SPC AC 150537
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1237 AM CDT SUN OCT 15 2006
VALID 151200Z - 161200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE TX COASTAL
AREA INTO SRN LA...
...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SERN NM INTO WRN
TX...
...SYNOPSIS...
UPPER LOW CURRENTLY OVER AZ SHOULD ADVANCE EWD INTO ERN NM BY SUNDAY
NIGHT AS AN UPSTREAM IMPULSE AMPLIFIES INTO THE PACIFIC NW. THE GFS
IS A LITTLE FASTER THAN THE NAM IN EJECTING THIS SRN STREAM WAVE.
POTENTIAL WILL ALSO EXIST FOR WEAKER IMPULSES TO EJECT NEWD AHEAD OF
MAIN UPPER TROUGH. COASTAL FRONT OVER THE WRN GULF WILL LIFT NWD
THROUGH SERN TX INTO SRN LA SUNDAY AND SUNDAY NIGHT AS A STRONG SLY
LOW LEVEL JET DEVELOPS IN ADVANCE OF THE UPPER TROUGH.
...SERN TX THROUGH SRN LA...
LOW LEVEL DEWPOINTS IN THE LOWER 70S OVER S TX WILL ADVECT NWD INTO
PARTS OF SERN TX AND SRN LA SUNDAY AND SUNDAY NIGHT S OF RETREATING
WARM FRONT. HOWEVER...INSTABILITY SHOULD REMAIN LIMITED DUE TO MOIST
ADIABATIC PROFILES AND WIDESPREAD CLOUDS AND RAIN. SBCAPE FROM 500
TO 1000 J/KG WILL BE POSSIBLE AS LOW 70S DEWPOINTS ADVECT INLAND S
OF RETREATING FRONT. SLY LOW LEVEL JET IS FORECAST TO STRENGTHEN TO
IN EXCESS OF 50 KT OVER ERN TX SUNDAY AND SHIFT INTO LA SUNDAY NIGHT
WITHIN ZONE OF HEIGHT FALLS DOWNSTREAM FROM UPPER TROUGH.
DIFFERENCES EXIST BETWEEN THE NAM AND GFS IN HANDLING THE LOW LEVEL
MASS FIELDS...WITH THE GFS BEING WEAKER AND DISPLACED FARTHER EAST
WITH ITS LOW LEVEL JET. HOWEVER...OVERALL PATTERN WOULD SUGGEST 0-1
KM HODOGRAPHS MAY BECOME SUPPORTIVE OF LOW LEVEL MESOCYCLONES FROM
SERN TX COAST INTO SRN LA WITHIN A MOIST LOW LEVEL THERMODYNAMIC
ENVIRONMENT. CONVECTION WILL CONTINUE TO SPREAD NWD INTO SERN TX AND
SRN LA SUNDAY AND SUNDAY NIGHT. POTENTIAL WILL EXIST FOR ISOLATED
EMBEDDED SUPERCELLS WITHIN THE LARGER AREA OF CONVECTION AS LOW
LEVEL WIND FIELDS STRENGTHEN...ESPECIALLY IF POCKETS OF HEATING CAN
DEVELOP. MAIN THREAT WILL BE ISOLATED TORNADOES AND POSSIBLY
DAMAGING WIND GUSTS. MARGINAL THERMODYNAMIC PROFILES WILL REMAIN THE
PRIMARY LIMITING FACTOR.
...NM INTO FAR WRN TX...
STEEPER MID LEVEL LAPSE RATES SHOULD SPREAD EWD THROUGH NM INTO FAR
W TX ABOVE LOW LEVEL DEWPOINTS IN THE UPPER 50S TO LOWER 60S AS THE
UPPER TROUGH ADVANCES EWD. SATELLITE IMAGERY SUGGESTS AN UPPER LEVEL
DRY SLOT COULD SHIFT INTO PARTS OF ERN NM AND WRN TX AHEAD OF MAIN
VORT MAX DURING THE AFTERNOON. HOWEVER...WITH LOW LEVEL FLOW
EXPECTED TO REMAIN WEAK IN THIS REGION...LOW CLOUDS COULD BE SLOW TO
MIX OUT. WHERE POCKETS OF HEATING CAN DEVELOP MLCAPE AROUND 1000
J/KG WILL BE POSSIBLE. IF SUFFICIENT DESTABILIZATION OCCURS...STORMS
MAY INTENSIFY WITHIN ZONE OF CVA FROM NM INTO WRN TX DURING THE
AFTERNOON AND EARLY EVENING. VERTICAL WIND PROFILES WILL WITH DEEP
LAYER SHEAR FROM 50 TO 60 KT WILL SUPPORT SUPERCELL STORMS WITH
LARGE HAIL THE PRIMARY THREAT.
..DIAL.. 10/15/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
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