Severe Thunderstorm Warning 44, NWS Brownsville, TX

DEEP SOUTH TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
240 PM CDT MON JUL 28 2003

CLOUDINESS DECREASED ACROSS THE COUNTY WARNING AREA EARLIER IN THE
AFTERNOON...AND NOW ENOUGH SUNSHINE HAS FILTERED THROUGH THE CLOUDS
TO FIRE UP ISOLATED THUNDERSHOWERS OVER THE COASTAL AND CENTRAL
SECTIONS.  AS THE AFTERNOON PROGRESSES...MORE WIDESPREAD DEEP
CONVECTION IS EXPECTED INLAND AS A MASS OF MOISTURE IS MOVING
NORTHWEST INTO THE COUNTY WARNING AREA.  THIS MOISTURE...IN THE FORM
OF SHOWERS AND THUNDERSTORMS...EXTENDS SOUTHEAST FOR OVER 200 MILES
INTO THE GULF.  WITH THE COMBINATION OF MILD INSTABILITY AND
ABUNDANT MOISTURE...A CHANCE OF SHOWERS AND THUNDERSTORMS ARE
POSSIBLE IN THE NEAR TERM.

PREVIOUS THINKING HAS NOT CHANGED MUCH...SEE MORNING DISCUSSION FOR
SLIGHTLY MORE IN-DEPTH MODEL DISCUSSION.  THE UPPER LEVEL LOW
PRESSURE TROUGH OVER FAR WEST TEXAS THAT IS PROVIDING A MEASURE MORE
INSTABILITY THAN NORMAL SHOULD SLIDE WEST DURING THE NEXT DAY OR
TWO.  MEANWHILE...A FRONTAL BOUNDARY WILL PUSH INTO CENTRAL TEXAS.
WILL KEEP ISOLATED SHOWERS/TSTRMS IN THE FORECAST THROUGH THURSDAY
DUE TO THE FRONTAL PRESENCE AND LACK OF REGIME CHANGE.

MARINE...AT 1 PM BOY020 REPORTED SE WINDS NEAR 5 KT WITH SEAS 2 FT
AT 5 SEC.  MSAS SFC ANALYSIS SHOWS LGT/MDT ONSHORE FLOW...AS RIDGE
ALONG LA COAST HAS SPREAD SW OVR DPSOTEX COASTAL WATERS. 12Z MESOETA
RUN PROGS THIS RIDGE TO SLIDE EAST...RESULTING IN A RETURN OF MDT SE
WINDS OVR MARINE ZONES THIS EVENING. THIS FLOW WILL ALTERNATE BTWN
LGT AND MDT FOR THE REMAINDER OF THE WEEK UNDER THE INFLUENCE OF THE
WESTERN EXTENSION OF THE AZORES HIGH. H7 LEVEL BEGINS DRYING SOME
TONIGHT...FOLLOWED BY MID/UPR LEVELS ON TUE...AS W CONUS H5 RIDGE
CENTERED OVR THE GREAT BASIN TDA MOVES OVR NM/W TX BY SAT.
SUFFICIENT LOW LEVEL MOISTURE SHUD REMAIN IN PLACE FOR ISOLD
CONVECTION THRU THE FCST PD.

AVIATION...GENERALLY VFR CONDITIONS THIS AFTN AND TONIGHT...EXCEPT
FOR BRIEF PD OF VIS AND CIGS REDUCTIONS AND INCREASED WINDS DURING
THE AFTERNOON AND EARLY EVE SHRA/TSRA. UPR LEVELS OF ATMOS BEGIN
DRYING TONIGHT...A CHANGE TO MORE SEASONAL WEATHER FOR THE REMAINDER
OF THE WEEK.

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE        EB 079/095 079/093 077 20/20/20/20/10
HARLINGEN          EB 076/096 076/096 075 20/20/20/20/10
MCALLEN            EB 076/096 076/095 075 20/20/20/20/10
RIO GRANDE CITY    EB 075/098 075/098 074 20/20/20/20/10
SOUTH PADRE ISLAND EB 079/090 080/091 080 20/20/20/20/10

.BRO...WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPTIC...69
AVIATION/MARINE...59
MESO...ABBOTT

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

TXZ248>257-291100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
600 AM CDT MON JUL 28 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
EASTERN PORTIONS OF DEEP SOUTH TEXAS THIS AFTERNOON AS A SEABREEZE
FRONT MOVES INLAND INTERACTING WITH AN UPPER LEVEL LOW OVER WEST
TEXAS. BRIEF HEAVY RAINFALL AS WELL AS BRIEF GUSTY WINDS CAN BE
EXPECTED WITH THUNDERSTORMS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

EXPECT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP
ALONG THE SEABREEZE FRONT IN THE AFTERNOON HOURS.

.SPOTTER INFORMATION STATEMENT.

SPOTTER ACTIVATION IS NOT EXPECTED.

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