000
FXUS64 KBRO 091725 AAC
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1225 PM CDT SUN MAR 9 2014

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

&&

.AVIATION...LITTLE CHANGE IN CONDITIONS ARE EXPECTED THROUGH THE
TAF PERIOD. LOW PRESSURE JUST OFF THE COAST WILL REMAIN STATIONARY
THROUGH THE NIGHT WITH IFR CEILINGS EXPECTED TO HOLD. LATE IN THE
OVERNIGHT A PERIOD OF SOMEWHAT HEAVIER RAIN AND LOWER CEILINGS
LOOKS LIKELY NEAR THE COAST AND POSSIBLE FURTHER INLAND WITH CIGS
DROPPING INTO THE LIFR RANGE REBOUNDING TO IFR BY MID MORNING
MONDAY. CONFIDENCE IN SUCH A SUBTLE CHANGE IS LOW AT THAT TIME RANGE
BUT CIGS RANGING BETWEEN ABOUT 400 AND 900 FT WITH LIGHT RAIN AND
DRIZZLE IS PRETTY HIGH CONFIDENCE THROUGH THIS TIME TOMORROW.
WINDS WILL BE OUT OF THE NORTHWEST GUSTING TO AROUND 20 KNOTS
THROUGH THIS AFTERNOON DECREASING SOME AFTER SUNSET. /68-JGG/

&&

.PREV DISCUSSION... /ISSUED 844 AM CDT SUN MAR 9 2014/

DISCUSSION...VISIBLE SATELLITE AND OBS TRENDS APPEAR TO SUGGEST
STRENGTHENING COASTAL TROUGHING WITH AN AXIS PARALLEL TO THE COAST
ABOUT 60 MILES OFFSHORE. WITH PLENTIFUL MOISTURE AND A LARGE UPPER
TROUGH/CLOSED LOW TO THE WEST WITH EMBEDDED PERTURBATIONS AHEAD OF
IT EXPECT THAT TROUGHING WILL CONTINUE TO INTENSIFY THROUGH THE
NEXT 3 TO 6 HOURS WHICH WILL FURTHER ENHANCE OVERRUNNING WITH MID
LEVEL ASCENT PROVIDING INSTABILITY TO WORK WITH THE TROUGHING/LOW
CONVERGENCE TO PRODUCE A FEW ENHANCED SHOWERS. GOING FORECAST WITH
VERY HIGH POPS AND LOW QPF LOOKS RIGHT ON. LOWERED MAXES A FEW
DEGREES NEAR THE COAST DUE TO TRENDS SO FAR THIS MORNING AND
EXPECTED PERSISTENT THICK CLOUD COVER. /68-JGG/

PREV DISCUSSION... /ISSUED 639 AM CDT SUN MAR 9 2014/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...COLD FRONT HAS PASSED ALL LOCATIONS THIS MORNING...WITH
WINDS NOW NORTHERLY 15G20KTS. BREEZY CONDITIONS WILL CONTINUE
THROUGH SUNSET BEFORE LOWERING TO AROUND 10 KNOTS WITH 15KT GUSTS
CONTINUING. LOW CLOUDS 600 TO 900 FEET CONTINUE WITH MINIMAL
MODERATION THROUGH THE NEXT 24 HOURS. FIRST WAVE OF RAINFALL IS
PRETTY MUCH DONE...BUT -RA AND -DZ EXPECTED TO SPREAD OVER THE
REGION LATER THIS MORNING AND CONTINUE INTO TONIGHT.

PREV DISCUSSION... /ISSUED 404 AM CDT SUN MAR 9 2014/

SHORT TERM /NOW THROUGH MONDAY/...THE COLD FRONT CONTINUES TO
MOVE ACROSS DEEP SOUTH TEXAS...CURRENTLY THROUGH WESLACO AND JUST
NOW ARRIVING AT KHRL. LARGE RAIN SHIELD CONTINUES TO MOVE EASTWARD
BEHIND THE FRONT...WITH A FEW SHOWERS...ENHANCED BY MIDLEVEL
IMPULSE ALOFT...SPARKING A FEW LIGHTNING STRIKES IN THE HEAVIEST
SHOWERS. THE FRONT WILL MOVE OFFSHORE AND TRANSITION MORE TO A
COASTAL TROUGH. THE IMPULSE ALOFT WILL MOVE OFF TO THE NE...WITH
THE RAINFALL TRANSITIONING TO A LIGHT RAIN/DRIZZLE OVERRUNNING
PATTERN. LIKELY RAINFALL WILL CONTINUE FOR THE REGION...AND WILL
HOLD A SLIGHT CHANCE FOR THUNDER FOR THE IMMEDIATE COAST AND
OFFSHORE INTO THE MORNING HOURS. DENSE CLOUD COVER...CAA...AND
LIGHT PRECIP WILL KEEP TEMPERATURES WELL BELOW NORMAL...WITH HIGHS
TODAY GENERALLY HOVERING IN THE UPPER 40S AND LOWER 50S. MINIMAL
DIURNAL CHANGE OVERNIGHT...WITH LOWS MAYBE INTO THE MID 40S. CLOUD
COVER REMAINS DENSE INTO TOMORROW...WITH ANOTHER MINIMAL DIURNAL
DAY. HIGHS WILL ONLY RISE INTO THE MID TO UPPER 50S AREAWIDE.
LIGHT RAIN AND DRIZZLE CONTINUES WITH THE COASTAL TROUGH
OVERRUNNING CONTINUING. THE H5 CUTOFF LOW IN NORTH MEXICO WILL
BEGIN TO EJECT EASTWARD AT THE END OF THE SHORT TERM...BRINGING
SOME MIDLEVEL ENERGY NEAR THE CORE OF THE LOW. THIS MAY BRING
ENOUGH UVV FOR SOME ELEVATED CONVECTION DURING THE DAY MONDAY.
WILL ADD SOME SLT CHANCE THUNDER TO THE LIKELY RAINFALL OCCURRING
MONDAY AFTERNOON.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...MODELS IN GOOD
AGREEMENT WITH THE LONG TERM WITH THE OVERALL MID LEVEL PATTERN TO
TRANSITION INTO A QUIET ZONAL FLOW STARTING WEDNESDAY. ONE LAST
FRONT MOVES THROUGH MID WEEK THAN WE WILL HAVE WAIT UNTIL NEXT
SUNDAY OR MONDAY FOR THE NEXT ONE. OVERALL...A NICE SPRING WEEK
WITH DRIER AND MILD CONDITIONS.

MID LEVEL TROUGH FINALLY MOVES EAST OF TEXAS TUESDAY WITH RAIN
ENDING WEST TO EAST MONDAY NIGHT. AS THE MID LEVEL FLOW BECOMES
MORE WESTERLY TEMPERATURES IN WAKE OF THE TROUGH WARM INSTEAD OF
COOL OFF. DRIER CONDITIONS MOVE IN WITH THE WESTERLY WINDS
RESULTING IN TEMPERATURES WARMING SIGNIFICANTLY OVER MONDAY. IN
WAKE OF THE LOW LATITUDE TROUGH A NORTHERN STREAM TROUGH DIGS INTO
THE SOUTHERN PLAINS SWEEPING A FRONT ACROSS WEDNESDAY. AGAIN
MODELS IN GOOD AGREEMENT WITH THE FRONTAL PASSAGE SOMETIME
WEDNESDAY MORNING. NO MOISTURE RETURN IN ADVANCE OF THE FRONT SO
THIS FRONT WILL BE DRY WITH TEMPERATURES DROPPING ABOUT 10 DEGREES
BELOW NORMAL. SURFACE HIGH PRESSURE SETTLES OVER THE TOP OF US
THURSDAY MORNING SETTING UP A COOL MORNING. THE HIGH TRACKS EAST
THURSDAY AND FRIDAY WITH A WARMING TREND AS WINDS RETURN FROM THE
SOUTHEAST. THIS EVENTUALLY LEADS INTO AN INCREASINGLY MOISTURE END
OF THE WEEK WITH ONLY A SMALL CHANCE OF A SHOWER OR TWO BUT
NOTHING AS WIDESPREAD AS WHAT WE ARE SEEING CURRENTLY.

MARINE...NOW THROUGH MONDAY...COLD FRONT PASSING OFFSHORE ATTM WILL
INCREASE NORTH WINDS TO 20KTS. SEAS WILL INCREASE TO 6 TO 8 FEET
OFFSHORE LATER THIS MORNING. SMALL CRAFT ADVISORIES GO INTO EFFECT
AT 4AM AND CONTINUE INTO THE LATE AFTERNOON WHEN WINDS BEGIN TO
RELAX. COASTAL TROUGHING WILL SET UP OVERNIGHT...WITH NORTHERLY
FLOW CONTINUING INTO MONDAY AROUND 15 KNOTS.

RAIN SHIELD MOVING OFFSHORE AT THIS TIME...WITH WIDESPREAD RAINFALL
EXPECTED THROUGH MOST OF THE DAY. AN ISOLATED CLOUD TO SFC LIGHTNING
STRIKE IS POSSIBLE. RAIN WILL BECOME LIGHTER OVERNIGHT BUT WILL
REMAIN WIDESPREAD.

MONDAY NIGHT THROUGH THURSDAY...RAIN MOVES EAST TUESDAY WITH
SURFACE TROUGH TRACKING EAST. LIGHT TO MODERATE WESTERLY FLOW TO
RESULT IN IMPROVING MARINE CONDITIONS. THE GOOD CONDITIONS WILL BE
SHORT LIVED AS A STRONGER COLD FRONT MOVES THROUGH WEDNESDAY.
SMALL CRAFT ADVISORIES ARE LIKELY THROUGH THE DAY WEDNESDAY. HIGH
PRESSURE BUILDS IN QUICKLY WITH RAPIDLY IMPROVING CONDITIONS BY
THURSDAY MORNING.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM CDT THIS AFTERNOON FOR
     GMZ130-132-135.

     SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ150-155-
     170-175.

&&

$$

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