Damaging Winds in Texas, August 11, 2004

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
225 PM CDT WED AUG 11 2004

DISCUSSION...
COLD FRONT IS APPROACHING THE OUTFLOW BOUNDARY NW OF
THE AREA AND SCT STRONG/SVR TSTMS ARE THE RESULT. WE
EXPECT SHWRS AND TSTMS TO BECOME MORE NUMEROUS ALONG THE
BOUNDARY AS THE AFTERNOON PROGRESSES. WE ALSO EXPECT SCT
SHWRS AND TSTMS TO CONTINUE TO DEVELOP ALONG THE SEA
BREEZE.

MAIN ISSUE IS PRECIP COVERAGE AND SVR TSTM POTENTIAL THIS
EVENING ACROSS SE TX. BEST CHC APPEARS TO BE ACROSS
THE NW ZONES AS THE BOUNDARY WILL BE IN THIS ZONE LATE
THIS AFT/EARLY EVE WITH HEATING STILL OCCURRING. PRECIP
COVERAGE BECOMES MORE QUESTIONABLE FURTHER SOUTH AS
BOUNDARY MOVES THROUGH LATER IN THE EVENING. HOWEVER...BASED
ON THE SOUTHEAST FLOW THAT IS DEVELOPING AHEAD OF THE
BOUNDARY OVER SE TX...THINK THAT THE LOW-LEVEL CONVERGENCE
WILL BE SUFFICIENT FOR CONTINUED TSTM DEVELOPMENT. WILL
RAISE POPS TO LIKELY AREAWIDE TONIGHT. WILL MAINTAIN SVR
TSTM POSSIBILITY...WITH THE MAIN THREATS DAMAGING WINDS
AND LARGE HAIL.

WILL DROP POPS TOMORROW WITH VERY DRY AIR PUSHING IN
BEHIND THE FRONT. THIS UNSEASONABLY COOL AIRMASS WILL BE
QUITE A CHANGE FOR THIS TIME OF YEAR. IN FACT...AM
FORECASTING AT OR BELOW RECORD LOWS FOR INLAND LOCATIONS
ON SAT MORNING.

FOR THE MARINE AREA...WE EXPECT WINDS TO INCREASE TO CAUTION
LEVELS ON THU BEHIND THE FRONT DUE TO THE RELATIVELY COOL AIR
OVER WARM WATER AND THE TIGHTENING PRESSURE GRADIENT.
&&

.HGX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 88 63 88 61/ 70 00 00 00
HOUSTON(IAH)          70 89 64 88 63/ 60 05 00 00
GALVESTON (GLS)       76 87 72 86 72/ 60 10 00 00
&&

33/43

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1047 AM CDT WED AUG 11 2004

TXZ163-164-176>179-195>200-210>214-226-227-235>238-121200-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-GALVESTON-
GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-MONTGOMERY-
POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-WHARTON-
1047 AM CDT WED AUG 11 2004

...SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHWEST AREAS THIS
AFTERNOON AND ACROSS ALL OF SOUTHEAST TEXAS THIS EVENING...

.DAY ONE...TODAY AND TONIGHT.
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A COOL FRONT
NORTHWEST OF SOUTHEAST THIS AFTERNOON. AS THE FRONT MOVES
SOUTHEAST...THUNDERSTORMS ARE EXPECTED TO MOVE INTO NORTHWEST PORTIONS
OF THE AREA. BECAUSE THERE IS A LAYER OF DRY AIR ABOVE A LOW-
LEVEL MOIST LAYER IN THE ATMOSPHERE...STRONG AND DAMAGING WINDS WILL
BE A POSSIBILITY WITH ANY STRONG THUNDERSTORMS THAT DEVELOP. AS THE
FRONT MOVES SOUTH THIS EVENING...THE SEVERE THUNDERSTORM THREAT WILL
ALSO SHIFT SOUTH...AND THEREFORE INCLUDE ALL OF SOUTHEAST TEXAS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.
NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED LATE THIS AFTERNOON MAINLY FOR THE
AREA ALONG AND NORTH OF A BRENHAM...HUNTSVILLE...GROVETON LINE.
SPOTTER ACTIVATION MAY BE NEEDED ACROSS ALL OF SOUTHEAST TEXAS
TONIGHT.