Severe Thunderstorm Warning 39, NWS Brownsville, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
430 PM CDT FRI SEP 2 2005

.DISCUSSION...THE AFTERNOON CONVECTION HAS SHIFTED NORTH AND WEST OF
THE BRO AREA WHERE BETTER SUNSHINE HAS HELPED DESTABILIZE THE
AIRMASS ENOUGH TO ALLOW SOME ACTIVITY TO FIRE UP THIS EVENING. IN
ADDITION...MORE COVECTION IS FIRING UP TO THE SOUTHEAST OF THE BRO
AREA OVER THE GULF OF MEXICO. BELIEVE THAT THE PWAT VALUES OVER THE
REGION HAVE NOT CHANGED VERY MUCH FROM THAT INDICATED BY THE 12Z BRO
SOUNDING...SO THE TROPICAL AIRMASS REMAINS POOLED OVER THE REGION.
SOME SCATTERED CONVECTION MAY CONTINUE TO DEVELOP INLAND UNTIL THE
LOSS OF THE AFTERNOON HEATING...AFTERWHICH SOME MARINE CONVECTION
MAY CREEP INTO THE CWA FROM THE OFFSHORE WATERS LATER TONIGHT.  SO
WILL MAINTAIN CHANCE POPS FOR THE FIRST PERIOD. THE 500 MILLIBAR LOW
WHICH IS CENTERED OVER CENTRAL TEXAS IS PROGGED BY MODELS TO MEANDER
AROUND OVER THE NEXT COUPLE OF DAYS AFTERWHICH THE FEATURE WASHES
OUT AND 500 MILLIBAR RIDGING BUILDS INTO THE AREA FROM THE EAST AS
TROFFING DIGS DOWN ALONG THE EAST AND WEST COASTS OF THE U.S.  THIS
ALLOWS THE TROPICAL MOISTURE TO DRY OUT SOMEWHAT ON LABOR DAY AND
HAVE ACCORDINGLY MAINTAINED THE REDUCTION IN POPS TO MAINLY
DIURNALLY DRIVEN SEA BREEZE ACTIVITY DURING THE LATER HALF OF THE
NEXT WEEK. BELIEVE THAT MAV FORECAST HIGH TEMPERATURES MAY BE A BIT
HIGH IN THE SHORT TERM AND ARE NOT ACCOUNTING THE CLOUD COVER AND
RAIN EFFECTS ON AFTERNOON HIGHS.  SO HAVE UNDERCUT MAV HIGH TEMPS A
BIT. IN THE LONGER TERM...GFS/ECMWF INDICATE THAT THE 500 MILLIBAR
RIDGING PATTERN GETS SQUASHED DOWN A BIT AS TROFFING DIGS ACROSS THE
NORTHERN TIER OF THE CONUS AREA AND A 500 CLOSED LOW FORMS OVER THE
NORTHERN GULF OF MEXICO TOWARDS THE END OF NEXT WEEK.  THIS WILL
ALLOW TEMPS TO RETURN CLOSER TO CLIMO NEXT WEEK.
&&

.MARINE...BUOY 42020 REPORTED NORTH WINDS NEAR 12 KNOTS GUSTING TO
NEAR 14 KNOTS WITH SEAS AROUND 2 FEET WITH A 5 SECOND PERIOD AT 13
CDT/18 UTC. HIGH PRESSURE WILL CONTINUE TO DOMINATE OVER THE WESTERN
GULF OF MEXICO THROUGH THE NEXT FEW DAYS. THIS PATTERN WILL ALLOW
LIGHT TO MODERATE WINDS AND LOW TO MODERATE SEAS TO PREVAIL ALONG
THE LOWER TEXAS COAST THROUGH THE FORECAST. SCATTERED SHOWERS AND
THUNDERSTORMS ARE ANTICIPATED DURING A MAJORITY OF THE FORECAST.
&&

.AVIATION...SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING TEMPORARY
MVFR/IFR CONDITIONS TO THE TRIO OF REGIONAL AIRPORTS LATE SATURDAY
MORNING THROUGH SATURDAY AFTERNOON. OTHERWISE...VFR CONDITIONS WITH
LIGHT TO MODERATE WINDS WITH SCATTERED TO BROKEN CLOUDINESS IS
EXPECTED THROUGH A MAJORITY OF THE NEXT 24 HOURS.
&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  81  90  79  89  81 /  30  60  30  40  10
BROWNSVILLE          75  92  77  92  77 /  30  60  30  40  20
HARLINGEN            77  92  77  94  76 /  40  60  30  40  20
MCALLEN              78  94  78  95  76 /  40  60  40  40  20
RIO GRANDE CITY      78  93  78  96  76 /  40  60  40  40  30
SOUTH PADRE ISLAND   82  90  79  88  81 /  30  60  30  40  10
&&

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

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

SYNOPTIC/GRIDS...60
MARINE/AVIATION...66
MESO...ABBOTT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
443 PM CDT FRI SEP 2 2005

TXZ248>257-031100-
BROOKS-COASTAL CAMERON-COASTAL WILLACY-HIDALGO-INLAND CAMERON-
INLAND WILLACY-JIM HOGG-KENEDY-STARR-ZAPATA-
443 PM CDT FRI SEP 2 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR DEEP SOUTH TEXAS.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS...SOME STORMS POSSIBLY
SEVERE...WILL CONTINUE TO DEVELOP ACROSS DEEP SOUTH TEXAS THIS
EVENING. GUSTY WINDS...FREQUENT LIGHTNING AND HEAVY RAINFALL ARE
LIKELY IN ANY THUNDERSTORMS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SCATTERED SHOWERS AND THUNDERSTORMS...SOME STORMS POSSIBLY SEVERE
...WILL CONTINUE THROUGH SUNDAY...MAINLY DURING THE AFTERNOON HOURS.
GUSTY WINDS...FREQUENT LIGHTNING AND HEAVY RAINFALL ARE LIKELY IN
ANY THUNDERSTORMS. HEAT INDICES OF UP TO 110 DEGREES WILL CONTINUE
EACH AFTERNOON THROUGH THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS WEEKEND.