SPC AC 300053
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0653 PM CST SAT JAN 29 2011
VALID 300100Z - 301200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM S-CNTRL THROUGH SERN TX...
...S-CNTRL THROUGH SERN TX...
TIMING AND EXTENT OF CONVECTIVE INITIATION ARE THE MAIN UNCERTAINTY
FOR THIS FORECAST. EVENING RAOB DATA FROM BROWNSVILLE...DEL RIO AND
CORPUS CHRISTI INDICATE AN EML HAS ADVECTED THROUGH THE MOISTENING
WARM SECTOR ACROSS SRN THROUGH S-CNTRL TX...EFFECTIVELY CAPPING THE
BOUNDARY LAYER TO DEEP CONVECTION. RUC ANALYSIS DATA AND WV IMAGERY
INDICATE SEVERAL WEAKER HIGH LEVEL VORTICITY MAXIMA EMBEDDED WITHIN
THE SUBTROPICAL JET ARE MOVING THROUGH SWRN AND CNTRL TX AHEAD OF
THE MAIN SHORTWAVE TROUGH THAT IS STILL LOCATED OVER NRN MEXICO. THE
VERTICAL MOTION ACCOMPANYING THESE FEATURES IS CONTRIBUTING TO
ISOLATED HIGH BASED CONVECTION ROOTED NEAR 700 MB ABOVE THE CAPPING
LAYER. FORCING ASSOCIATED WITH LEAD VORTICITY MAXIMA IS UNLIKELY TO
BECOME DEEP ENOUGH TO ERODE THE CAP.
DEEPER CONVECTION WILL BECOME MORE LIKELY LATE TONIGHT INTO EARLY
SUNDAY FROM S-CNTRL THROUGH SERN TX AS THE STRONGER VORT MAX OVER
NRN MEXICO ADVANCES THROUGH S-CNTRL TX. UNCERTAINTY REGARDING THE
DEPTH AND STRENGTH OF THIS VERTICAL MOTION AND DISPERSIVE MODEL
SOLUTIONS LOWERS CONFIDENCE IN THE TIMING AND EXTENT OF INITIATION.
IT IS POSSIBLE THAT MORE ROBUST STORMS WILL NOT FORM UNTIL AFTER 10Z
WHEN ASCENT INCREASES ACROSS SERN TX INTO THE LOWER MS VALLEY ALONG
THE ERN PERIPHERY OF THE EML. THE THERMODYNAMIC ENVIRONMENT WITH
STEEP LAPSE RATES AND COLD AIR ALOFT...A MOISTENING BOUNDARY
LAYER...AND EFFECTIVE SHEAR SUFFICIENT FOR UPDRAFT ROTATION WILL
POSE A THREAT FOR LARGE HAIL SHOULD STORMS DEVELOP. WILL MAINTAIN
15% PROBABILITIES FOR MAINLY HAIL...BUT OVERALL THREAT REMAINS
CONDITIONAL UPON CAP EROSION AND INITIATION OF DEEPER STORMS.
..DIAL.. 01/30/2011
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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