Severe Thunderstorm Warning 31, NWS Brownsville, TX

DEEP SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
150 PM CDT TUE JUN 3 2003

88D LOOP SHOWS A FEW MARINE SHRA LURKING AROUND 60 NM SE OF BRO...
NEAR THE EDGE OF 2.00+ PWAT AIR APPEARING IN GOES SOUNDER IMAGERY.
BELIEVE MODEL SOLUTIONS FOR THIS AREA REMAIN EXTREMELY SENSITIVE TO
INITIAL CONDITIONS...AS CWA REMAINS VERY CLOSE TO H5 RIDGE AXIS
SEPARATING ERN US TROF FROM EPAC CLOSED LOW. GFS AND AVN CONTINUE TO
REMAIN EQUALLY INSISTENT ON DIAMETRICALLY OPPOSED SOLUTIONS
BEGINNING TOMORROW PM...WITH NO CONVERGENCE IN H5 SOLUTIONS NOTED
THU AND BEYOND. SPECIFICALLY...WILL ADHERE TO SLIGHT CHANCE POPS
TONIGHT FOR WESTERN COUNTIES WITH H5 VORT DROPPING SEWD THRU CENTRAL
TX AT PRESENT. UKMET AND ECMWF SUPPORT THE GFS SOLUTION...WHILE GFS
MOS HAS CONVERGED WITH THE ETA MOS POPS ON THU. WITH LOW CONFIDENCE
IN MODEL SOLUTIONS DEPENDENT UPON H5 HEIGHTS OVER MX...WILL GO WITH
MOS GUIDANCE CONSENSUS THRU THU NITE.

LONG TERM...ETA STILL HOLDS ON TO NW H5 FLOW SOLUTION FRI AM...SO
WILL LOWER GFS POPS FOR FRI. AFTER FRI...NCEP ENSEMBLES SUPPORT
BREAKDOWN OF H5 RIDGE SHIELDING THE CWA. WILL WALK FORECAST NUMBERS
TOWARD GFS SOLUTION DURING THE SAT THRU TUE TIME FRAME. FOR FRI
NITE...GFS PUSHES BNDRY BEHIND MCS THRU THE CWA...ASSOC WITH TWO
CONVECTIVE FEEDBACK BULLSEYES. WILL DISCOUNT THIS AND MAINTAIN SE
WINDS AND SLIGHT CHANCE POPS. FOR SAT THRU MON...WILL MAINTAIN LOW
END CHANCE POPS FOR SEA BREEZE CONVECTION. WILL DISCOUNT PROGGED
COLD FRONT INTO THE CWA BY GFS MON AS WELL. WILL GO WITH WEAKENING
SEA BREEZE TUE AS H5 RIDGE BUILDS IN FROM THE GULF.

MARINE...DAYTIME HEATING HAS NEGATED MIX DOWN OF WINDS OFF THE SFC
AGAIN TDY...WITH SE WINDS DECREASING FROM EARLY MORNING SPEEDS OF 20
TO 25 KTS...TO 10 TO 15 KTS NOW. SEAS AT 3 FEET OFFSHORE. LIGHT TO
MODERATE ONSHORE FLOW WILL TO PREVAIL THROUGH EARLY FRI AM...AS
RELATIVELY WEAK PRESSURE GRADIENT EXISTS OVER THE WESTERN GULF OF
MEXICO. H5 SHORTWAVE TROUGH EXPECTED TO MOVE THROUGH TX THURSDAY
PROVIDING ISOLATED CONVECTION FOR THE COASTAL WATERS. CONVECTION
EXPECTED TO INCREASE IN COVERAGE FRIDAY WITH ADDITIONAL SHORTWAVES
MOVING THROUGH THE COASTAL BEND. IN ADDITION...700MB LOW PROGGED TO
DEVELOP ACROSS THE LOWER TX COAST ENHANCING LAPSE RATES WITH LOW
LEVEL COOLING. WINDS EXPECTED TO INCREASE TO 25 KTS FRI...DECREASING
AND VEERING SOUTHWEST SAT...AS CF APPROACHES THE REGION.

AVIATION...MVFR CONDITIONS XPCTD TNGT...WITH CEILINGS AT 1300 FT.
VFR CONDITIONS BY WED PM WITH CEILINGS ABOVE 3000 FT. MVFR
CONDITIONS LIKELY TONIGHT WITH CEILINGS AT 1500 FT. IFR MAY BE IN
EFFECT EARLY THU FOR CIGS BELOW 1K FT WITH TSTMS IN VICINITY.

PRELIMINARY NUMBERS FOR COORDINATION PURPOSES ONLY...
BRO BB 078/094 079/093 078 00/10/10/20/10
HRL BB 075/097 076/096 075 00/10/10/20/10
MFE BB 078/099 078/098 078 00/10/10/20/10
RGC BB 076/102 077/100 077 10/20/10/20/10
SPI BB 080/090 080/089 079 00/10/10/20/20

BRO...NONE.

59/62

THIS PRODUCT IS ALSO AVAILABLE ON OUR INTERNET WEB PAGE AT:
HTTP://WWW.SRH.NOAA.GOV/BRO

TXZ248>257-040500-

HAZARDOUS WEATHER OUTLOOK...UPDATE FOR WATCH INFORMATION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
500 PM CDT TUE JUN 3 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...REST OF TODAY AND TONIGHT.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 10 PM TONIGHT FOR
CAMERON...WILLACY...HIDALGO...KENEDY...STARR...BROOKS...JIM HOGG AND
ZAPATA COUNTIES. ISOLATED TO SCATTERED SEVERE THUNDERSTORMS WILL BE
POSSIBLE ACROSS DEEP SOUTH TEXAS THROUGH 10 PM TONIGHT AS A LARGE
AREA OF CONVECTION MOVES SOUTH ACROSS THE COASTAL BEND AREA FROM
THE TEXAS HILL COUNTRY. ANY THUNDERSTORMS THAT FORM OR MOVE INTO
DEEP SOUTH TEXAS TONIGHT MAY PRODUCE LARGE HAIL...FREQUENT LIGHTNING
AND DAMAGING THUNDERSTORM WINDS THROUGH 10 PM.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS MAY DEVELOP
WEDNESDAY AND THURSDAY AS AN AREA OF WEAKNESS DEVELOPS IN THE UPPER
LEVEL RIDGE OVER DEEP SOUTH TEXAS. IN ADDITION...A WEAK COLD FRONT
IS EXPECTED TO MOVE INTO CENTRAL TEXAS FRIDAY PROVIDING A CHANCE OF
SHOWERS AND THUNDERSTORMS FOR THE WEEKEND.

.SPOTTER INFORMATION STATEMENT.

SPOTTER ACTIVATION WILL LIKELY BE REQUIRED LATER TONIGHT.

SPEECE

TXZ248>257-040500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
505 PM CDT TUE JUN 3 2003

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR ALL OF DEEP SOUTH
TEXAS THROUGH 10 PM TONIGHT...

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH
UNTIL 1000 PM CDT THIS EVENING FOR ALL OF DEEP SOUTH TEXAS. THIS
WATCH INCLUDES CAMERON...WILLACY...HIDALGO...KENEDY...STARR...
BROOKS...JIM HOGG AND ZAPATA COUNTIES. SOME CITIES AND TOWNS WITHIN
THE WATCH AREA ARE ZAPATA...HEBBRONVILLE...FALFURRIAS...SARITA...RIO
GRANDE CITY...MCALLEN...HARLINGEN...BROWNSVILLE...SOUTH PADRE ISLAND
AND RAYMONDVILLE.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE
FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN
THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND SHOULD LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS FROM THE NATIONAL WEATHER SERVICE OFFICE IN BROWNSVILLE.
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES.

LAW ENFORCEMENT AGENCIES...EMERGENCY MANAGEMENT OFFICIALS...STORM
SPOTTER GROUPS...AND OTHER INTERESTED CONCERNS SHOULD MONITOR THIS
SITUATION AND TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN
YOUR AREA.

STAY TUNED TO NOAA WEATHER RADIO FOR LATER STATEMENTS CONCERNING THIS
POTENTIALLY DANGEROUS SEVERE WEATHER THREAT.

FOR THE LATEST WEATHER FORECASTS AND WARNINGS FOR DEEP SOUTH TEXAS...
VISIT THE NATIONAL WEATHER SERVICE WEB SITE AT...

HTTP://WWW.SRH.NOAA.GOV/BRO

SPEECE