[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 131947
SWODY1
SPC AC 131944

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0144 PM CST SAT JAN 13 2007

VALID 132000Z - 141200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
UPPER TROUGH WILL CONTINUE SHIFTING EWD ACROSS THE ROCKIES THIS
PERIOD...WITH EMBEDDED UPPER LOW TO REACH THE FOUR CORNERS REGION BY
THE END OF THE PERIOD.  AT THE SURFACE...COLD FRONT WILL CONTINUE
MOVING SWD ACROSS SRN AND ERN TX...WITH SUBTLE LOW LIKELY TO PERSIST
INVOF SRN AR ALONG FRONT THROUGH THE PERIOD.

...MIDDLE RIO GRANDE VALLEY/PARTS OF S TX NEWD INTO NRN LA/SRN AR...

SHOWERS AND SCATTERED THUNDERSTORMS ARE ONGOING ATTM WITHIN
MARGINAL/ELEVATED INSTABILITY N OF SURFACE FRONT...WHICH NOW EXTENDS
FROM A WEAK LOW IN SWRN AR SSWWD ACROSS E TX...AND THEN WWD ACROSS
SRN PORTIONS OF THE HILL COUNTRY TO NEAR DRT.

AOB 1000 J/KG MEAN-LAYER CAPE IS INDICATED ACROSS DEEP S TX FROM
ROUGHLY SAT SWD...THOUGH AIRMASS REMAINS CAPPED ATTM.  THIS CAPPING
SHOULD CONTINUE TO GENERALLY INHIBIT CONVECTIVE DEVELOPMENT S OF
FRONT THROUGH THE PERIOD.

GREATEST POTENTIAL FOR THUNDERSTORMS REMAINS N OF FRONT...WHERE WARM
ADVECTION/ISENTROPIC LIFT PROVIDES SUFFICIENT LOW-LEVEL ASCENT FOR
STORM INITIATION.  HOWEVER...MUCH WEAKER INSTABILITY N OF BOUNDARY
SUGGESTS ONLY A LIMITED HAIL THREAT -- MAINLY FROM THE RIO GRANDE
VALLEY EWD ACROSS THE HILL COUNTRY.  ANY STORMS WHICH COULD DEVELOP
NEAR OR JUST S OF FRONT WOULD QUICKLY BE CARRIED NNEWD ACROSS THE
BOUNDARY ACROSS THIS REGION...SO SURFACE-BASED SEVERE THREAT SHOULD
REMAIN QUITE LOW.

FURTHER NE...FRONT IS ORIENTED SSW-NNE ACROSS E TX.  IN THIS
REGION...MUCH MORE LIMITED INSTABILITY AND LOW-LEVEL CAP IS
HINDERING THE POTENTIAL FOR ORGANIZED STORMS...DESPITE FAVORABLE
DEEP-LAYER SHEAR.  HOWEVER...WILL MAINTAIN LOW-PROBABILITY THREAT
FOR AN ISOLATED WIND GUST OR WEAK/BRIEF TORNADO...AS CELL MOTION
WOULD MORE CLOSELY PARALLEL THE FRONT AND PERHAPS ALLOW A STORM TO
REMAIN SURFACE-BASED AS IT SHIFTS NNEWD.

..GOSS.. 01/13/2007