000
FXUS64 KBRO 170538
AFDBRO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1238 AM CDT MON JUN 17 2013

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

&&

.AVIATION...LATEST SATELLITE IMAGERY SHOWS LOW LEVEL CLOUDS
AROUND 1500 TO 1800 FEET STARTING TO DEVELOP TO THE NORTH
AND WEST OF KHBV AND KAPY. ACROSS KMFE...KHRL AND KBRO...
EXPECT MVFR CONDITIONS TO GRADUALLY DEVELOP THROUGH THE
NIGHT. SE WINDS WILL PREVAIL THROUGH THE NIGHT BETWEEN 10
KNOTS OR LESS AT TIMES. NO PRECIPITATION EXPECTED AT THIS
TIME AS RIDGE BUILDS ACROSS THE FORECAST AREA.

&&

.PREV DISCUSSION... /ISSUED 647 PM CDT SUN JUN 16 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...SATELLITE IMAGES AND SURFACE OBSERVATIONS INDICATE
MOSTLY CLEAR SKIES ACROSS THE CWA EARLY THIS EVENING. CEILINGS
WERE NEAR 7000FT AT KBKS. EXPECT VFR CONDITIONS TO PREVAIL TONIGHT
INTO MONDAY AS 500MB RIDGE ACROSS NORTHERN MEXICO AND ACROSS THE
GULF OF MEXICO PROVIDES SUBSIDENCE ACROSS THE RIO GRANDE VALLEY.

PREV DISCUSSION... /ISSUED 235 PM CDT SUN JUN 16 2013/
SHORT TERM /NOW THROUGH MONDAY NIGHT/...WEAK RIDGING REMAINS JUST
OFF TO THE EAST ACROSS THE GULF...WHILE REMNANTS OF THE TROUGH
REMAIN STUBBORNLY IN PLACE...WITH THE AXIS ROUGHLY ALONG I-35
ACROSS THE STATE. THE DRIEST AIR IS BOTTLED UP WITH THE CORE OF
THE RIDGE...SO MOISTURE IS STILL IN PLACE FOR SOME SHOWERS ALONG
THE SEABREEZE CURRENTLY IN KENEDY COUNTY. WITH CONVECTIVE TEMP IN
THE LOW 90S...SHOWERS WILL END NEAR SUNSET. MINIMAL CAPPING NOTED
IN SOUNDING WILL PROVIDE MOSTLY CLEAR SKIES OVERNIGHT...WITH BRIEF
THICKENING RIGHT AROUND SUNRISE. THE RIDGE SHIFTS
WESTWARD...FINALLY OVERPOWERING THE TROUGH AND DRAGGING MUCH DRIER
AIR /PW LESS THAN 1.4 INCHES/ INTO THE REGION OVERNIGHT. THIS WILL
END ANY SHOWER FORMATION ALONG THE SEABREEZE...BUT WILL ALSO ALLOW
TEMPERATURES TO INCREASE ANOTHER DEGREE OR TWO FROM TODAY/S HIGHS.
MOST OF THE REGION WEST OF US281 WILL SEE HIGHS ABOVE 100 DEGREES
TOMORROW AFTERNOON.

LONG TERM /TUESDAY THROUGH SUNDAY/...PERSISTENCE...PERSISTENCE...
PERSISTENCE IS THE FORECAST MODEL OF CHOICE. MID LEVEL HIGH
PRESSURE WILL CONTINUE TO DOMINATE WEATHER CONDITIONS ACROSS THE
RGV AND DEEP SOUTH TEXAS. THE RIDGE EXTENDING ACROSS MEXICO INTO
SOUTHWEST TEXAS TUESDAY WILL LIKELY STRENGTHEN AND BECOME
CENTERED OVER TEXAS BY THU. BY SUNDAY...THE RIDGE SHIFTS A BIT
NORTH INTO OKLAHOMA AND A BROAD INVERTED TROUGH IS ADVERTISED TO
DEVELOP ACROSS THE WESTERN GULF. IT IS POSSIBLE IN THIS SCENARIO
THAT THE INCREASED MOISTURE AND LESS SUBSIDENCE COULD TRANSLATE
INTO A BIT MORE ACTIVE SEA BREEZE FRONT ON SUNDAY. THEREFORE...I
INSERTED SILENT 10 PERCENT POPS FOR SUNDAY TO AN OTHERWISE ZERO
POP EXTENDED FORECAST.

WITH DRIER MID LEVELS AND GREATER INFLUENCE OF THE 5H RIDGE TEMPS
WILL WARM ACCORDINGLY. INHERITED AND/OR ECMWF NUMBERS SEEM MORE
PLAUSIBLE THAN THE LESS HOT GFS GUIDANCE. HIGH TEMPS VERY NEAR OR
ABOVE 100 ACROSS AREAS WEST OF HIGHWAY 77...TRENDING TO THE LOWER
90S ALONG THE COAST.

TROPICAL WAVE OVER THE WESTERN CARIBBEAN HAS BECOME BETTER
ORGANIZED OVER THE LAST 24 HOURS AS IT CONTINUES TO MOVE SLOWLY
WESTWARD. MODELS IN BETTER AGREEMENT THAT PART OF THIS SYSTEM MAY
EMERGE IN THE BAY OF CAMPECHE BY THU...BUT WILL BE POORLY DEFINED
AND LIKELY TO STAY FAR ENOUGH SOUTH NOT TO HAVE ANY DIRECT IMPACTS
TO THE RGV. IN OTHER WORDS...INCREASED RAIN CHANCES FROM THIS
SYSTEM DO NOT LOOK GOOD AT THIS POINT.

MARINE...NOW THROUGH MONDAY NIGHT...WINDS FOR THE GULF WATERS
REMAIN MODEST...WHILE THE LAGUNA EXPERIENCES EFFECTS OF THE
SEABREEZE DRAGGING COOLER AIR INLAND AT 15 TO 20 KNOTS. SMALL CRAFT
SHOULD EXERCISE CAUTION ON THE LAGUNA THROUGH SUNSET. SEAS OFFSHORE
REMAIN BOTTLED IN THE 3 TO 4 FOOT RANGE...WITH MINIMAL FLUCTUATION
THROUGH THE NEXT 36 HOURS. BREEZY CONDITIONS TOMORROW WILL NEED
CAUTION STATEMENTS FOR THE LAGUNA MADRE.

TUESDAY THROUGH SUNDAY...LIGHT TO MODERATE WINDS AND SEAS THROUGH
THE EXTENDED FORECAST PERIOD. SMALL CRAFT MAY NEED TO EXERCISE
CAUTION FOR A PORTION OF THE GULF OF MEXICO WATERS EAST OF PADRE
ISLAND FROM WEDNESDAY NIGHT THROUGH THURSDAY NIGHT DUE TO SWELLS
GENERATED FROM AN AREA OF DISTURBED WEATHER AT THAT TIME OVER THE
BAY OF CAMPECHE...SO CURRENT WAVE HEIGHT FORECASTS WERE
MAINTAINED. HOWEVER...LATEST MODEL RUNS INDICATE PERHAPS EVEN
LESSER IMPACTS FROM THIS SYSTEM.

&&

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

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV

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