Severe Thunderstorm Warning 19, NWS Brownsville, TX

DEEP SOUTH TEXAS FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE BROWNSVILLE TX
500 PM CDT FRI APR 25 2003

***SHORT TERM UPDATE...AFTERNOON DIRUNAL HEATING IS APPARENTLY
STRONG ENOUGH TO FIRE OFF SOME CONV OVER THE NORTHERN AND WESTERN
PORTIONS OF THE CWA.  ADDITIONAL LIFT OCCURING ALONG AND AHEAD OF
THE WESTWARD MOVING AFTERNOON SEA-BREEZE IS ALSO HELPING ENHANCE
CONV.  WILL UPDATE TO INCLUDE A MENTION OF EARLY EVENING CONV OVER
THE NORTHERN AND WESTERN TIER OF COUNTIES IN THE BRO CWA.  THE LOSS
OF THE AFTERNOON HEATING AFTER SUNSET SHOULD ALLOW CONV TO DIE OFF
LATER THIS EVENING.  OTHERWISE...THE REST OF THE ZFP LOOKS OK.***

TONIGHT THRU MON...THICKEST SMOKE FROM FIRES OVER CHIAPAS/N
GUATEMALA REGION IS BEING ADVECTED NNE ACRS THE CNTRL GULF BY LOW
LEVEL WINDS. CLOSER TO HOME...H8 SHEAR ZONE ACRS DPSOTEX INTO NE MEX
COASTAL WATERS IS ADVECTING SOME SMOKE FROM THE W BAY OF CAMPECHE N
ALONG THE SIERRA MADRE ORIENTAL. AGGRAVATING MATTERS IS THE LOW
LEVEL INVERSION WHICH DROPPED FROM 2500 FT YDA TO 1100 FT THIS
MORNING. SOME BRIEF RELIEF WILL BE OFFERED THIS AFTN...AS TAIL END
OF COOL FRONT WAGGLES INTO THE CWA...FORCING THE SHEAR ZONE S ALONG
THE RIO GRANDE AND BREAKING THE INVERSION THEREBY ALLOWING SMOKE TO
MIX OUT SOME. LOW LVL EASTERLY FLOW OVER W GULF WILL POOL MOISTURE
ALONG THE SIERRA MADRE ORIENTAL...UNDER H8 CAP SO EXPECT SOME LOW
CLDS TO RETURN TONIGHT...BUT SHUD MIX OUT BY AFTN. WITH HIGH DEWPTS
AND LIGHT WINDS...WILL MENTION FOG TONIGHT. SUN SHUD SEE A RE-RUN
WITH NIGHTTIME/EARLY MORNING LOW CLD COVER SAT NIGHT...AS DEEP SE
FLOW ADVECTS WARM MOIST GULF AIR. CLOUDS WILL MIX OUT AS INVERSION
BREAKS...LEADING TO MOSTLY SUNNY SUN AFTN. E-SE LOW LEVEL FLOW OVER
WEEKEND SHOULD TEMPER AFTN TEMPS. DEEP WAA CONTINUES SUN NIGHT...AS
MOISTURE FLOWS TWD SFC BNDRY OVR CNTRL PLAINS. RIPPLES IN NW FLOW UP
THE H5 RIDGE OVR THE NW GULF INTO THE NRN HI PLAINS WILL PROVIDE UVM
AND SLGT CHC OF TSRA/SHRA FOR MON.

TUE THRU FRI...RIPPLES MOVE THRU THE H5 RIDGE ACRS THE PLAINS IN SW
FLOW DOWNSTREAM OF CUTOFF LOW OFF W COAST. LEE-SIDE TROUGH ACRS N
NUEVO LEON AND TAMPICO GENERATES SOME UVM ON TUE SUFFICIENT FOR
ISOLD TSRA/SHRA ON TUE AND ENTRAINS DRIER AIR INTO DPSOTEX FOR
WED...SO WILL REMOVE MENTION OF TSRA/SHRA FOR WED/THU...GO WITH
PTCLDY WED-FRI AND BUMP UP AFTN TEMPS A BIT FOR WED AND THU. BREEZY
E ON WED-FRI WITH TIGHTER SPG DUE TO SFC TROUGH FROM NE MEX INTO
CNTRL PLAINS. LLJ INCRS FRI NIGHT...AHD OF H5 CLOSED LOW DROPPING SE
ACRS CA...INCRG CLD COVER.

MARINE...MARINE...LIGHT WESTERLY WINDS AND 4 FEET SEAS NOW REPORTED
AT BUOY 020. A HIGH PRESSURE SYSTEM MOVING INTO THE AREA WILL VEER
WINDS TO THE EAST THIS WEEKEND.  MONDAY AND TUESDAY SOUTHEASTERLY
WINDS WILL RETURN IN RESPONSE TO A TROUGH APPROACHING WEST TEXAS.
THE SOUTHEASTERLY WINDS AND AN ACTIVE SUBTROPICAL JET WILL INCREASE
THE POSSIBILITY OF ISOLATED SHOWERS ON MONDAY AND TUESDAY.

AVIATION...CLEAR SKIES AND LIGHT VARIABLE WINDS AT BRO. TONIGHT
LIGHT WINDS AND HIGH RELATIVE HUMIDITIES ARE EXPECTED WHICH WILL
RESULT IN FOG.

.BRO...NONE.

PRELIMINARY NUMBERS FOR COORDINATION PURPOSES ONLY...
BRO BB 069/084 068/084 068 00/00/00/00/00
HRL BB 067/086 067/086 067 00/00/00/00/00
MFE BB 068/087 065/087 065 00/00/00/00/00
RGC BB 066/088 064/088 064 00/00/00/00/00
SPI BB 069/080 069/080 070 00/00/00/00/00

SYNOPTIC...59
MESO-AVIATION-MARINE...60

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

TXZ248>257-260900-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
510 PM CDT FRI APR 25 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...THIS EVENING AND TONIGHT.

A WESTWARD MOVING SEA BREEZE HAS COMBINED WITH ABUNDANT AFTERNOON
HEATING TO FIRE OFF SOME SCATTERED EARLY EVENING SHOWER AND
THUNDERSTORM ACTIVITY.  THESE SHOWERS AND THUNDERSTORMS WILL
PERSIST THROUGHOUT SUNSET AND THEN WILL DISSIPATE AFTER SUNSET.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SMALL CRAFT ADVISORIES ARE POSSIBLE BEGINNING SUNDAY...AS DEEPENING
LOW PRESSURE OVER WEST TEXAS PRODUCES MODERATE TO STRONG ONSHORE
WINDS AND BUILDING SEAS.

.SPOTTER INFORMATION STATEMENT.

SPOTTER ACTIVATION MAY BE REQUIRED THROUGHOUT SUNSET TONIGHT.

SPEECE