SPC AC 110558
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1158 PM CST WED JAN 10 2007
VALID 121200Z - 131200Z
...NO SVR TSTM AREAS FORECAST...
IN THE SOUTHERN BRANCH OF SPLIT POLAR WESTERLIES...A VIGOROUS
DIGGING IMPULSE WILL LIKELY BOTTOM OUT ACROSS THE SOUTHERN GREAT
BASIN/LOWER COLORADO VALLEY LATE TONIGHT OR EARLY FRIDAY. MUCH
UNCERTAINTY REMAINS CONCERNING EVENTUAL EASTWARD ACCELERATION OUT OF
THE SOUTHWESTERN STATES. BUT...GUIDANCE CONTINUES TO INDICATE THAT
SIGNIFICANT SURFACE CYCLOGENESIS WILL NOT INITIATE ALONG THE SHARP
COLD FRONT TO THE LEE OF THE ROCKIES THROUGH AT LEAST THE END OF
THIS FORECAST PERIOD.
MODELS APPEAR TO BE TRENDING A BIT FASTER WITH SURFACE-BASED COLD
INTRUSION THROUGH THE PLAINS. AND...THE FRONT IS NOW PROGGED TO
ADVANCE ACROSS THE RED RIVER VALLEY INTO NORTHERN AND WEST CENTRAL
TEXAS BY LATE FRIDAY AFTERNOON. AT THE SAME TIME...A MOIST RETURN
FLOW WILL PERSIST OFF THE WESTERN GULF OF MEXICO...AIDED BY A 30-40
KT SOUTHERLY LOW-LEVEL JET AROUND THE WESTERN PERIPHERY OF A
SUBTROPICAL RIDGE. THIS WILL CONTRIBUTE TO INCREASING CONVECTIVE
POTENTIAL ACROSS THE SOUTHERN PLAINS AND OZARK PLATEAU...MOSTLY
FRIDAY EVENING INTO EARLY SATURDAY. BUT...NEAR MOIST ADIABATIC
LAPSE RATES ASSOCIATED WITH AN ELEVATED PACIFIC MOIST PLUME WILL
LIKELY CONTINUE TO LIMIT MAGNITUDE OF DESTABILIZATION AND SEVERE
THREAT.
...TEXAS...
ALTHOUGH DESTABILIZATION WILL BE WEAK...THIS PROBABLY WILL BECOME
BASED IN THE BOUNDARY LAYER AHEAD OF COLD FRONT ACROSS PARTS OF
CENTRAL INTO NORTHEAST TEXAS LATE FRIDAY AFTERNOON AND EVENING.
FORCING ASSOCIATED WITH THE SUBTROPICAL STREAM IS NOW A BIT MORE
UNCERTAIN...BUT STRONG DEEP LAYER SHEAR BENEATH THE SUBTROPICAL JET
AXIS WILL BE FAVORABLE FOR SUPERCELLS IN THE PRESENCE OF WEAK
LOW-LEVEL WARM ADVECTION. THUS...AT LEAST A LOW RISK FOR SEVERE
STORMS APPEARS TO EXIST...ESPECIALLY GIVEN THE POTENTIAL OF
FAVORABLY LARGE LOW-LEVEL HODOGRAPHS FOR POSSIBLE TORNADIC
DEVELOPMENT.
A BIT FARTHER TO THE WEST NORTHWEST...NORTH OF THE SUBTROPICAL JET
...CAPE IS NOT LIKELY TO BE MUCH GREATER AHEAD OF FRONT ACROSS THE
TEXAS SOUTH PLAINS. BUT...SLIGHTLY COOLER/DRIER AIR ALOFT MAY
CONTRIBUTE TO A BIT STRONGER CONVECTIVE INSTABILITY BENEATH WEAKLY
DIFLUENT UPPER FLOW REGIME. WITH DEEP LAYER SHEAR SUFFICIENT FOR
SUPERCELLS...SOME HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE
LIMITS IS POSSIBLE IN ISOLATED CONVECTIVE DEVELOPMENT.
..KERR.. 01/11/2007
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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