CATEGORICAL OUTLOOK
TORNADO OUTLOOK
WIND OUTLOOK
HAIL OUTLOOK
DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT THU JUN 28 2012 VALID 281300Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ... ...SYNOPSIS... EXPANSIVE ANTICYCLONE NOW EXTENDING FROM THE SRN RCKYS TO THE LWR OH VLY WILL FURTHER ELONGATE W-E THIS PERIOD AS CNTRL PORTION TEMPORARILY IS SUPPRESSED BY PROGRESSIVE SHORTWAVE TROUGH CROSSING MB. THE MB SYSTEM SHOULD REACH JAMES BAY BY 12Z FRI AS WEAK TROUGHING CONTINUES OVER THE PACIFIC NW...AND LOW NOW OVER NB MOVES NE INTO NEWFOUNDLAND. FARTHER S...A SERIES OF WEAKER DISTURBANCES WILL PERSIST IN ARC OF ENHANCED FLOW SKIRTING IMMEDIATE N SIDE OF RIDGE. THE MOST SIGNIFICANT OF THESE IMPULSES...NOW OVER ERN SD/NE NEB...SHOULD REACH LWR MI THIS EVE AND THE MID ATLANTIC CST EARLY FRI. FEATURES WILL REMAIN WEAK AT THE SFC. NRN PART OF COLD FRONT NOW EXTENDING FROM THE UPR GRT LKS TO THE CNTRL PLNS SHOULD CONTINUE STEADILY E/SE ACROSS THE NRN APPALACHIANS/MID ATLANTIC REGION BY THE END OF THE PERIOD. THE TRAILING WRN PART OF THE BOUNDARY...HOWEVER...LIKELY WILL BECOME QSTNRY FROM SRN NEB/NW KS TO NRN IL/IND. THE FRONT WILL TO SOME EXTENT SERVE AS A FOCUS FOR POTENTIALLY STRONG TO SVR TSTMS THROUGH THE PERIOD. BUT STORM COVERAGE WILL BE LIMITED BY CONTINUING PRESENCE OF DEEP/EXPANSIVE EML. ...LWR MI/OH VLY INTO PA/NY TODAY THROUGH EARLY FRI... CAP ASSOCIATED WITH VERY WARM EML...AND RELATIVELY DRY LOW LVL AIR...SUGGESTS THAT LIKELIHOOD FOR ORGANIZED SVR TSTMS WILL REMAIN LOW ALONG/AHEAD OF COLD FRONT FROM LWR MI S/SE INTO THE OH VLY TODAY. HOWEVER...A GREATER POTENTIAL FOR DEVELOPMENT MAY BE REALIZED TNGT THROUGH EARLY FRI ALONG THE NE FRINGE OF THE EML. ELONGATION OF UPR RIDGE WILL CARRY ERN EDGE OF THE EML WELL BEYOND ITS USUAL RANGE...DISPLACING IT INTO THE UPR OH VLY/WRN MID ATLANTIC REGION. WHILE ASSOCIATED WARM MID LVL TEMPS SHOULD PROHIBIT SFC-BASED STORM DEVELOPMENT AHEAD OF THE FRONT...FRONTAL UPLIFT/POST-FRONTAL WAA/MOISTURE TRANSPORT MAY SUPPORT ELEVATED CONVECTION IN THE WAKE OF THE BOUNDARY. THESE STORMS COULD PRODUCE SVR HAIL AND POSSIBLY DMGG WIND GIVEN STEEP MID LVL LAPSE RATES/INCREASING MOISTURE ALOFT. THE MOST LIKELY AREA FOR SUCH DEVELOPMENT WILL BE OVER THE LK ERIE REGION THIS EVE...WHERE ASCENT WILL BE ENHANCED BY CONTINUED E/ESE ADVANCE OF NEB/SD IMPULSE. THE STORMS COULD SPREAD E/SE INTO ERN PA/MD BY 12Z FRI. ...CNTRL PLNS TO MID MS VLY TODAY/TNGT... STALLING SFC FRONT AND ASSOCIATED OUTFLOW BOUNDARIES WILL SERVE TO FOCUS STORM DEVELOPMENT LATER TODAY FROM THE CNTRL HI PLNS EWD INTO SRN NEB/NRN KS IN RESPONSE TO STRONG SFC HEATING. THE STORMS SHOULD BE HIGH-BASED/MULTICELLULAR GIVEN EXPECTED WIND/THERMODYNAMIC ENVIRONMENT...AND COULD YIELD ISOLD DMGG WIND GUSTS. SOME POTENTIAL ALSO WILL EXIST FOR COLD-POOL MERGERS THAT MIGHT ENHANCE SVR POTENTIAL ON A SOMEWHAT LARGER SCALE OVER NE CO/SW NEB/NW KS THIS EVE. HOWEVER...WEAK DEEP SHEAR AND MODEST NATURE OF LARGE SCALE ASCENT/NOCTURNAL LLJ SHOULD LIMIT DEGREE/EXTENT OF SVR THREAT. FARTHER E...OVER IA/WI AND NRN IL...STOUT EML SHOULD PROHIBIT SFC-BASED STORM DEVELOPMENT ALONG THE FRONT...DESPITE PRESENCE OF MORE SUBSTANTIAL BOUNDARY LAYER MOISTURE RELATIVE TO POINTS W AND E. HOWEVER...AREAS OF MOISTURE WITHIN AND ABOVE THE LOWEST PORTION OF THE EML MAY YIELD SCTD AREAS/SHORT LINES OF ACCAS/HIGH-BASED STORMS THROUGH THE DAY AHEAD OF NEB/SD UPR IMPULSE. ANY SUSTAINED STORMS THAT DO FORM IN THIS ENVIRONMENT COULD PRODUCE SVR HAIL/LOCALLY DMGG WIND GIVEN STEEP MID LVL LAPSE RATES. BUT THE LIKELIHOOD FOR SUSTAINED STORMS APPEARS TOO LOW ATTM TO WARRANT UPGRADE TO CATEGORICAL SLIGHT RISK. ..CORFIDI/GARNER.. 06/28/2012 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z CURRENT UTC TIME: 1308Z (8:08AM), RELOAD THIS PAGE TO UPDATE THE TIME 
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