CATEGORICAL OUTLOOK
TORNADO OUTLOOK
WIND OUTLOOK
HAIL OUTLOOK
SPC AC 081258 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 AM CDT FRI JUN 08 2012 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NERN STATES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPR MS VLY/UPR GRT LKS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER WRN PARTS OF THE NRN PLNS... ...SYNOPSIS... PROGRESSIVE TROUGH/RIDGE/TROUGH PATTERN WILL PREVAIL OVER THE NRN HALF OF THE CONUS THIS PERIOD...WITH WEAK FLOW ACROSS THE SRN TIER. CLOSED LOW OFF VANCOUVER ISLAND SHOULD CONTINUE SE INTO ORE BY EARLY SAT AS A SERIES OF WEAK DOWNSTREAM DISTURBANCES TRACK NE ACROSS ID AND MT. FARTHER E...SHORTWAVE TROUGH NOW OVER SRN SK/ND LIKELY WILL WEAKEN AS IT SHEARS ESE IN CONFLUENT FLOW OVER WRN ONT/LK SUPERIOR...WHILE IMPULSE NOW ENTERING SW QUE AMPLIFIES SE INTO ERN NEW ENGLAND. DIURNALLY ENHANCED TSTMS...SOME POSSIBLY SVR...WILL ACCOMPANY THE SHORTWAVE FEATURES OVER PARTS OF THE NRN PLNS...THE UPR MS VLY...AND THE NERN STATES. ...NERN U.S. THIS AFTN/EVE... INCREASING LARGE SCALE ASCENT/UPR DIFFLUENCE WILL OVERSPREAD UPSTATE NY AND NRN NEW ENGLAND TODAY AHEAD OF UPR IMPULSE AMPLIFYING SEWD FROM QUE. WHILE THIS WILL LEAD TO AN INCREASE IN HIGH-LVL CLOUDS...APPROACH OF SYSTEM ALSO WILL BE ACCOMPANIED BY STEEPENING MID LVL LAPSE RATES. LOW LVL CONVERGENCE WILL REMAIN WEAK...AND MOISTURE COMPARATIVELY SPARSE. BUT COMBINATION OF INCREASING ASCENT...STEEPENING MID LVL LAPSE RATES...AND SFC HEATING SHOULD SUPPORT DEVELOPMENT OF A SHORT BANDS/SMALL CLUSTERS OF STORMS OVER NRN/ERN NY AND WRN/NRN NEW ENGLAND BY EARLY TO MID AFTN. 30-40 KT NWLY MID LVL FLOW SHOULD PROVE SUFFICIENT FOR A FEW SUSTAINED STORMS/MULTICELLS WITH A RISK FOR SVR WIND/HAIL. WHILE BOTH WINDS AND ASCENT WILL CONTINUE TO INCREASE AFTER SUNSET...THE STORMS SHOULD DIMINISH WITH ONSET OF DIURNAL COOLING. ...UPR MS VLY/UPR GRT LKS THIS AFTN INTO TNGT... WEAK WAA/MOISTURE TRANSPORT WILL PREVAIL OVER NE MN...WI...AND UPR MI TODAY AS SK/ND UPR IMPULSE SHEARS ESE TOWARD ONT. IN WAKE OF EARLY DAY ELEVATED WAA CONVECTION/STORMS...SFC HEATING...MOISTURE INFLOW...AND GLANCING INFLUENCE OF UPR TROUGH SHOULD SUPPORT NEW STORM DEVELOPMENT THIS AFTN GIVEN ABSENCE OF AN APPRECIABLE EML. 30-40 KT SWLY FLOW AT 850 MB VEERING TO NW WINDS OF SIMILAR SPEEDS AT MID LVLS WILL BE FAVORABLE FOR SUSTAINED STORMS/SUPERCELLS. CURRENT SFC OBS AND PW DATA SUGGEST...HOWEVER...THAT WARM SECTOR MOISTURE WILL REMAIN COMPARATIVELY LIMITED FOR THE TIME OF YEAR...WITH SFC DEWPOINTS LIKELY TO AVERAGE IN THE UPR 50S TO LOW 60S F. AS A RESULT...HAIL AND LOCALLY DMGG WIND SHOULD BE THE MAIN SVR THREATS. TORNADO OR TWO COULD...HOWEVER...OCCUR...ESPECIALLY IN NE MN AND NW WI. THE STORMS LIKELY WILL EVOLVE INTO A CLUSTER OVER NRN MI THIS EVE...WITH A DIMINISHING THREAT FOR SVR. ...MT/WRN ND THIS AFTN INTO TNGT... STRONG HEATING WILL OCCUR OVER THE NRN HI PLNS TODAY...ESPECIALLY FROM ERN MT INTO WRN ND/NW SD. MID LVL WINDS WILL INCREASE AND BACK ACROSS MT TODAY...DOWNSTREAM FROM MAIN UPR LOW/TROUGH MOVING TOWARD ORE. THIS PATTERN WILL STRENGTHEN LEE SFC LOW OVER THE NRN HI PLNS AND MAINTAIN LOW LVL ELY FLOW/MOISTURE TRANSPORT OVER CNTRL/ERN MT AHEAD OF ASSOCIATED COLD FRONT. FOR THIS REASON...AND WITH SFC HEATING...EXPECT THAT LOW LVL BUOYANCY WILL DEVELOP SUFFICIENTLY FAR W TO SUPPORT STRONG TSTM DEVELOPMENT JUST E OF THE MT RCKYS BY MID-LATE AFTN. THESE STORMS SHOULD STRENGTHEN AND MOVE/DEVELOP E INTO ERN MT THIS EVE...WHERE GREATER INSTABILITY AND LOW LVL SHEAR WILL EXIST...POSING A RISK FOR SVR HAIL...HIGH WIND...AND POSSIBLY A COUPLE TORNADOES. SUSTAINED WAA/MOISTURE TRANSPORT OVER ERN MT SHOULD FAVOR DEVELOPMENT OF AN MCS OR TWO OVER THE REGION TNGT. THESE SHOULD MOVE MAINLY E INTO WRN ND LATER TNGT/EARLY SAT...WITH HAIL AND LOCALLY DMGG WIND THE MAIN SVR THREATS. ..CORFIDI/LEITMAN.. 06/08/2012 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z CURRENT UTC TIME: 1316Z (8:16AM), RELOAD THIS PAGE TO UPDATE THE TIME 
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