Day 3 outlooks

SPC AC 080727

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0227 AM CDT SAT MAY 08 2010

VALID 101200Z - 111200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL/SRN PLAINS TO
THE MID-MS VLY...

...SYNOPSIS...
THE MID-LVL WAVE LOCATED OVER THE GRT BASIN LATE IN THE WEEKEND WILL
EJECT ACROSS THE CNTRL/SRN PLAINS AS A NEGATIVE-TILT TROUGH ON
MONDAY AS THE NEXT IMPULSE DROPS SEWD TO THE PAC NW. AT THE SFC...A
LEE LOW WILL INTENSIFY OVER ERN CO THEN MOVE ACROSS NRN KS BY MONDAY
EVENING THEN TO SRN IA BY 12Z TUESDAY. A DRYLINE WILL MIX EWD TO
THE S OF THE LOW...REACHING WRN KS AND THE TX/OK BORDER AREA BY
EARLY AFTN MONDAY...THEN INTO CNTRL KS AND WRN OK BY EVENING. TO
THE E...A WRMFNT WILL CONTINUE TO DEVELOP NWD INTO THE MID-MS VLY.

...CNTRL/SRN PLAINS TO THE MID-MS VLY...
MONDAY STILL HAS THE POTENTIAL TO BE AN ACTIVE WEATHER DAY WITH
STRONG TORNADOES AND VERY LARGE HAIL POSSIBLE...PARTICULARLY OVER
CNTRL/SCNTRL KS AND EXTREME NWRN/NCNTRL OK.

BANDS/CLUSTERS OF ELEVATED TSTMS ARE EXPECTED TO BE ONGOING EARLY
MONDAY ACROSS PORTIONS OF ERN KS/OK OWING TO A ROBUST WAA REGIME
WITHIN A BROAD 45-50 KT SSWLY LLJ. THIS ACTIVITY MAY PROVE
PROBLEMATIC FOR A NWD EXPANSION OF THE WARM SECTOR MONDAY AFTN AND
THIS UNCERTAINTY WAS THE PRIMARY REASON FOR NOT UPGRADING TO A MDT
RISK.

CONFIDENCE REMAINS SUFFICIENTLY HIGH...HOWEVER...IN THE RETURN OF
MID/UPR 60S BOUNDARY LAYER DEW POINTS E OF THE DRYLINE/TRIPLE POINT
INTO AT LEAST SWRN KS BY AFTN. DRYLINE CIRCULATION WILL DEEPEN WITH
APPROACH OF THE UPR TROUGH BY MID-AFTN AND STRONG HEATING WILL ERODE
CINH FOR TSTM INITIATION...MOSTLY LIKELY IN WRN KS. FARTHER
S...CINH WILL BE STRONGER AND LARGE SCALE FORCING COMPARATIVELY
WEAKER ACROSS WRN OK. BUT...ISOLD STORM DEVELOPMENT CANNOT BE RULED
OUT AS FAR S AS WRN OK/RED RIVER.

EFFECTIVE SHEAR IN EXCESS OF 55 KTS AND THE ORIENTATION OF VECTORS
PERPENDICULAR TO THE DRYLINE WILL STRONGLY SUPPORT SUPERCELLS. FCST
HODOGRAPHS EXHIBIT STRONGLY VEERING LOW-LEVEL WINDS WITH THE
COMPLETE VERTICAL PROFILE SIGNATURES INDICATIVE OF HISTORIC STRONG
TORNADIC CASES. VERY LARGE HAIL WILL ALSO BE POSSIBLE.

AS MENTIONED BEFORE...IT IS UNCLEAR HOW FAR N AND E THE QUALITY WARM
SECTOR WILL EXPAND. THE MAXIMUM TORNADO THREAT MAY REALISTICALLY BE
IN NARROW ZONE ACROSS SCNTRL/CNTRL KS INTO NCNTRL OK BEFORE STORMS
MOVE TOWARD A MORE STABLE LOW-LEVEL ENVIRONMENT. LATER OUTLOOKS CAN
ADDRESS THIS UNCERTAINTY.

OTHERWISE...STORMS WILL LIKELY DEVELOP INTO ONE OR MORE MCS/S AND
DEVELOP/MOVE ENE TOWARD THE MID-MS VLY OVERNIGHT WITH LARGE HAIL THE
PRIMARY THREAT.