SPC 0600Z Day 2 Outlook
DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT WED MAY 02 2012 VALID 031200Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM A PORTION OF OK...CNTRL PLAINS INTO THE MID MS VALLEY...OH VALLEY AND GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF WRN TX... ...SYNOPSIS... BROAD LOW AMPLITUDE CYCLONIC FLOW WILL PERSIST OVER THE NRN THIRD OF THE COUNTRY. UPPER TROUGH IS FORECAST TO BEGIN TO AMPLIFY OVER THE PACIFIC NW RESULTING IN SLIGHT DOWNSTREAM HEIGHT RISES WITHIN THE SWLY FLOW REGIME ACROSS THE UPPER MS VALLEY AND GREAT LAKES. IMPULSE CURRENTLY MOVING INTO THE PACIFIC NW WILL MOVE THROUGH THE UPPER MS VALLEY...SRN ONTARIO AND NRN GREAT LAKES THURSDAY AFTERNOON. WEAK SRN STREAM IMPULSE MAY MOVE INTO THE SRN HIGH PLAINS. A QUASI-STATIONARY BAROCLINIC ZONE SHOULD STRETCH FROM KS THROUGH THE UPPER MS VALLEY INTO WRN PARTS OF THE GREAT LAKES. A SFC WAVE WILL DEVELOP ALONG THE UPPER MS VALLEY PORTION OF THIS BOUNDARY AND SHIFT NEWD RESULTING IN THE SWD ADVANCE OF THE FRONT DURING THE AFTERNOON AND EVENING. DRYLINE WILL PERSIST OVER THE SRN PLAINS. ...ERN PORTIONS OF CNTRL PLAINS INTO MID-UPPER MS VALLEY AND GREAT LAKES... A QUASI-STATIONARY FRONT WILL PERSIST WITHIN BROAD FETCH OF MODERATE SWLY FLOW ALOFT. THUNDERSTORMS WILL LIKELY BE ONGOING WITHIN ZONE OF ISENTROPIC ASCENT. SOME OF THIS ACTIVITY MAY PERSIST DURING THE DAY SUPPORTED BY SWLY LLJ THAT WILL SHIFT NEWD IN ASSOCIATION WITH EJECTING SHORTWAVE TROUGH. WARM SECTOR SOUTH OF THE ONGOING ACTIVITY WILL BECOME MODERATELY TO STRONGLY UNSTABLE WITH THE STRONGEST INSTABILITY EXPECTED WITH SWWD EXTEND INTO THE CNTRL PLAINS. ADDITIONAL STORMS MAY DEVELOP ALONG THE CONVECTIVELY REINFORCED BOUNDARY BY LATE AFTERNOON FROM NERN KS/SERN NEB INTO THE UPPER MS VALLEY...WITH MORE ISOLATED COVERAGE EXPECTED WITH SWWD EXTENT INTO THE CNTRL PLAINS DUE TO PRESENCE OF STRONGER CAP. DEEP LAYER WINDS MAY BE STRONGER FROM THE UPPER MID WEST INTO THE GREAT LAKES REGION IN ASSOCIATION WITH EJECTING IMPULSE. ACTIVITY MAY EVOLVE INTO ONE OR MORE MCS CLUSTERS AS THEY DEVELOP EWD DURING THE AFTERNOON AND EVENING. DAMAGING WIND AND LARGE HAIL ARE EXPECTED TO BE THE MAIN THREATS. ...SRN KS AND OK... THE ATMOSPHERE IS EXPECTED TO BECOME VERY UNSTABLE DURING THE AFTERNOON WHERE EML PLUME WILL PERSIST ABOVE MOIST AXIS. HOWEVER...THERE WILL LIKELY BE A SUBSTANTIAL CAP OVER MOST OF THIS AREA. AN ISOLATED STORM OR TWO WILL BE POSSIBLE FROM NEAR THE TRIPLE POINT IN SRN KS SWD ALONG THE DRYLINE OVER A PORTION OF WRN/CNTRL OK. MODELS INDICATE AT LEAST A WEAK SRN STREAM IMPULSE MAY MOVE INTO THIS REGION DURING PEAK HEATING ALONG WITH A BELT OF STRONGER FLOW ALOFT RESULTING IN SUFFICIENT SHEAR FOR SUPERCELLS. ...WRN TX... A SRN STREAM IMPULSE IS FORECAST TO MOVE INTO THE SRN PLAINS. A FEW STORMS MAY DEVELOP ALONG THE DRYLINE DURING THE AFTERNOON WITHIN A MODESTLY SHEARED ENVIRONMENT...BUT A BELT OF STRONGER FLOW ACCOMPANYING THE IMPULSE MAY RESULT IN SUFFICIENT SHEAR FOR AT LEAST MARGINAL SUPERCELL STRUCTURES WITH ISOLATED DAMAGING WIND AND HAIL THE MAIN THREATS. ..DIAL.. 05/02/2012
via SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day2otlk_0600.html
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