Severe Thunderstorm Warning 11, NWS Brownsville, TX

DEEP SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1000 AM CDT SUN APR 20 2003

.SHORT TERM...ISOLATED SVR CELL LOCATED ABOUT 25 NM WEST OF LRD IS
MOVING ESE AT AROUND 30 KTS. THE LATEST MESOSCALE DISC FROM SPC IN
NORMAN INDICATES THAT THE CONV WILL CONTINUE TO FIRE PRIMARILY ON
THE MEXICAN SIDE OF THE RIVER WHERE HIGHER INSTABILITY WILL INTERACT
WITH THE APPROACHING COLD FRONT.  THE ADDITIONAL CONV FIRING TO THE
WEST OF THE CWA OVER NORTHERN MEXICO WILL POSSIBLY MOVE ACROSS THE
RIVER INTO THE WESTERN AND NORTHERNMOST PORTIONS OF THE CWA.
ACCORDINGLY...THE BEST CONV THIS MORNING WILL PERSIST OVER THE
WESTERN COUNTIES THIS MORNING AND WILL PLACE THE BEST CHANCES
HERE IN THE FIRST PERIOD OF THE ZFP.  THE NEXT QUESTION WILL BE IF
THE CONV WEST OF THE CWA CAN SURVIVE AS IT PUSHES EASTWARDS INTO THE
MORE STABLE AIRMASS NEAR THE COASTLINE.  WILL GO WITH A LITTLE LOWER
AFTERNOON POPS OVER THE EASTERN AND SOUTHERN PORTIONS OF THE CWA
MAINLY DUE TO THE ISOLD NATURE OF THIS SVR CELL WEST OF THE RIVER
AND THE ABOVE CONCERNS ABOUT LIMITED INSTABILTY.  HAVE MADE MINOR
CHANGES TO THE FIRST PERIOD OF THE ZFP...OTHERWISE OVERALL FORECAST
TREND LOOKS OK.

.MARINE...A MODERATE ONSHORE FLOW WILL CONTINUE ALONG THE LOWER TX
COASTLINE AHEAD OF THE APPROACHING SURFACE FRONT.  OFFSHORE SWELLS
ARE PRETTY HEALTHY WITH READINGS AT BUOY020 REACHING NEAR 5 FT. THE
OVERALL PGF WILL REMAIN WEAK ENOUGH NOT TO REQUIRE SCAS ATTM.
HOWEVER...WILL MAINTAIN A MENTION OF SCEC IN ALL MARINE ZONES.  WILL
MAKE MINOR ADJUSTMENTS TO THE CWF.

.AVIATION...LOW CIGS OVER THE VALLEY AIRPORTS WILL LIKELY IMPROVE
SLOWLY THIS AFTERNOON BUT WILL REMAIN AT OR BELOW VFR/MVFR LEVELS
THROUGHOUT THE DAY.  WILL MAINTAIN THE MENTION OF AFTERNOON AND
EVENING CONV AS THE SURFACE FRONT GRADUALLY PUSHES CLOSER TO THE
LOWER VALLEY PROVIDING A LITTLE MORE LIFT.

.BRO...NONE.

SYNOPTIC-AVIATION-MARINE...60/MESO...ABBOTT

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

TXZ248>257-210900-

HAZARDOUS WEATHER OUTLOOK...UPDATE
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1052 AM CDT SUN APR 20 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...TODAY AND TONIGHT.

ISOLATED INTENSE THUNDERSTORMS WILL CONTINUE TO FORM ON THE MEXICAN
SIDE OF THE RIO GRANDE RIVER WEST OF LAREDO THROUGHOUT THE MORNING
AND AFTERNOON HOURS. SOME OF THUNDERSTORMS MAY MOVE EAST ACROSS THE
RIO GRANDE RIVER CROSSING INTO ZAPATA...STARR...JIM HOGG AND BROOKS
COUNTIES. THESE STORMS MAY PRODUCE BRIEF DOWNPOURS...FREQUENT DEADLY
LIGHTNING...HAIL AND GUSTY WINDS. SOME OF THESE STORMS MAY MOVE
SOUTH AND EAST THROUGHOUT THE AFTERNOON HOURS POSSIBLY AFFECTING
HIDALGO...KENEDY...WILLACY AND CAMERON COUNTIES LATER THIS
AFTERNOON AND THIS EVENING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

SMALL CRAFT ADVISORIES ARE POSSIBLE WEDNESDAY AND THURSDAY...AS
DEEPENING SURFACE LOW PRESSURE IN WEST TEXAS PROMOTES STRONG
SOUTHEAST WINDS AND HIGH SEAS.

.SPOTTER INFORMATION STATEMENT.

SPOTTER ACTIVATION MAY BE NECESSARY LATER TODAY AND TONIGHT.

SPEECE