Severe Thunderstorm Warning 178, NWS Houston/Galveston, TX

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
945 AM CDT MON AUG 11 2003

FORECAST CHALLENGE FOR TODAY INCLUDES COVERAGE AND STRENGTH OF
THUNDERSTORMS.  12Z SOUNDING PARAMETERS FROM CRP AND LCH BOTH INDICATE
CAPES NEAR 4300 AND THE LI NEAR -8.  THE UPPER HIGH WAS LOCATED NEAR
THE FOUR CORNERS REGION AND THE EASTERN HALF OF TX WAS UNDER DIFFLUENT
FLOW AT 200 AND 300 MB.  THE 500 MB LEVEL SHOWED A STRONG SHORTWAVE
TROUGH PUSHING INTO SE TX FROM THE NORTH.  THE DIFFLUENT FLOW WAS
FORECAST BY THE MODELS TO MOVE OVERHEAD OF THE FORECAST AREA AND
SOUTH-SOUTHWEST THROUGHOUT THE DAY.

THE CURRENT POPS LOOK GOOD FOR MOST AREAS...THOUGH THE SOUTHWEST WAS A
BIT LOW CONSIDERING THE CURRENT SITUATION AND REASONABLE MODEL
FORECAST.  WILL UP THE FAR SOUTHWEST FROM 30 TO 50 PERCENT TO ACCOUNT
FOR THE EXPECTED COVERAGE.  THE SEVERE POTENTIAL SHOULD START BEING
REALIZED OVER THE NORTHEASTERN COUNTIES IN THE NEXT COUPLE OF HOURS
AND THEN SPREAD OVER THE REMAINDER OF SE TX THROUGH THE EARLY AND MID
AFTERNOON.  THE ONLY OTHER ITEM TO CONSIDER ARE FORECAST HIGH
TEMPERATURES.  IF THE STORMS REALLY GET WIDESPREAD AND WORK OVER THE
ATMOSPHERE...TEMPERATURES MAY NOT GET AS HIGH AS EXPECTED OVER SOME
AREAS.  HOWEVER...UPPER 80S TO LOWER 90S STILL POSSIBLE AND WILL NOT
CHANGE THESE AT THE PRESENT TIME.

MAIN ISSUE FOR THE AVIATION SITES WILL BE THE TIMING AND STRENGTH OF
THUNDERSTORMS.

PL-40
33

.HGX...NONE.

GMZ330-335-TXZ163-164-176>179-195>200-210>214-226-227-235>238-121200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
700 AM CDT MON AUG 11 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST TEXAS.

...SLIGHT CHANCE OF SEVERE THUNDERSTORMS TODAY...

.DAY ONE...TODAY AND TONIGHT.
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS SHOULD DEVELOP IN
NORTH AND NORTHEAST TEXAS THIS MORNING AND MOVE INTO SOUTHEAST TEXAS
TODAY. UPPER LEVEL WINDS WILL BECOME INCREASINGLY FAVORABLE FOR
SEVERE THUNDERSTORMS THROUGHOUT THE DAY. WIND DAMAGE WILL BE THE
PRIMARY SEVERE WEATHER THREAT...THOUGH HAIL WILL ALSO BE POSSIBLE.
LOCALIZED 2 INCH RAINFALL AMOUNTS MAY FALL IN THE STRONGER STORMS.

LARGELY DEPENDING ON AREAL THUNDERSTORM COVERAGE THIS AFTERNOON...
THERE IS ALSO A SMALL POSSIBILITY THAT ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP THIS EVENING NEAR THE COLLEGE STATION AREA AND MOVE
SOUTHWARD OVERNIGHT. CHANCES OF THIS HAPPENING WILL BE LOWER IF
THERE IS QUITE A BIT OF PRECIPITATION IN THAT AREA DURING THE
AFTERNOON HOURS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. FAIRLY GOOD
CHANCES OF RAINFALL ARE IN THE FORECAST TUESDAY AND WEDNESDAY AS AN
UPPER LEVEL LOW MOVING INTO THE REGION INTERACTS WITH ABUNDANT
MOISTURE ALREADY IN PLACE. ON TUESDAY...THE BETTER CHANCES OF
SHOWERS AND THUNDERSTORMS SHOULD BE ACROSS THE SOUTHERN HALF OF
SOUTHEAST TEXAS...ESPECIALLY ALONG THE COAST. RAINFALL COULD BECOME
WIDESPREAD ON WEDNESDAY AS A COASTAL TROUGH MOVES INLAND. PROLONGED
RAINFALL DURING THIS TIMEFRAME MAY ENHANCE THE FLASH FLOOD POTENTIAL.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED LATE THIS MORNING OR THIS
AFTERNOON.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
0110 PM CDT MON AUG 11 2003

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1130 AM    GROVETON                  TX   WIND DAMAGE
08/11/03   TRINITY                        TREES DOWN AT COURTHOUSE

1210 PM    POINT BLANK               TX   0.88 IN HAIL
08/11/03   SAN JACINTO

1220 PM    RIVERSIDE                 TX   WIND DAMAGE
08/11/03   WALKER                         TREES DOWN

LW