Severe Thunderstorm Warning 177, NWS Austin/San Antonio, TX

SOUTH CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
210 PM CDT THU SEP 11 2003

SAT PIXS THIS AFTN SHOW STG S/W ENERGY ROTATING AROUND THE BASE OF
THE UPR TROF IN THE FORM OF DEVELOPING CONVECTION OVER WEST TX.
THIS S/W ENERGY WHICH IS EXPECTED TO GENERATE A SQUALL LINE...WOULD
FAVOR THE GFS SOLN OF A FASTER/STRONGER UPR TROF THAN INDICATED BY
THE LATEST ETA.  AM THEREFORE LEANING TOWARD THE GFS SOLN WHICH IS
ALSO MORE IN LINE WITH THE UKMET/ECMWF(SEE HPC MODEL DISC).  THE GFS
QPF AMOUNTS ARE QUITE IMPRESSIVE OVER THE EWX CWA AND PREFER A BLEND
OF THE GFS AREA WITH ETA AMOUNTS WHICH MATCHES THE WGRFC QPF.  THE
EASTWARD MOVG SQUALL LINE WILL INTERACT WITH INCREASING SLY INFLO OF
GULF MOISTURE AND PWS AOA 2 INCHES.  STG SFC CONVERGENCE NEAR THE
SFC TROF/FRONT ALONG WITH UPR DIFFLUENCE AHEAD OF THE UPR TROF WILL
CREATE A FAVORABLE ENVIRONMENT FOR NORTHEASTWARD TRAINING CELLS.
WILL ALSO CONT TO MENTION OF SVR THIS EVENING FOR THE NWRN CWA AS
MENTION IN AN EARLIER AFD.

THEREFORE NEED TO EXPAND THE FFA TO INCLUDE MUCH OF THE HILL COUNTRY
THRU FRIDAY...ALTHOUGH EXPECT HEAVIEST RAINS TO HAVE MOVED EAST OUT
OF THE HILL COUNTRY BY FRI AFTN...WITH HEAVY RAIN POTENTIAL CONTG IN
THE EAST. SHOULD SEE RAPID CLEARING IN THE WRN CWA BY FRI AFTN AND
IN THE EAST FRI EVENING.  PLEASANT-QUIET...COOLER/DRIER WEEKEND IN
STORE FOR S TX AS THE SFC RDG PREVAILS.

GENERALLY DRY WESTERLY UPR FLOW TO PREVAIL OVER THE WEEKEND INTO
EARLY NEXT WEEK WITH A SHALLOW RETURN FLOW RESUMING BY MID WEEK AS
THE NEXT UPR TROF DIGS INTO THE GREAT BASIN.

AUS TB 067/081 064/088 064 883
    BBBBB 086/060 086/060 087/063 090/061 090 00000000000
DRT BU 068/087 062/089 062 841
    BBBBB 089/064 089/067 090/067 094/068 094 00000000000
SAT TB 069/083 063/088 063 883
    BBBBB 087/063 089/065 089/068 092/066 092 00000000000

.EWX...FLASH FLOOD WATCH TONIGHT AND FRIDAY FOR THE HILL COUNTRY
       AND MUCH OF SOUTH CENTRAL TEXAS.

TXZ171>173-183>194-202>209-217>225-228-121100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
600 AM CDT THU SEP 11 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...TODAY
AN APPROACHING UPPER LEVEL TROUGH AND COLD FRONT WILL INTERACT WITH A
MOIST AIRMASS TO PRODUCE SHOWERS AND THUNDERSTORMS.  SCATTERED RAINS
WILL DEVELOP TODAY...THEN BECOME NUMEROUS TO WIDESPREAD LATER THIS
AFTERNOON INTO TONIGHT.  HEAVY RAINFALL IS LIKELY BEGINNING LATER
THIS AFTERNOON THEN CONTINUING THROUGH TONIGHT.  THESE RAINS WILL
LIKELY CAUSE FLOODING PROBLEMS WITH THE GREATEST THREAT ALONG AND
EAST OF A BURNET TO SAN ANTONIO TO JOURDANTON LINE WHERE A FLASH
FLOOD WATCH HAS BEEN ISSUED.  DANGEROUS LIGHTNING AND GUSTY WINDS
CAN ALSO BE EXPECTED...WHILE HAIL MAY APPROACH SEVERE LEVELS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
NUMEROUS TO WIDESPREAD SHOWERS AND THUNDERSTORMS WILL BE ONGOING
FRIDAY AS AN UPPER LEVEL TROUGH AND COLD FRONT MOVE ACROSS THE
AREA.  HEAVY RAINFALL IS LIKELY INTO MUCH OF FRIDAY.  THROUGH
FRIDAY...RAINFALL AMOUNTS WILL AVERAGE 1 TO 3 INCHES WITH ISOLATED
TOTALS OF 3 TO 5 INCHES OR HIGHER POSSIBLE.  FLOODING PROBLEMS WILL
LIKELY BE ONGOING WITH THE GREATEST THREAT ALONG AND EAST OF A BURNET
TO SAN ANTONIO TO JOURDANTON LINE WHERE A FLASH FLOOD WATCH HAS BEEN
ISSUED.  DANGEROUS LIGHTNING AND GUSTY WINDS CAN ALSO BE EXPECTED...
WHILE HAIL MAY APPROACH SEVERE LEVELS.  THE RAINS WILL END FROM THE
WEST FRIDAY NIGHT INTO EARLY SATURDAY.

.SPOTTER INFORMATION STATEMENT...
SOME SPOTTER ACTIVATION MAY BE REQUIRED TODAY THROUGH FRIDAY.