CATEGORICAL OUTLOOK
TORNADO OUTLOOK
WIND OUTLOOK
HAIL OUTLOOK
SPC AC 091257 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 AM CDT SAT JUN 09 2012 VALID 091300Z - 101200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN PLNS/UPR MS VLY... ...SYNOPSIS... NRN RCKYS/NRN GRT BASIN UPR LOW/TROUGH WILL CONTINUE E TO THE NRN HI PLNS/CNTRL RCKYS THIS PERIOD AS DOWNSTREAM RIDGE AMPLIFIES OVER THE UPR GRT LKS/OH VLY. ELSEWHERE...WEAK UPR LOW NOW CENTERED ALONG THE WRN LA CST EXPECTED TO EDGE NWD INTO THE LWR MS VLY AND FURTHER ELONGATE N-S. AT LWR LVLS...SFC LOW NOW IN WRN ND SHOULD MOVE NNE TO NEAR WINNIPEG BY LATE TNGT...WHILE A NEW LOW FORMS OVER SE WY/NE CO IN RESPONSE TO UPR IMPULSE ROUNDING BASE OF RCKYS/GRT BASIN UPR LOW. COLD FRONT EXTENDING SSW FROM THE ND LOW SHOULD ADVANCE ONLY SLOWLY EWD TODAY...BEFORE ACCELERATING ESEWD TNGT/EARLY SUN AS THE UPR IMPULSE REACHES WY/CO. TSTMS...SOME POSSIBLY SVR...MAY ACCOMPANY THE WAA ZONES ASSOCIATED WITH BOTH SFC LOWS TODAY THROUGH TNGT. THE RISK FOR A FEW STRONG TO POSSIBLY SVR STORMS ALSO WILL EXIST WITH AREAS OF WEAKER WAA ALONG THE CNTRL GULF CST AND OVER THE NORTHEAST. ...DAKOTAS/NW MN TODAY THROUGH EARLY SUN... ON-GOING SLIGHTLY ELEVATED SQLN IN N CNTRL ND MAY PERSIST THROUGH LATER THIS MORNING AS IT CONTINUES GENERALLY EWD. NEW DEVELOPMENT PREFERENTIALLY MAY OCCUR ON SRN END OF SYSTEM...BUT THE SQLN SHOULD AT LEAST TEMPORARILY WEAKEN TOWARD MIDDAY AS STOUT EML BUILDS NNE ACROSS REGION. RENEWED STORM DEVELOPMENT SHOULD OCCUR ALONG THE COLD FRONT AS SFC HEATING/CONVERGENCE OVERCOME EML LATER THIS AFTN INTO TNGT FROM SRN MB SWD INTO ND. EML CAP MAY KEEP ACTIVITY FAIRLY ISOLD S OF NERN ND. THIS NOTION IS SUPPORTED BY THE FACT THAT THE LATEST SHORT-RANGE MODELS REMAIN TOO MOIST IN THE LWR LVLS...WITH SFC DEWPOINTS EXPECTED TO REMAIN IN THE UPR 50S TO LOW 60S F... RATHER THAN IN THE UPR 60S. NEVERTHELESS...STEEP LOW TO MID LVL LAPSE RATES WILL FAVOR STRONG UPDRAFTS/LARGE HAIL WITH ANY SUSTAINED UPDRAFTS THAT DO BREACH CAP GIVEN THE STRONGLY SHEARED ENVIRONMENT. FARTHER SSW...SFC HEATING MAY SUPPORT ISOLD HIGH-BASED STORMS IN DEEPLY-MIXED ENVIRONMENT ALONG LEE TROUGH/DRY LINE IN WRN SD/WRN NEB/FAR ERN WY. THESE MAY YIELD A LOCALLY DMGG WIND GUST OR TWO. A MORE SUBSTANTIAL SVR THREAT MAY DEVELOP THIS EVE THROUGH TNGT ALONG THE LEE TROUGH/COLD FRONT OVER WRN AND CNTRL SD AS NEW STORMS FORM IN RESPONSE TO INCREASING ASCENT AHEAD OF APPROACHING UPR IMPULSE. COUPLED WITH INCREASING DEEP SHEAR AND STRENGTHENING LLJ/MOISTURE INFLOW...A CLUSTER OR TWO OF ELEVATED STORMS WITH HAIL AND POSSIBLY DMGG WIND MAY PERSIST INTO EARLY SUN. ...PA/NY/NJ THIS AFTN... WEAK WAA ON ERN EDGE OF AMPLIFYING RIDGE WILL FOCUS OVER PARTS OF NY...PA...AND NJ THIS AFTN/EVE. ALTHOUGH WEAK HEIGHT RISES WILL TO SOME EXTENT OFFSET ASSOCIATED DESTABILIZATION...SFC HEATING ON SRN FRINGE OF WAA STRATIFORM CLOUD FIELD SHOULD SUPPORT ISOLD TO POSSIBLY SCTD TSTM DEVELOPMENT BENEATH MODERATE /30-40 KT/ NWLY MID LVL FLOW. AS IN THE NRN PLNS...GUIDANCE APPEARS TO BE OVERESTIMATING LOW LVL MOISTURE PER CURRENT SFC OBS. BUT SETUP MAY NEVERTHELESS YIELD A FEW STORMS WITH MARGINALLY SVR HAIL/WIND GIVEN RELATIVELY STEEP MID LVL LAPSE RATES. THE CONVECTION SHOULD BE MAINLY DIURNAL AND WEAKEN WITH SUNSET. ...CNTRL/ERN GULF CST LATER TODAY THROUGH EARLY SUN... WAA/MOISTURE TRANSPORT WILL INCREASE THROUGH THE PERIOD ALONG THE CNTRL GULF CST AS LOW LVL FLOW STRENGTHENS IN ASSOCIATION WITH ELONGATING UPR LOW/TROUGH. THIS WILL LEAD TO CONSIDERABLE COVERAGE OF SHOWERS/STORMS...ESPECIALLY INVOF DIFFUSE WARM FRONT ATTM EXTENDING FROM EXTREME SRN LA ESE INTO THE NERN GULF. WHILE THIS WILL HINDER INLAND PENETRATION OF LOW LVL DESTABILIZATION...ASSOCIATED INCREASE IN LOW LVL SHEAR AND MOISTURE /PW AROUND 2 INCHES/ MAY PROVE SUFFICIENT TO SUPPORT A LOW CONDITIONAL RISK FOR A TORNADO OR TWO...AND/OR FOR LOCALLY DMGG WIND. ..CORFIDI/LEITMAN.. 06/09/2012 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z CURRENT UTC TIME: 1324Z (8:24AM), RELOAD THIS PAGE TO UPDATE THE TIME 
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