000
FXUS64 KBRO 131729 AAB
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1229 PM CDT THU MAR 13 2014

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

&&

.AVIATION...A FEW CLOUDS ATTEMPTING TO DEVELOP IN SLOWLY
INCREASING MOISTURE...BUT NO MORE THAN SCT AROUND 500 THIS
AFTERNOON. SKIES WILL AGAIN CLEAR THIS EVENING AND EARLY
OVERNIGHT...BEFORE MORE CLOUDS DRIFT IN FROM THE EAST FOR KBRO AND
KHRL. ANY CIGS WOULD REMAIN AROUND 3000 FEET. LIGHT EAST WINDS
AROUND 10 KNOTS WILL CONTINUE THROUGH SUNSET BEFORE LOWERING TO
AROUND 5KTS.

&&

.PREV DISCUSSION... /ISSUED 621 AM CDT THU MAR 13 2014/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...VFR CONDS THROUGH TONIGHT WITH NO CHANGES TO PREVIOUS
TAFS. EXPECT CLOUDS TO INCREASE ON SOUTHEASTERLY WINDS OVERNIGHT
AOA 09Z WITH MVFR CIG HEIGHTS AND UNRESTRICTED VISIBILITIES. A LOW
CHANCE FOR A SHOWER AT KBRO AND KHRL AT THE TAIL END OF THE TAF
PERIOD AS WELL.

PREV DISCUSSION... /ISSUED 326 AM CDT THU MAR 13 2014/

SHORT TERM /NOW THROUGH FRIDAY/...SFC HIGH PRESSURE WILL MOVE
EASTWARD ACROSS THE SOUTHEAST CONUS TODAY AND OFF THE EASTERN
SEABOARD FRIDAY. LIGHT NORTHERLY WINDS EARLY THIS MORNING WILL
GIVE WAY TO EASTERLY WINDS THIS AFTERNOON. SINCE THIS IS VIRTUALLY
A COOLER WIND OFF THE GULF OF MEXICO...THIS WILL KEEP HIGHS
MODERATED IN THE UPPER 60S TO MIDDLE 70S. OVERALL...A SUNNY AND
PLEASANT DAY IS IN STORE FOR DEEP SOUTH TEXAS TODAY. SOUTHEASTERLY
SFC WINDS RETURN TONIGHT WITH INCREASING MOISTURE UNDERNEATH A
STRENGTHENING INVERSION. AN INCREASE IN LOW CLOUDS IS EXPECTED
WITH A CHANCE FOR PATCHY FOG IN THE RANCH LANDS. PARTLY TO MOSTLY
CLOUDY SKIES WILL RUN INTO FRIDAY WITH A FEW SPRINKLES OR LIGHT
RAIN SHOWERS POSSIBLE IN THE MORNING MAINLY ALONG AND EAST OF HWY
77. SFC WINDS STRENGTHEN FROM THE SOUTHEAST THROUGH THE DAY WITH
BREEZY CONDITIONS AS LOW PRESSURE STRENGTHENS ACROSS NORTHWESTERN
TEXAS AIDED BY A SHORTWAVE TROUGH ALOFT. THE INCREASE IN WINDS AND
MOISTURE WILL ALLOW HIGHS TO MAKE IT INTO THE LOWER 80S OUT WEST
TO MIDDLE 70S NEAR THE COAST.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY NIGHT/...STILL SEEING
SMALL DIFFERENCES IN THE LONG RANGE MODELS REGARDING A LATE WEEKEND
FRONTAL PASSAGE THROUGH DEEP SOUTH TEXAS AND THE RGV...THOUGH TIMING
SEEMS TO BE MORE SETTLED FOR SUNDAY MORNING BETWEEN DAWN AND NOON.
DUE TO PREVIOUS INCONSISTENCY...CONFIDENCE REMAINS ONLY AVERAGE. A
BLEND OF THE GFS AND ECMWF REMAINS THE PREFERRED COURSE OF ACTION
FOR NOW. UNTIL THEN HOWEVER...BENIGN WEATHER WILL START OUT THE LONG
TERM FRIDAY NIGHT...WITH A PRELIMINARY FRONT ENTERING NORTHWEST
TEXAS UNDER A SHALLOW SHORT WAVE TROUGH. LGT TO MODERATE SOUTHEAST
WINDS AND MOSTLY CLEAR SKIES WILL BE ON TAP LOCALLY...WITH OVERNIGHT
LOW TEMPS NEAR 60...YIELDING A NONDESCRIPT START TO THE LONG TERM.

HIGH TEMPS WILL WARM INTO THE 80S SATURDAY AS WINDS DECREASE AND
CLOUD COVER INCREASES UNDER OVERRUNNING WEST SOUTHWEST FLOW ALOFT.
MOISTURE POOLING ALONG THE COAST WILL BEGET ISLD COASTAL SHOWERS.
FORECAST SOUNDINGS SHOW PWAT TOPPING OUT AROUND 1.38 INCHES WITH A
NEARLY SATURATED BOUNDARY LAYER...SUPPORTING THE MOISTURE POOLING
ASSERTION. A MID LEVEL SHORT WAVE TROUGH WILL AMPLIFY/DEEPEN OVER
THE NORTHERN ROCKIES EARLY SATURDAY...MOVING SOUTH INTO THE SOUTHERN
PLAINS BY EARLY SUNDAY. PRESSURE FALLS WITH THIS SYSTEM WILL MERGE
WITH THOSE OF THE WEAKER EARLIER SYSTEM OVER EAST TEXAS...RETARDING
THE ADVANCE OF A WEAK BOUNDARY OVER CENTRAL TEXAS.

THE DIGGING UPPER LOW WILL SINK FARTHER SOUTH TO SOMEPLACE OVER
NORTHERN MEXICO BY SUNDAY...WHILE STRONG EASTERN PACIFIC RIDGING
ANGLES FROM SOUTHWEST TO NORTHEAST FROM SOUTHERN CALIFORNIA INTO THE
CENTRAL AND NORTHERN HIGH PLAINS. UNSETTLED WEATHER WILL BEGIN TO
DEVELOP LOCALLY ON SUNDAY AS THE LOW DROPS INTO NORTH MEXICO...WITH
DOWNSTREAM DIVERGENCE ALOFT CREATING INSTABILITY ABOVE DEEP SOUTH
TEXAS...JUST AS A SURGE OF HIGH PRESSURE PUSHES THROUGH AS A COLD
FRONT SUNDAY MORNING BETWEEN DAWN AND NOON. HIGH TEMPS SUNDAY MAY
STILL APPROACH 80 BEFORE MUCH COOL AIR ADVECTION GETS GOING ON THE
MODERATE NORTH WINDS EXPECTED BEHIND THE FRONT. THE AIR MASS WILL BE
MORE OF A CONTINENTAL POLAR ORIGIN FROM CANADA AND NOT DIRECTLY OF
ARCTIC ORIGINS. KEPT CONVECTION PROBABILITY IN THE CHANCE CATEGORY
AS INHERITED. TEMPERATURES SUNDAY NIGHT AND MONDAY WILL DIP ABOUT 10
DEGREES...AND A BIT MORE MONDAY NIGHT...INTO THE MID 50S...SLIGHTLY
BELOW NORMAL...WITH COOLER TEMPERATURES REMAINING DOMINANT THROUGH
TUESDAY BEFORE SKIES CLEAR SIGNIFICANTLY AND A WARMING TREND ENSUES.

THE GFS AND ECMWF ARE IN BETTER AGREEMENT THIS TIME AROUND THROUGH
SUNDAY...BUT DIFFERENCES INCREASE BEYOND THEN. THE ECMWF TAKES THE
UPPER LOW FARTHER SOUTH ALONG THE WEST MEXICAN COAST...RESULTING IN
LESS PRECIP CHANCES POST FRONT. DIVERGENCE ALOFT DOWNSTREAM OF THE
MORE NORTHERN GFS LOW SUNDAY NIGHT HELPS KEEP POTENTIAL THUNDER
ACTIVITY PERCOLATING ALONG THE FRONT RANGE OF THE SIERRA MADRES...
WITH SOME POSSIBLY MOVING TOWARD THE CWA. THE EFFECT IS SHORT LIVED
HOWEVER...AS HIGH PRESSURE SPREADS OVER THE AREA ON MONDAY WITH
PARTIAL CLEARING. BOTH MODELS TAKE THE FILLING UPPER LOW ON AN
EASTERLY TRACK JUST BELOW/SOUTH OF THE CWA ON MONDAY NIGHT AND
TUESDAY...WITH SEASONAL WEATHER FOR THE CWA GOING INTO MID AND LATE
NEXT WEEK.

MARINE...
NOW THROUGH FRIDAY...WINDS AT BUOY 42020 ARE STILL ABOVE 20 KTS
EARLY THIS MORNING WITH SEAS AROUND 7 FEET. SMALL CRAFT ADVISORY
IS IN EFFECT FOR THE 20 TO 60 NM OFFSHORE WATERS THROUGH 12Z/7AM
THIS MORNING. HIGH PRESSURE OVER TEXAS WILL SHIFT EAST ALLOWING
ONSHORE SOUTHEASTERLY FLOW TO RETURN BEGINNING THIS AFTERNOON.
WINDS AND SEAS WILL DECREASE THIS AFTERNOON ALLOWING FAVORABLE
MARINE CONDITIONS TO RETURN LATER TODAY. HOWEVER...SMALL CRAFT
SHOULD EXERCISE CAUTION THURSDAY NIGHT AS WINDS INCREASE IN
INTENSITY. LOW PRESSURE STRENGTHENS IN WEST TEXAS FRIDAY WHICH MAY
KEEP WINDS UP A LITTLE BIT WITH EXERCISE CAUTION CONDITIONS
POSSIBLE INTO FRIDAY.

FRIDAY NIGHT THROUGH MONDAY NIGHT...HIGH PRESSURE OVER THE NORTH
GULF WILL INTERACT WITH LOWER PRESSURE OVER NORTHWEST TX RESULTING
IN MODERATE SOUTHEAST WINDS AND SEAS. A SHORT WAVE TROUGH MOVING
ACROSS NORTH TEXAS FRIDAY NIGHT WILL SHIFT UNDERLYING SURFACE LOW
PRESSURE AND A TRAILING COLD FRONT EAST...WITH EXERCISE CAUTION
CONDITIONS LIKELY ON THE GULF DUE TO THE TIGHTER GRADIENT. COASTAL
SHOWERS WILL BE POSSIBLE AS WELL. THE FRONT WILL PUSH INTO SOUTH
TEXAS SATURDAY BUT WILL STALL IN WAIT FOR ANOTHER...STRONGER SYSTEM
MOVING SOUTH OVER THE PLAINS. WINDS ON SATURDAY WILL THEREFORE RELAX
A BIT. A COLD FRONT WILL PUSH THROUGH SUNDAY...WITH STRONG NORTHEAST
WINDS AND BUILDING SEAS...AS WELL AS UNSETTLED WEATHER IN THE FORM
OF SHOWERS AND THUNDERSTORMS DUE TO THE DIVERGENCE AHEAD OF AN UPPER
LOW TO THE WEST. SMALL CRAFT ADVISORY CONDITIONS WILL BE PROBABLE
SUNDAY THROUGH MONDAY IN THE WAKE OF THE COLD FRONT. HIGH PRESSURE
WILL SPREAD OVER THE GULF BY MONDAY NIGHT...RESULTING IN IMPROVED
CONDITIONS.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...HIGH RIP CURRENT RISK UNTIL 5 PM CDT THIS AFTERNOON FOR TXZ256-
     257.

GM...NONE.
&&

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
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