SPC AC 140725
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0125 AM CST SAT NOV 14 2009
VALID 161200Z - 171200Z
...SYNOPSIS...
PRIMARY UPPER AIR FEATURE FOR THIS PERIOD WILL EVOLVE FROM SHORTWAVE
TROUGH...NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER INTERIOR PAC
NW REGION. THIS PERTURBATION WILL STRENGTHEN AS IT DIGS SEWD ACROSS
4-CORNERS AND SRN HIGH PLAINS REGIONS THROUGH DAY-2...YIELDING LARGE
CYCLONE CENTERED INVOF ERN TX PANHANDLE BY 16/12Z. THIS LOW THEN
SHOULD MOVE EWD ACROSS OK...DECELERATING TO QUASISTATIONARY AND
BECOMING TEMPORARILY CUT OFF FROM NRN HEMISPHERIC WLYS AS RIDGING
BUILDS ACROSS UPPER MS VALLEY AND DAKOTAS.
MEANWHILE...SFC COLD FRONT -- NOW EVIDENT FROM LS TO ERN KS TO OK
PANHANDLE -- IS FCST TO EXTEND FROM S-CENTRAL TX NEWD ACROSS
ARKLATEX REGION INTO WEAK FRONTAL-WAVE LOW INVOF SWRN AR. BY
17/00Z...FRONT SHOULD MOVE WELL OFFSHORE TX COAST...WHILE MOVING
MORE SLOWLY EWD ACROSS LA AND SRN AR...S OF FRONTAL-WAVE LOW.
...SE TX...LA...SRN AR...
BAND OF CONVECTION...INCLUDING WIDELY SCATTERED TO SCATTERED
TSTMS...IS EXPECTED INVOF FRONT AT BEGINNING OF PERIOD...SHIFTING
EWD OVER SE TX AND ARKLATEX REGIONS DURING REMAINDER MORNING. MUCH
OF THIS ACTIVITY MAY BE ROOTED ABOVE SFC. IT IS UNCERTAIN TO WHAT
EXTENT...IF ANY...ALREADY MRGL SVR POTENTIAL FROM LATE IN DAY-2
PERIOD EXTENDS INTO EARLY DAY-3 ACROSS THIS REGION...GIVEN MULTITUDE
OF FACTORS CONTRIBUTING TO WEAK DEEP-TROPOSPHERIC LAPSE RATES DURING
THAT TIME FRAME. DURING DAYLIGHT HOURS...EXPECT PREFRONTAL BOUNDARY
LAYER TO DESTABILIZES SOMEWHAT FROM COMBINATION OF SLOW SFC HEATING
AND THETAE ADVECTION...WITH SERN FRINGES OF STG MID-UPPER FLOW
OVERHEAD. HOWEVER...WEAK LOW LEVEL SHEAR...WEAKENING CONVERGENCE
WITH TIME...AND LACK OF MORE ROBUST BUOYANCY ALL INDICATE SVR
POTENTIAL IS TOO ISOLATED/CONDITIONAL FOR AOA 5-PERCENT PROBABILITY
AREA ATTM.
..EDWARDS.. 11/14/2009
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z
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