SPC AC 250100
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0800 PM CDT SAT JUL 24 2010
VALID 250100Z - 251200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OH VALLEY THROUGH A
PORTION OF THE NERN STATES...
...NERN STATES THROUGH OH VALLEY...
STORMS THAT INITIATED ALONG LAKE BREEZES CONTINUE ACROSS NY AND PA.
STRONGEST STORMS INCLUDING A FEW SUPERCELLS AND LINE SEGMENTS ARE
MOVING SEWD THROUGH NRN PA. ACTIVITY IS ALSO ASSOCIATED WITH A VORT
MAX THAT CONTINUES THROUGH UPSTATE NY AND IS ACCOMPANIED BY A BELT
OF 50+ KT MID LEVEL FLOW AND A WSWLY 40+ KT LOW LEVEL JET. VWP DATA
INDICATE 0-1 KM STORM RELATIVE HELICITY OF 200-300 M2/S2 FROM NRN PA
NWD INTO NY IN ASSOCIATION WITH THE LOW LEVEL JET. THREAT FOR A
COUPLE OF TORNADOES WILL PERSIST UNTIL ABOUT 03Z MAINLY WITH STORMS
MOVING ESEWD TOWARD CNTRL PA WHERE MORE FAVORABLE LOW LEVEL SHEAR
COINCIDES WITH STRONGER CAPE. ISOLATED STRONG WIND GUSTS AND PERHAPS
AN ISOLATED TORNADO REMAIN POSSIBLE WITH STORMS MOVING THROUGH NY.
HOWEVER...AN ALREADY MARGINAL THERMODYNAMIC ENVIRONMENT ALONG WITH A
STABILIZING BOUNDARY LAYER WILL LIMIT OVERALL POTENTIAL IN THIS
AREA.
FARTHER WEST ACROSS THE OH VALLEY...STORMS CONTINUE ALONG AN E-W
ORIENTED PRE-FRONTAL BOUNDARY AS WELL AS IN ASSOCIATION WITH AN MCV
AND A MORE N-S ORIENTED BOUNDARY ACROSS WRN IND. THESE STORMS REMAIN
EMBEDDED WITHIN AN ENVIRONMENT CHARACTERIZED BY 1500-2500 J/KG
MLCAPE AND 30-40 KT EFFECTIVE SHEAR. EMBEDDED ORGANIZED STORM
STRUCTURES AND THREAT FOR ISOLATED DAMAGING WIND REMAINS POSSIBLE
THROUGH MID EVENING...BUT A GRADUAL DECREASE IS EXPECTED AS THE
BOUNDARY LAYER BEGINS TO STABILIZE.
...SERN KS THROUGH CNTRL-SRN MO AND CNTRL-SRN IL...
EXPANSIVE SQUALL LINE WITH TRAILING STRATIFORM AREA EXTENDS FROM W
CNTRL IL SWWD THROUGH CNTRL MO INTO SERN KS AND IS PROPAGATING
SLOWLY SWD. THE STORMS ARE EMBEDDED WITHIN WEAK FLOW AND VERTICAL
SHEAR WHICH WILL LIMIT POTENTIAL FOR STORM SCALE ORGANIZATION.
HOWEVER...MODEST THREAT FOR ISOLATED STRONG TO DAMAGING WIND GUSTS
WILL PERSIST THROUGH MID EVENING AS ACTIVITY MOVES SWD THROUGH THE
AXIS OF 2000-2500 J/KG MLCAPE. STORMS SHOULD BEGIN TO WEAKEN LATER
THIS EVENING WITH THE ONSET OF NOCTURNAL COOLING.
..DIAL.. 07/25/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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