Severe Thunderstorm Warning 102, NWS Houston/Galveston, TX

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1013 AM CDT TUE AUG 27 2002

FORECAST PROBLEM OF THE DAY CONCERNS POPS AND SEVERE POSSIBILITIES.
MCS OVER N TX EVOLVED INTO A BOW ECHO AND THE ORIENTATION LOOKS TO
HAVE CHANGED OVER THE PAST HOUR TO MORE EAST-WEST.  UPDATED THE
FORECAST FOR HOUSTON AND TRINITY COUNTIES IN THE LAST HALF HOUR TO
REFLECT HIGHER POPS THERE.  FEEL THAT BASIC FORECAST ZONE GROUPING TO
BE GOOD AND ISSUED A HAZARDOUS WEATHER OUTLOOK TO CONCENTRATE ON THE
SEVERE IMPACT AND TO ALSO MENTION A SLIGHT RISK FOR HEAVY RAINFALL
IN THE EAST.

ON THE SYNOPTIC SCALE SE TX STILL UNDER THE INFLUENCE OF A NORTHWEST
FLOW AT 500 MB WITH THE HIGH OVER NORTHWESTERN MEXICO FROM 500 TO 200
MB.  AT 300 AND 200 MB GOOD DIFFLUENCE WAS NOTED TOWARD THE COAST OVER
SE TX...AND DEWPOINTS WERE AROUND 17 CELSIUS AT 850 MB AND 2 TO 4 AT
700 MB OVER SE TX.  ALSO...PW/S WERE BETWEEN 1.75 AND 2 INCHES AND
FEEL HEAVY RAINFALL WILL BE A SLIGHT THREAT...WILL DEAL WITH THAT
MAINLY IN THE HAZARDOUS WEATHER OUTLOOK AND NOT THE PUBLIC FORECAST.
THE SEVERE POSSIBILITIES LOOK GOOD...LI/S WERE -4 TO -9 AND CAPES 2100
TO 5800 AT LCH AND CRP RESPECTIVELY.  THE 700 TO 300 MB MEAN
STREAMLINES SHOW THAT THE FLOW IS FROM THE FTW AREA TO THE HOU AREA...
THEN SOUTHWEST TO NEAR THE BRO AREA.  AFTER THE CURRENT STORMS MOVE
THROUGH...WILL NEED TO KEEP AN EYE OUT FOR ANY THAT DEVELOP NORTH AND
EAST OF THE FORECAST AREA.

WILL WAIT TO UPDATE THE PUBLIC FORECAST TO AFTER 11 AM IF NEEDED.
FOR NOW THE FORECAST LOOKS ON TRACK.

PL-40
33

.HGX...NONE.

PREV PRELIMS...
CLL BB 096/073 096/073 096 332
IAH BB 095/074 095/073 093 442
GLS BB 091/081 090/080 089 442

TXZ163-164-176>179-195>200-210>214-226-227-235>238-280200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
945 AM CDT TUE AUG 27 2002

...A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY INTO THIS EVENING OVER
SOUTHEAST TEXAS...

A LARGE THUNDERSTORM COMPLEX OVER NORTHEAST TEXAS IS CURRENTLY MOVING
EAST-SOUTHEAST JUST NORTH OF SOUTHEAST TEXAS. THE SOUTHERN PORTION OF
THIS LINE WILL LIKELY AFFECT THE NORTHERN PORTIONS OF THE AREA THIS
MORNING. HOWEVER...AN OUTFLOW BOUNDARY FROM THESE THUNDERSTORMS WILL
MOVE SOUTH ACROSS SOUTHEAST TEXAS AND LIKELY INITIATE SCATTERED
THUNDERSTORMS LATER TODAY. THIS BOUNDARY COUPLED WITH HEATING WILL
CREATE AN ENVIRONMENT FAVORABLE FOR SEVERE THUNDERSTORM DEVELOPMENT.
THE PRIMARY SEVERE WEATHER THREATS WILL BE DAMAGING DOWNBURST WIND
GUSTS AND LARGE HAIL.

LOCALLY HEAVY RAINFALL WILL ALSO BE A POSSIBILITY ALONG AND NORTHEAST
OF A MADISONVILLE TO HOUSTON TO GALVESTON LINE DUE TO ABUNDANT
MOISTURE IN THE ATMOSPHERE. RAINFALL RATES OF 2 TO 3 INCHES AN HOUR
WILL BE POSSIBLE IN ANY STRONG THUNDERSTORMS THAT DEVELOP OVER
THE REGION TODAY AND INTO THIS EVENING.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL TELEVISION OR RADIO
STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS
CONCERNING THIS POTENTIAL SEVERE WEATHER THREAT.