SPC AC 080530
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1130 PM CST WED FEB 07 2007
VALID 081200Z - 091200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
OVERALL UPPER AIR PATTERN ACROSS CONUS WILL CONTINUE TO BE
CHARACTERIZED BY STABLE SYNOPTIC CONFIGURATION OF LARGE/COLD
CYCLONIC GYRE OVER HUDSON BAY AND NRN QUE...DOWNSTREAM FROM
QUASISTATIONARY RIDGE OVER NWRN MEX...WRN CONUS AND BC. SERIES OF
MOSTLY WEAK/LOW-AMPLITUDE SHORTWAVES ARE PROGGED TO TRAVERSE BOTH
NRN AND SRN BRANCHES OF THIS FLOW THROUGH PERIOD. ONE OF
THESE...NOW MOVING INLAND NRN CA/ORE...IS EXPECTED TO DEAMPLIFY AS
IT PENETRATES MEAN RIDGE POSITION EARLY IN PERIOD. WEAKENED
PERTURBATION THEN SHOULD ACCELERATE ESEWD FROM CENTRAL ROCKIES
TOWARD OZARKS...ENTERING SRN RIM OF CYCLONIC FLOW ASSOCIATED WITH
ERN CANADIAN VORTEX. ANOTHER TROUGH -- NOW EVIDENT IN MOISTURE
CHANNEL IMAGERY OFFSHORE CENTRAL/SRN BAJA-- IS POORLY DEPICTED BY
ALL AVAILABLE MODELS...AND MAY MOVE ENEWD OVER NRN MEX AND S TX LATE
IN PERIOD.
AT SFC...COLD FRONT NOW MOVING SWD ACROSS CENTRAL/WRN TX IS EXPECTED
TO MOVE OFFSHORE UPPER TX COAST AROUND 9/6Z AND SLOWLY SWD THROUGH
S-CENTRAL TX. WEAK FRONTAL-WAVE/LEE-SIDE LOW MAY FORM ALONG THIS
BOUNDARY N GENERAL VICINITY LRD BY 9/12Z.
...S TX TO WRN LA...
PLUME OF LOW LEVEL WAA AND ELEVATED MOISTURE TRANSPORT IS FCST TO
STRENGTHEN THROUGHOUT PERIOD ACROSS PORTIONS NERN MEX...S TX AND
LA...N OF SFC FRONTAL ZONE. THIS SHOULD OCCUR BENEATH STEEP
MIDLEVEL LAPSE RATES OF AROUND 7-8 DEG C/KM THAT WILL CONTINUE TO
CHARACTERIZE ELEVATED MIXED LAYER ADVECTED ENEWD OFF MEX
PLATEAU...PER LATEST AND FCST DRT SOUNDINGS. MIDLEVEL LAPSE RATES
ALSO MAY BE MAINTAINED OR SLIGHTLY ENHANCED AHEAD OF EJECTING BAJA
PERTURBATION.
SUFFICIENT MOISTENING ABOVE SFC IS EXPECTED OVERNIGHT THURSDAY INTO
PRE-DAWN HOURS FRIDAY MORNING TO GENERATE ELEVATED MUCAPES NEAR 1000
J/KG OVER S-CENTRAL TX...TRENDING WEAKER ENEWD TOWARD WRN LA. MAIN
UNCERTAINTY ATTM INVOLVED STRENGTH OF CAPPING JUST ABOVE ZONE OF
STRONGEST ISENTROPIC ASCENT AND MOISTENING...AND AT BOTTOM OF
ELEVATED MIXED LAYER. THIS POTENTIALLY MAY PREVENT DEEP MOIST
CONVECTION ALTOGETHER. HOWEVER...CAPPING APPEARS WEAK ENOUGH IN
SOME PROGGED SOUNDINGS...IN CONCURRENCE WITH ENHANCED TSTM
PROBABILITIES FROM SREF GUIDANCE...TO SUPPORT AT LEAST MRGL GEN
THUNDER PROBABILITIES ATTM.
..EDWARDS.. 02/08/2007
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
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