SPC AC 280540
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1240 AM CDT MON MAR 28 2011
VALID 291200Z - 301200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CNTRL AND ERN
TX INTO THE LOWER MS VALLEY...
...SYNOPSIS...
SHORTWAVE TROUGH NOW MOVING INTO THE PACIFIC NW WILL ADVANCE SEWD
THROUGH KS/OK TUESDAY...REACHING THE MID MS VALLEY OVERNIGHT. SRN
STREAM IMPULSE JUST WEST OF BAJA CA MAY CONTINUE THROUGH SRN TX. WRN
EXTENSION OF FRONT THAT SHOULD STALL FROM NRN FL WWD THROUGH SRN TX
MONDAY WILL LIFT NWD THROUGH CNTRL TX AND LOWER MS VALLEY TUESDAY
BEFORE ACCELERATING SEWD AS NRN STREAM IMPULSE CONTINUES THROUGH THE
MID MS VALLEY.
...CNTRL AND ERN TX THROUGH THE LOWER MS VALLEY...
EARLY TUESDAY...MOIST WARM SECTOR WITH MID-UPPER 60S DEWPOINTS WILL
RESIDE SOUTH OF FRONT ACROSS S-SERN TX. THE FRONT MAY LIFT NWD
DURING THE DAY THROUGH AT LEAST CNTRL TX AND SRN PARTS OF THE LOWER
MS VALLEY. HOWEVER...NWD ADVANCE OF THIS BOUNDARY WILL BE LIMITED BY
EXPANSIVE AREA OF CP AIR ASSOCIATED WITH A LARGE SURFACE RIDGE
CENTERED OVER SRN CANADA AND EXTENDING SWD INTO LOWER MS VALLEY AND
SERN STATES. PLUME OF STEEP 7-7.5 C/KM MID LEVEL LAPSE RATES WILL
SPREAD EWD ABOVE MOISTENING WARM SECTOR RESULTING IN MODERATE
INSTABILITY...BUT ALSO A CAPPING INVERSION...ESPECIALLY ACROSS TX.
WIDESPREAD STRATUS RESULTING FROM ISENTROPIC LIFT AND WARM ADVECTION
ABOVE COOL BOUNDARY LAYER WILL LIKELY DEVELOP FROM MUCH OF ERN TX
INTO THE LOWER MS VALLEY.
A FEW ELEVATED STORMS SHOULD BE IN PROGRESS WITHIN WARM ADVECTION
REGIME FROM OK INTO AR WITH A THREAT FOR HAIL. ADDITIONAL STORMS MAY
DEVELOP FARTHER SOUTH WITHIN THE ZONE OF ISENTROPIC LIFT AND ALONG
ERN FRINGE OF WARMER EML PLUME ACROSS THE LOWER MS VALLEY REGION.
ACTIVITY DEVELOPING NEAR THE WARM FRONT COULD BE CLOSE TO
SURFACE BASED...BECOMING ELEVATED AS IT SPREADS NEWD. DESPITE THE
MOSTLY ELEVATED NATURE OF THE CONVECTION...EFFECTIVE SHEAR FROM
35-45 KT...700-500 MB LAPSE RATES FROM 7-8 C/KM AND MODERATE MUCAPE
WILL SUPPORT A THREAT OF ISOLATED LARGE HAIL WITH THE STRONGER
STORMS.
STRONGER FORCING FOR ASCENT WITH PROGRESSIVE SHORTWAVE TROUGH MOVING
THROUGH KS AND MO WILL REMAIN IN COOL SECTOR...SUGGESTING LOW LEVEL
RESPONSE AND WINDS IN WARM SECTOR WILL REMAIN WEAK DURING THE DAY.
THIS IN CONJUNCTION WITH PRESENCE OF CAP MIGHT LIMIT STORM COVERAGE
ACROSS TX AND COULD SERVE AS A LIMITING FACTOR. STORM DEVELOPMENT
WILL PROBABLY BE DELAYED UNTIL DEEPER BAROCLINIC ZONE ADVANCES SEWD
WITH BEST CHANCE FOR INITIATION FROM NERN THROUGH S-CNTRL TX. WHILE
L0W-LEVEL SHEAR WILL LIKELY REMAIN RELATIVELY WEAK IN THIS
REGION...0-6 KM SHEAR FROM 35-45 KT WILL BE SUFFICIENT FOR A FEW
ORGANIZED STORMS WITH ISOLATED LARGE HAIL AND DAMAGING WIND THE MAIN
THREATS. ACTIVITY SHOULD DEVELOP SEWD INTO SERN TX AND THE LOWER MS
VALLEY OVERNIGHT.
..DIAL.. 03/28/2011
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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