[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 140101
SWODY1
SPC AC 140100

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0800 PM CDT SAT MAY 13 2006

VALID 140100Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF NERN TX INTO
EXTREME SERN OK...THE LOWER MS VALLEY AND PARTS OF THE SERN
STATES...

...SRN PORTIONS OF TN VALLEY THROUGH PORTIONS OF THE SERN STATES...

ZONE OF LARGE SCALE ASCENT ASSOCIATED WITH EXIT REGION OF A SEWD
MOVING JET STREAK IS CONTRIBUTING TO THE DEVELOPMENT OF SCATTERED
THUNDERSTORMS FROM CNTRL AND NRN AL THROUGH PART OF NRN GA AND SRN
TN. INSTABILITY IS SOMEWHAT LIMITED WITH BOUNDARY LAYER DEWPOINTS
GENERALLY IN THE 50S...BUT STEEP LAPSE RATES AND BOUNDARY LAYER
WARMING HAVE RESULTED IN MLCAPE ON THE ORDER OF 500 TO 1000 J/KG.
STRONG DEEP LAYER SHEAR OF 50+ KT ENHANCED BY THE UPPER JET AND
CHARACTERIZED BY SSWLY LOW LEVEL FLOW VEERING TO NWLY AT 6 KM IS
RESULTING IN A FAVORABLE KINEMATIC ENVIRONMENT FOR STORMS TO ROTATE.
STEEP MID LEVEL LAPSE RATES AND COOL THERMODYNAMIC PROFILES AS WELL
AS POTENTIAL FOR MID LEVEL UPDRAFT ROTATION ARE CONTRIBUTING TO A
THREAT FOR LARGE HAIL WITHIN THE STRONGER STORMS. ISOLATED DAMAGING
WIND IS ALSO POSSIBLE GIVEN THE RELATIVELY DRY BOUNDARY LAYERS.
SEVERE THREAT IS EXPECTED TO PERSIST AT LEAST INTO THE MID EVENING
AS THE ATMOSPHERE DESTABILIZES EWD INTO GA AND WRN PARTS OF THE
CAROLINAS.


...NERN TX...EXTREME SERN OK THROUGH THE LOWER MS VALLEY...

A SURFACE FRONT EXTENDS FROM CNTRL AR WWD INTO SRN OK. THIS BOUNDARY
WILL LIKELY SHIFT SWD INTO NRN TX AND SRN AR OVERNIGHT AS AN UPPER
LEVEL JET SHIFTS SEWD THROUGH THE TN VALLEY. THE ATMOSPHERE S OF
THIS BOUNDARY HAS BECOME QUITE UNSTABLE WITH STEEP MID LEVEL LAPSE
RATES AND COOL MID LEVEL TEMPERATURES ABOVE BOUNDARY LAYER DEWPOINTS
IN THE 60S. THE 00Z FORT WORTH RAOB SHOWS 3000 J/KG OF MLCAPE AND
8.9 C/KM LAPSE RATES BETWEEN 700 AND 500 MB. HOWEVER...IT ALSO SHOWS
A RATHER PRONOUNCED CAP. A SLY LOW LEVEL JET WILL INCREASE TONIGHT
ACROSS TX AND IMPINGE ON THE SWD MOVING BOUNDARY. LIFT ASSOCIATED
WITH WARM ADVECTION AND INCREASING FRONTOGENETIC FORCING IN THE
VICINITY OF THE BOUNDARY SHOULD EVENTUALLY WEAKEN THE CAP AND
CONTRIBUTE TO THUNDERSTORM INITIATION LATER THIS EVENING FROM NERN
TX INTO THE LOWER MS VALLEY. GIVEN THE VERY STEEP MID LEVEL LAPSE
RATES AND SUPERCELL WIND PROFILES...VERY LARGE HAIL COULD ACCOMPANY
THE STRONGER STORMS. ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE.

..DIAL.. 05/14/2006