SPC AC 112001
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0301 PM CDT SUN MAR 11 2007
VALID 112000Z - 121200Z
...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS S-CENTRAL...CENTRAL
AND SW TX...
...SYNOPSIS...
MOISTURE CHANNEL IMAGERY SHOWS MID/UPPER LEVEL CYCLONE CONTINUING TO
DIG SWD ACROSS CENTRAL/SRN NM...BECOMING MORE CUT-OFF FROM NRN
STREAM WLYS WITH TIME. AS THIS PROCESS CONTINUES...EXPECT MOTION OF
LOW ALOFT TO BECOME SLOWER AND MORE ERRATIC...WITH GENERAL DRIFT
TOWARD GUADALUPE MOUNTAINS REGION.
AT SFC AT 19Z...COMPLEX ARRAY OF BOUNDARIES IS ANALYZED...PRIMARY
ONES BEING AS FOLLOWS. SYNOPTIC COLD FRONT EXTENDS FROM N-CENTRAL
OK SWWD ACROSS EXTREME SERN NM...AND SHOULD CONTINUE TO MOVE SLOWLY
SWD E OF UPPER LOW. OUTFLOW BOUNDARY IS MOVING SWD ACROSS
GLASSCOCK/UPTON/NRN REEVES/PECOS COUNTIES...AND SHOULD DECELERATE
THROUGH REMAINDER AFTERNOON. DRYLINE IS ANALYZED FROM MESOLOW NEAR
FST...SWD INTO ERN PORTIONS BIG BEND AREA...AND SHOULD REMAIN
QUASISTATIONARY. ANOTHER OUTFLOW BOUNDARY INTERSECTS THE PREVIOUS
ONE OVER UPTON COUNTY AND ARCS EWD AND NEWD AROUND SRN/ERN EDGE OF
W-CENTRAL TX PRECIP PLUME...TO MESOLOW S SPS. QUASISTATIONARY
BAROCLINIC ZONE EXTENDS EWD FROM THAT LOW ROUGHLY ALONG RED RIVER TO
NEAR PRX...THEN ESEWD NEAR AR/LA BORDER.
...CENTRAL/SW TX...
GREATEST SFC-BASED SVR POTENTIAL SHOULD REMAIN S AND SE OF OUTFLOW
BOUNDARIES...WHERE STRONGEST HEATING WILL CONTINUE BOTH NEAR DRYLINE
AND ON HIGHER TERRAIN OF NRN COAHUILA. TSTMS FORMING IN LATTER AREA
MAY MOVE ENEWD ACROSS RIO GRANDE WITH POTENTIAL FOR SVR. ISOLATED
TO WIDELY SCATTERED TSTMS ARE BUILDING RAPIDLY S FST ALONG DRYLINE
AND INVOF JCT...WITH TCU EVIDENT IN VIS IMAGERY FARTHER SW INTO NRN
MEX MOUNTAINS. SIGNIFICANT-HAIL AREA IS INTRODUCED JUST AHEAD OF
DRYLINE AND SEWD ALONG RIO GRANDE...BASED ON FAVORABLE DEEP-LAYER
SHEAR PROFILES FOR SUSTAINED/DISCRETE SUPERCELLS S OF OUTFLOW
BOUNDARY...FAVORABLY STEEP LOW-MIDLEVEL LAPSE RATES...AND NARROW
CORRIDOR OF ENHANCED BUOYANCY CORRESPONDING CLOSELY TO SFC THETAE
AXIS. REF WW 57 AND ASSOCIATED MESOSCALE DISCUSSIONS FOR LATEST
NEAR-TERM FORECAST INFO ON SW TX REGION. EXPECT UPSCALE GROWTH INTO
ONE OR TWO MCS ACROSS S-CENTRAL/SW TX THIS EVENING AND
TONIGHT...WITH POTENTIAL FOR SVR CONTINUING MUCH OF TONIGHT.
...N-CENTRAL TX AND SRN OK...
LAPSE RATES WILL CONTINUE TO WEAKEN WITH EWD AND NEWD EXTENT
ALONG/AHEAD OF SWRN/CENTRAL TX OUTFLOW BOUNDARY...AND OVER N-CENTRAL
TX/SRN OK. SFC PATTERN INITIALLY APPEARS FAVORABLE FOR SVR
DEVELOPMENT WITH MESOLOW...OUTFLOW BOUNDARY INTERSECTION...PRESSURE
FALLS E OF MESOLOW...AND BACKED WINDS INVOF RED RIVER BOUNDARY. SFC
VORTICITY SHOULD REMAIN MAXIMIZED INVOF MESOLOW...AND MRGLLY SVR
HAIL...BRIEF TORNADO OR WET MICROBURST CANNOT BE RULED OUT WITH ANY
ACTIVITY DEVELOPING OVER THIS AREA. HOWEVER...CONSIDERABLE PROBLEMS
REMAIN WITH THERMODYNAMICS -- SFC AND ALOFT. SFC HEATING/MIXING HAS
KEPT DEW POINTS LOW 50S IN POCKETS E OF SFC LOW...BENEATH VERY WEAK
MIDLEVEL LAPSE RATES. MLCAPES SHOULD REMAIN AROUND 500 J/KG FOR A
FEW MORE HOURS BEFORE DARK...IN NARROW N-S CORRIDOR IMMEDIATELY
AHEAD OF ONGOING NWRN/CENTRAL TX PRECIP PLUME. SVR THREAT APPEARS
TOO CONDITIONAL AND DISORGANIZED TO BOOST PROBABILITIES PAST
CATEGORICAL OUTLOOK THRESHOLDS.
..EDWARDS.. 03/11/2007
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
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