000
FXUS64 KBRO 150534 AAA
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1234 AM CDT SAT JUN 15 2013

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

.AVIATION...MINOR ADJUSTMENTS MADE TO THE PREVIOUS TAF FORECAST
PACKAGE. DEGRADED CONDITIONS ARE EXPECTED TO DEVELOP DURING THE
REMAINDER OF THE OVERNIGHT HOURS WITH LOW CLOUDINESS FORMING UP
AROUND 1500 FEET WITH LIGHT WINDS AT THE SURFACE. FULL VFR IS
EXPECTED ON SATURDAY WITH RISING CEILINGS AND BREEZY SURFACE
WINDS. THE REVERSE WILL OCCUR TOMORROW NIGHT.
&&

.PREV DISCUSSION... /ISSUED 925 PM CDT FRI JUN 14 2013/

DISCUSSION...
SATELLITE IMAGERY AND SUBJECTIVE ANALYSIS SHOWS AN UPPER-LEVEL
TROUGH AXIS EXTENDS FROM NORTHERN NEW MEXICO INTO NORTHERN
TAMAULIPAS MEXICO AT MID- EVENING. FORCING ASSOCIATED WITH THE
TROUGH IS EXPECTED TO WANE OVER THE NEXT 12 TO 24 HOURS...AS THE
SYSTEM LIFTS TOWARD THE ARKLATEX. AFTER THIS OCCURS...RIDGING
ALOFT...AND A DRIER AIRMASS...IS EXPECTED TO RETURN TO THE
FORECAST AREA.

IN THE MEANTIME...AN ISOLATED TO SCATTERED SMATTERING OF SHOWERS
/AND POSSIBLY A FEW THUNDERSTORMS/ WILL CONTINUE TO BE SEEN. IT
SEEMS THE BEST LOCATION FOR SEEING CONVECTION OVER THE NEXT 6 TO
12 HOURS SHOULD REMAIN ACROSS THE UPPER VALLEY AND ADJACENT AREAS
OF THE BRUSH COUNTRY...CLOSER TO THE BEST SYNOPTIC SCALE FORCING.
AS SUCH...I HAVE MADE ADJUSTMENTS TO PRECIPITATION PROBABILITY
TRENDS THROUGH THE OVERNIGHT HOURS.

IT ALSO STILL LOOKS LIKE STREAMER SHOWERS COULD DEVELOP OVER THE
GULF WATERS AND MOVE ONSHORE BEFORE DISSIPATING MID-MORNING
SATURDAY. PRECIPITATION PROBABILITY TRENDS HAVE ALSO BEEN ADJUSTED
FOR COASTAL AREAS IN THE LOWER VALLEY TO ACCOUNT FOR THIS.

OTHER SENSIBLE WEATHER ELEMENTS APPEAR TO BE IN LINE WITH ONGOING
OBSERVATIONAL TRENDS. A FEW TWEAKS WERE MADE EARLIER THIS EVENING
IN ORDER TO BRING HOURLY GRIDS INTO ALIGNMENT WITH OBSERVATIONAL
TRENDS. HOWEVER...NONE OF THESE CHANGES SIGNIFICANTLY MODIFIED
ONGOING LOW OR HIGH TEMPERATURES.

ISC GRIDS HAVE BEEN SENT AND SHOULD BE POSTED TO THE INTERNET. AN
UPDATED SUITE OF TEXT PRODUCTS WILL BE ISSUED SHORTLY.  /BUTTS/

PREV DISCUSSION... /ISSUED 616 PM CDT FRI JUN 14 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...

OVERVIEW...ISOLD TO SCTD SHRA/TSRA IN/AROUND ZAPATA COUNTY HAVE
MOVED N OF THE AREA EARLY THIS EVENING. LATEST AVAILABLE INFORMATION
SUGGESTS ANOTHER ROUND OF SHRA/TSRA MAY AFFECT TERMINALS W OF US-281
PRIOR TO 15/0600 UTC. DUE TO UNCERTAINTIES IN TIMING/DEVELOPMENT...I
PLAN ON KEEPING ANY MENTION OF CONVECTION OUT OF THE KMFE TAF FOR
NOW. ADDITIONAL /STREAMER/ SHRA MAY DEVELOP OVER THE GULF
OVERNIGHT...AND MOVE ONSHORE BETWEEN 15/0900-1300 UTC. ODDS OF
SEEING SHRA/TSRA SHOULD DIMINISH AFTER 15/1800 UTC AS UPPER LOW
MOVES TOWARD THE ARKLATEX. LOWER CIGS MAY AGAIN RESULT IN MVFR
FLIGHT CATEGORIES OVERNIGHT...BUT SHOULD BECOME VFR AFTER 15/1800
UTC. SE WINDS SHOULD DIMINISH TO LESS THAN 10 KTS. OVERNIGHT...THEN
BECOME 10-15 KTS. SATURDAY.

KBRO TAF...-SHRA POSSIBLE 15/0900-1300 UTC...WITH MVFR CIGS POSSIBLE
AFTER 15/0900 UTC. FLIGHT CATEGORIES SHOULD IMPROVE TO VFR BY
15/1500 UTC AND CONTINUE THROUGH 16/0000 UTC. SE WINDS AROUND 10
KTS. SHOULD INCREASE TO 10-15 KTS. AFTER 15/1500 UTC.

KHRL TAF...ISOLD -SHRA POSSIBLE AROUND 15/1200 UTC...WITH MVFR CIGS
POSSIBLE AFTER 15/0800 UTC. FLIGHT CATEGORIES SHOULD IMPROVE TO VFR
BY 15/1600 UTC AND CONTINUE THROUGH 16/0000 UTC. SE WINDS AROUND 10
KTS. SHOULD INCREASE TO 10-15 KTS. AFTER 15/1500 UTC.

KMFE TAF...MVFR FLIGHT CATEGORIES /DUE TO LOW CIGS/ POSSIBLE AFTER
15/0900 UTC. FLIGHT CATEGORIES SHOULD IMPROVE TO VFR BY 15/1500 UTC
AND CONTINUE THROUGH 16/0000 UTC. SE WINDS WILL LIKELY REMAIN 10-15
KTS. THROUGH 16/0000 UTC. /BUTTS/

PREV DISCUSSION... /ISSUED 226 PM CDT FRI JUN 14 2013/

SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...500MB LOW ACROSS WEST
TEXAS CONTINUES TO PROVIDE UNSETTLED WEATHER ACROSS SOUTHWEST AND
DEEP SOUTH TX THIS AFTERNOON. ISOLATED TO SCATTERED CONVECTION
CONTINUES TO DEVELOP ACROSS THE WESTERN PORTIONS OF THE CWA AND HAVE
ISSUED AN SPS FOR ZAPATA AND STARR COUNTY FOR THIS AFTERNOON INTO
THIS EVENING FOR THE POTENTIAL FOR LOCALIZED FLOODING ACROSS
SOUTHERN ZAPATA AND SOUTHWEST STARR WHERE RADAR ESTIMATES 4 TO 6
INCHES OF RAIN FELL LAST NIGHT.

THE UPPER LEVEL LOW ACROSS WEST TX IS EXPECTED TO MOVE EASTWARD
SATURDAY AS A WEAK TROUGH AND WITH THE LOW TO MID LEVEL MOISTURE
ACROSS THE AREA...A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS WILL
LINGER ACROSS THE RIO GRANDE VALLEY TONIGHT INTO SATURDAY.

LONG TERM /SUNDAY THROUGH FRIDAY/...UPPER LEVEL HIGH PRESSURE
BACK IN CONTROL BY SUNDAY. THE UPPER RIDGE WILL EXTEND FROM BAJA CA
TO FLA. THE RIDGE WILL WEAKEN ACROSS THE GULF COAST STATES MONDAY
AS A BROAD LONG WAVE TROUGH SAGS ACROSS THE AREA ALLOWING THE
CENTER OF THE RIDGE TO REESTABLISHED ACROSS NORTHERN MEXICO. THIS
WILL ALLOW A WEAK COLD FRONT TO SAG INTO NORTHERN TEXAS. SCATTERED
STORMS ASSOCIATED WITH THIS FEATURE WILL STAY WELL NORTH OF SOUTH
TEXAS. WINDS MAY INCREASE SLIGHTLY MON AND TUE AS WEAK LOW
PRESSURE DEVELOPS ACROSS NORTH TEXAS. GFS IS STILL ADVERTISING A
TROPICAL WAVE TO MOVE INTO THE BAY OF CAMPECHE BY LATE WED AND
THU. SYSTEM IS WEAKER AND A BIT FURTHER SOUTH THAN EARLIER RUNS
AND MORE IN LINE WITH OTHER MEDIUM RANGE MODELS. THE SYSTEM COULD
STILL INCREASE ATMOSPHERIC MOISTURE AND PERHAPS A FEW SHOWERS...SO
EXPANDED THE 10 PERCENT SILENT POPS FROM WED NIGHT THROUGH FRIDAY.

WITH DRIER MID LEVELS AND STRONGER INFLUENCE OF THE RIDGE EXPECTED
KEPT TEMPS A COUPLE OF DEGREES ABOVE GFS GUIDANCE AND MORE IN LINE
WITH THE ECMWF. HEAT INDICIES TO RUN FROM 105 TO NEAR 110 ACROSS
THE AREA DURING THE MID AFTERNOON PEAK HEATING.

MARINE...TONIGHT THROUGH SATURDAY NIGHT...SEAS WERE NEAR 3 FEET WITH
SOUTHEAST WINDS NEAR 10 KNOTS AT THE BUOY020 EARLY THIS AFTERNOON.
LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL
WATERS TONIGHT INTO SATURDAY AS WEAK HIGH PRESSURE PREVAILS ACROSS
THE GULF OF MEXICO.

SUNDAY THROUGH FRIDAY...GENERALLY FAVORABLE MARINE CONDITIONS
THROUGH THE EXTENDED PERIODS. DRY FORECAST. NEAR AND OFFSHORE
WINDS MAY GET CLOSE TO 20 KNOTS MONDAY NIGHT OR TUESDAY AS WEAK
SURFACE LOW ACROSS NORTH TEXAS DEVELOPS. SEAS TO RUN 2 TO 4 FEET
THROUGH THE EXTENDED FORECAST.
&&

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

$$

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