPLIFY THE DOWNSTREAM RIDGE...WHOSE AXIS CURRENTLY LIES N-S OVER THE NRN HIGH PLAINS WITH THE RIDGE AXIS SHIFTING EWD THROUGH THE PERIOD. HEIGHT FALLS LEADING THE AFOREMENTIONED SHORTWAVE TROUGH ARE NOT FORECAST TO COMMENCE IN EARNEST UNTIL LATE TONIGHT...MAINLY AFFECTING SWRN MT. AS THE WARM FRONT EMERGES OVER THE HIGH PLAINS OF CNTRL/ERN MT...IT WILL BECOME BETTER DEFINED AS WEAK LEE CYCLOGENESIS OCCURS OVER CNTRL MT. RELATIVELY RICHER LOW-LEVEL MOISTURE IS ANTICIPATED NEAR AND NORTH OF THE WARM FRONT...WHERE SFC DEWPOINTS MAY HOLD IN THE 50S...ESPECIALLY ACROSS CNTRL/N-CNTRL MT. EVEN STRONGER VERTICAL MIXING SOUTH OF THE FRONT WITHIN THE DEEPER BOUNDARY LAYER MAY YIELD SOMEWHAT LOWER DEWPOINTS FARTHER SOUTH TOWARD SWRN MT. AND...WITH STRONG SFC HEATING...MLCAPE VALUES OF 750-1500 J/KG SHOULD DEVELOP ACROSS A LARGE PART OF MT...HIGHEST IN AREAS REMOVED FROM CLOUD COVER. SWRN MT MOUNTAINS ALSO SERVE AS ELEVATED HEAT SOURCES...AND PROVIDE A ZONE OF CONVECTIVE INITIATION BETWEEN 21Z AND 23Z. STORMS WILL TRACK QUICKLY NNEWD/NEWD ACROSS THE NRN ROCKY MOUNTAIN FRONT AND ADJACENT HIGH PLAINS OF CNTRL/N-CNTRL MT INTO THE EARLY EVENING. OTHER STORMS MAY DEVELOP ACROSS THE MOUNTAINS SW/W OF BILLINGS BY LATE AFTERNOON AND TRACK SIMILAR TO THOSE FARTHER WEST...THOUGH INITIATION IS NOT AS CERTAIN FARTHER EAST UNDER THE MID-LEVEL RIDGE AXIS. GIVEN STRONG MID-LEVEL FLOW SUPPORTING 45-55 KT OF DEEP SHEAR...JUXTAPOSED WITH THE AFOREMENTIONED BUOYANCY...PERSISTENT SUPERCELL STRUCTURES WILL BE POSSIBLE /POSSIBLY EVOLVING INTO BOWING LINE SEGMENTS/...ESPECIALLY WITH CONVECTION ACROSS CNTRL/N-CNTRL MT NEAR AND NORTH OF THE WARM FRONT. SVR WIND/HAIL WILL BE OF CONCERN WITH THESE STORMS...AND SOME SIGNIFICANTLY SVR WIND WILL BE POSSIBLE. A TORNADO THREAT MAY ALSO DEVELOP WITH THE STRONGEST/MOST PERSISTENT SUPERCELLS NEAR AND NORTH OF THE FRONT...EAST OF THE FRONT RANGE TOWARD GREAT FALLS AND HAVRE. BACKED SFC WINDS IN THESE AREAS WILL SUPPORT THE GREATEST LOW-LEVEL HODOGRAPH CURVATURE. WHILE ADDITIONAL STORMS COULD MOVE INTO THE AREA FROM THE WEST LATER TONIGHT AS STRONGER DEEP FORCING FOR ASCENT ARRIVES...CINH OWING TO THE INCREASINGLY STABLE NOCTURNAL BOUNDARY LAYER WILL LIKELY MITIGATE THE SVR THREAT...THOUGH SOME HAIL CANNOT BE RULED OUT WITH THE STRONGEST STORMS LATE TONIGHT IF THEY CROSS THE CONTINENTAL DIVIDE. ...INTERIOR NW/WEST OF THE DIVIDE... LARGE-SCALE FORCING FOR ASCENT WILL CONTINUE TO INCREASE IN ADVANCE OF APPROACHING EAST-PACIFIC SHORTWAVE TROUGH. STORMS SHOULD DEVELOP OVER THE HIGHER TERRAIN OF ERN ORE AND W-CNTRL ID BEFORE MOVING QUICKLY NNEWD ACROSS ERN WA AND NWRN ID NEAR AND AHEAD OF THE FRONT ATTENDANT TO THE SHORTWAVE TROUGH. SFC HEATING WILL ALLOW FOR POCKETS OF MARGINAL TO MODERATE DESTABILIZATION AS PACIFIC MOISTURE CROSSES THE REGION. STRONG MERIDIONAL FLOW WILL SUPPORT EFFECTIVE BULK SHEAR MAGNITUDES IN EXCESS OF 50 KT...WITH SUPERCELLS AND BOWING LINE SEGMENTS LIKELY EVOLVING THROUGH THE LATE AFTERNOON INTO THE EVENING. WHERE SFC WINDS REMAIN RELATIVELY MORE BACKED NEAR A NWD-ADVANCING WARM FRONT FROM ERN ID AND WRN MT AND ACROSS REGIONS OF TERRAIN-CHANNELED FLOW...A TORNADO CANNOT BE COMPLETELY RULED OUT. INCREASING CINH AFTER DARK SHOULD SERVE TO LIMIT OVERALL SVR POTENTIAL. ...SRN HIGH PLAINS/W TX TO RED RIVER... RESIDUAL DEEP-LAYER FRONTAL ZONE WAS FRAGMENTED BY NUMEROUS STORM CLUSTERS/OUTFLOWS FROM WRN AR/SRN OK WWD ACROSS NWRN TX AND INTO THE SRN HIGH PLAINS. THIS ENTIRE REGION LIES BENEATH WEAK AND VARIABLE MID LEVEL FLOW ON THE ORDER OF 10-20KT AND GENERALLY AMBIGUOUS INDICATIONS FOR LARGE SCALE ASCENT. STRONG HEATING AND ABUNDANT MOISTURE WILL AGAIN CONTRIBUTE TO THE DEVELOPMENT OF WEAKLY CAPPED MODERATE TO STRONG INSTABILITY ACROSS MUCH OF THE REGION THIS AFTERNOON. POST-FRONTAL UPSLOPE FLOW AND DIFFERENTIAL HEATING ACROSS THE HIGHER TERRAIN WILL RESULT IN STORM INITIATION ACROSS CO/NM DURING THE AFTERNOON. ADDITIONAL DEVELOPMENT APPEARS POSSIBLE ALONG THE DECAYING FRONTAL/OUTFLOW SEGMENT...SOUTH OF THE RED RIVER...BY LATE IN THE DAY OR EARLY EVENING. WHILE ALL OF THIS CONVECTION WILL OCCUR AMIDST GENERALLY WEAK FLOW...MAGNITUDE OF AVAILABLE INSTABILITY...A DEEPLY MIXED/HOT BOUNDARY LAYER...AND BOUNDARY/STORM INTERACTIONS...CAN COMPENSATE FOR LACK OF STRONGER SHEAR TO SUPPORT SCATTERED SEVERE STORMS WITH HAIL AND HIGH WINDS. ...ERN MO/SRN IL TO WRN TN... AN ASSORTMENT OF DETERMINISTIC/CONVECTION ALLOWING GUIDANCE ARE SUGGESTIVE OF SCATTERED POTENTIALLY STRONG/SEVERE TSTM DEVELOPMENT BY MID/LATE AFTERNOON WITHIN A NNW-SSE CORRIDOR ACROSS THE REGION. AMID AMPLIFYING NORTHWESTERLY FLOW ALOFT...THIS WOULD BE IN VICINITY OF A WEAK SURFACE LOW/ASSOCIATED FRONTAL BOUNDARY. AMPLE MOISTURE AND HEATING ON THE SOUTHWEST EDGE OF A MORNING CLOUD DECK ACROSS IL/INDIANA WILL ALLOW FOR MODERATE DESTABILIZATION WITH 2000-3500 J/KG MLCAPE ALONG/SOUTHWEST OF THE FRONT. AIDED BY MODERATELY STRONG NORTHWESTERLY FLOW ALOFT /MAXIMIZED ALONG AND NORTHEAST OF THE FRONT/...STORMS SHOULD TRACK SOUTHEASTWARD THROUGH LATE AFTERNOON AND EVENING ACROSS THE MIDDLE MS VALLEY INCLUDING THE MO BOOTHEEL VICINITY AND WESTERN PORTIONS OF KY/TN WHILE POSING A RISK FOR DAMAGING WINDS/SEVERE HAIL. ...SRN FL... VERY SMALL AREA OF S FL...IMMEDIATELY NEAR EAST COAST SEA BREEZE...MAY SEE DEVELOPMENT OF VIGOROUS DEEP CONVECTION THIS AFTERNOON. A WET MICROBURST OR SMALL HAIL EVENT CANNOT BE COMPLETELY RULED OUT. ..CARBIN/GUYER/COHEN.. 06/04/2012 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z CURRENT UTC TIME: 1638Z (11:38AM), RELOAD THIS PAGE TO UPDATE THE TIME 
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