National Weather Service Raw Text Product

740 
FXUS64 KBRO 201734 AAC
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1234 PM CDT WED JUN 20 2012

.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&

.AVIATION...SATELLITE AND RADAR IMAGES AS WELL AS SURFACE
OBSERVATIONS INDICATE SHOWERS AND THUNDERSTORMS REMAIN OFFSHORE
THE LOWER TEXAS COAST WITH MOSTLY HIGH CLOUDS ACROSS THE CWA THIS AFTERNOON.
CEILINGS WERE NEAR 3100FT AT KBRO. MORNING CONVECTION APPEARS TO
HAVE STABILIZED THE ATMOSPHERE BUT SURFACE INSTABILITY REMAINS
HIGH ACROSS THE COASTAL SECTIONS. MAY SEE THUNDERSTORMS DEVELOP
ACROSS THE WESTERN PORTIONS OF THE RIO GRANDE VALLEY LATE THIS
AFTERNOON INTO THE EVENING WHERE BREAKS IN THE CLOUD COVER WILL
ALLOW SURFACE INSTABILITY TO INCREASE. IN ADDITION...WEAK 500MB
LOW ACROSS NORTHEAST MEXICO WILL CONTINUE TO BRING MOISTURE ACROSS
THE WESTERN GULF OF MEXICO TOWARDS THE AREA. EXPECT VFR CONDITIONS
TO PREVAIL THE REST OF TODAY THROUGH TONIGHT WITH MVFR CONDITIONS
POSSIBLE WITH THUNDERSTORMS LATE TONIGHT.
&&

.PREV DISCUSSION... /ISSUED 1027 AM CDT WED JUN 20 2012/ 
DISCUSSION...CONVECTION ACROSS THE COASTAL SECTIONS OF THE CWA
EARLIER THIS MORNING APPEARS TO HAVE STABILIZED THE ATMOSPHERE AS
SATELLITE AND RADAR IMAGES INDICATE SHOWERS AND THUNDERSTORMS
CONTINUE TO DEVELOP OFFSHORE THE LOWER TEXAS COAST. THE LACK OF
CLOUD COVER ACROSS THE WESTERN PORTIONS OF THE VALLEY WILL ALLOW
SURFACE INSTABILITY TO INCREASE THIS AFTERNOON AND WILL ADJUST
POPS TO REFLECT THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS TO
DEVELOP LATER TODAY AS THE 500MB LOW/INVERTED TROUGH ACROSS
NORTHEAST MEXICO AND SOUTH TEXAS CONTINUES TO BRING MOISTURE
ACROSS THE WESTERN GULF OF MEXICO INLAND.

PREV DISCUSSION... /ISSUED 652 AM CDT WED JUN 20 2012/ 
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...SHOWERS AND THUNDERSTORMS CONTINUE TO MOVE RAPIDLY NORTH 
OUT OF MEXICO THIS MORNING...WHILE STREAMER SHOWERS CONTINUE TO 
DEVELOP AND MOVE NORTHWEST OVER THE LOWER TEXAS COASTAL WATERS. 
CLOUD COVER IS EXPECTED TO INCREASE THROUGH THE DAY AND ISOLATED 
SHOWERS AND THUNDERSTORMS WILL DEVELOP AS CONVECTION FIRES UP DURING 
DAYTIME HEATING. CONVECTIVE ACTIVITY WILL DIMINISH AS DAYTIME 
HEATING WANES. A BLEND OF VFR AND MVFR CONDITIONS WILL BE LIKELY 
TODAY WITH OCCASIONAL REDUCTIONS OF CEILINGS AND VISIBILITIES WITH 
ANY CONVECTION THAT FORMS.

PREV DISCUSSION... /ISSUED 407 AM CDT WED JUN 20 2012/ 
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...AMENDED TAFS FOR KBRO AND KHRL TO REFLECT RAPIDLY
MOVING SHOWERS AND THUNDERSTORMS FROM MEXICO.

PREV DISCUSSION... /ISSUED 344 AM CDT WED JUN 20 2012/ 

SHORT TERM /TODAY THROUGH THURSDAY/...UPPER LEVEL LOW WILL CONTINUE 
TO REMAIN OVER THE AREA TODAY AND THURSDAY ALLOWING FOR AN EASTERLY 
FLOW TO ADVECT DEEPER MOISTURE INTO THE REGION AND PROVIDING AN 
INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE RIO GRANDE 
VALLEY AND DEEP SOUTH TEXAS. STREAMER SHOWERS DEVELOPING AND MOVING 
NORTHWEST OVER THE LOWER TEXAS COASTAL WATERS HAVE PRIMARILY STAYED 
OVER THE WATER THUS FAR THIS MORNING WITH ANY SHOWERS THAT DO MOVE OVER 
LAND DISSIPATING QUICKLY...HOWEVER ONCE DAYTIME HEATING BEGINS MORE 
SHOWERS WILL MOVE ON LAND. GFS AND NAM DIVERGE ON POPS TODAY SO TOOK 
THE AVERAGE OF THE TWO. THURSDAY CONTINUES TO BE THE DAY WITH THE 
GREATEST POPS...LIGHT EASTERLY WINDS AND DEEP MOISTURE ON THURSDAY 
WILL ALLOW A SEABREEZE BOUNDARY TO PUSH INLAND PROVIDING A FOCAL 
POINT FOR SHOWERS AND THUNDERSTORMS DEVELOP ALONG. OTHER THAN 
ADJUSTING POPS DID NOT CHANGE MUCH WITH THE INHERITED FORECAST 
PACKAGE.

LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...THE OPPORTUNITY FOR
SHOWERS AND THUNDERSTORMS WILL CONTINUE FOR THURSDAY NIGHT AS A
MID-LEVEL LOW PRESSURE SYSTEM CENTERED OVER THE NEIGHBORING STATES
OF NUEVO LEON AND TAMAULIPAS IN MEXICO DISSIPATES. RAINFALL CHANCES
WILL END ON FRIDAY...WITH DRY WEATHER PREVAILING THROUGH EARLY NEXT
WEEK...AS PRECIPITABLE WATER VALUES PLUNGE ACROSS DEEP SOUTH TEXAS
AND THE RIO GRANDE VALLEY WHILE MID-LEVEL HIGH PRESSURE CENTERED
OVER NEW MEXICO AND THE TEXAS PANHANDLE STRENGTHENS AND BUILDS
FARTHER SOUTH. 

MARINE...TODAY THROUGH THURSDAY...BUOY020 WAS REPORTING SEAS NEAR 5 
FEET WITH SOUTHEAST WINDS NEAR 15 KNOTS OVERNIGHT. MODERATE SOUTHEAST
WINDS AND MODERATE SEAS WILL CONTINUE TODAY AS HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTS WITH LOWER PRESSURE INLAND. THE PRESSURE
GRADIENT BEGINS TO WEAKEN TONIGHT AND WINDS DECREASE AND SHIFT TO THE
EAST NORTHEAST ON THURSDAY. 

THURSDAY NIGHT THROUGH TUESDAY...MODERATE WINDS AND SEAS VERY EARLY
IN THE FORECAST PERIOD WILL BECOME LIGHT WINDS AND LOW SEAS FOR THE
WEEKEND AND EARLY NEXT WEEK...AS HIGH PRESSURE OVER THE GULF OF
MEXICO INTERACTING WITH LOW PRESSURE OVER WEST TEXAS IS REPLACED BY
WEAK LOW PRESSURE OVER THE WESTERN GULF OF MEXICO. 
&&

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

$$

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