000
FXUS64 KBRO 091132
AFDBRO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
532 AM CST MON DEC 9 2013

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

&&

.AVIATION...OVERRUNNING CONDITIONS OVER DEEP SOUTH TEXAS WILL LEAD
TO LIFR/IFR CONDITIONS FOR MOST OF THE DAY TODAY WITH DRIZZLE THIS
MORNING AND LIGHT FOG. A BRIEF STINT OF MVFR WILL BE POSSIBLE THIS
AFTERNOON AND HAVE BUILT THIS TREND INTO THE TAF BUT CONFIDENCE OF
OCCURRENCE IS MEDIUM AT BEST AND WILL BE RE-EVALUATED BEFORE THE
NEXT TAF CYCLE. A COLD FRONT WILL SWEEP THROUGH LATER THIS
AFTERNOON AND EVENING WITH STRONG NORTH WINDS BEGINNING AROUND 03Z WITH
GUSTS OF 25 KNOTS AND HIGHER POSSIBLE OVERNIGHT.

&&

.PREV DISCUSSION... /ISSUED 304 AM CST MON DEC 9 2013/

SHORT TERM /NOW THROUGH TUESDAY/...WATER VAPOR IMAGERY SHOWS THE
LONG WAVE TROUGH ACROSS THE CENTRAL PLAINS INTO THE INTER MOUNTAIN
WEST WITH A SHORTWAVE TROUGH DIVING DOWN OFF THE CALIFORNIA COAST.
IR IMAGERY AND LOW CLOUD/FOG PRODUCT SHOWS WIDESPREAD LOW CLOUDS
ACROSS MOST OF TAMAULIPAS STATE INTO SOUTHERN AND CENTRAL TEXAS.
AREA RADARS SHOW LIGHT RAIN AND DRIZZLE ACROSS DEEP SOUTH TEXAS
AND THE ADJACENT COASTAL WATERS. TEMPERATURES EARLY THIS MORNING
MAINLY IN THE 40S ACROSS OUR AREA.

SHORTWAVE TROUGH ACROSS THE EASTERN PACIFIC WILL AID IN PINCHING
OFF A MID LEVEL CLOSED LOW AND EFFECTIVELY FORMING A SOUTHERN
STREAM THROUGH TUESDAY WITH SOUTHWESTERLY FLOW IN THE MID LEVELS
CONTINUING. THIS WILL KEEP COASTAL TROUGHING AND A SURFACE LOW OFF
OUR COAST TODAY AND TONIGHT WITH OVERRUNNING CONTINUING. WE WILL
REMAIN SOCKED IN WITH CLOUD COVER TODAY AND TONIGHT WITH CHANCES
FOR LIGHT RAIN AND/OR DRIZZLE...MUCH LIKE THE PAST FEW DAYS. WITH
THE CONTINUED INFLUX OF MOISTURE...HIGHS TODAY WILL INCH HIGHER
WITH 60S IN THE VALLEY AND 50S ELSEWHERE.

SECONDARY SURGE /ANOTHER COLD FRONT/...WILL MAKE ITS WAY THROUGH
THE AREA TONIGHT. WON`T SEE MUCH OF A WIND SHIFT SINCE SURFACE WINDS
WILL ALREADY HAVE A NORTHERLY COMPONENT SO FRONT SHOULD SLIDE ON
THROUGH. BEHIND THE FRONT WILL BE A FRESHENING OF COLDER AIR ON
THE BACK OF A 1035MB HIGH PRESSURE SLIDING DOWN INTO NORTHERN
TEXAS. DRIER AIR WILL WORK IN FROM THE NORTH AND LOWS MONDAY NIGHT
ARE EXPECTED TO DROP INTO THE MID 30S IN THE BRUSH COUNTRY AND
RANCH LANDS WITH LOWER 40S IN THE VALLEY. LIGHT RAIN WILL ACCOMPANY
THE FRONT WITH BETTER CHANCES ALONG THE COAST AND COASTAL WATERS.

THERE WILL BE A MARKED DIFFERENCE IN HIGH TEMPERATURES ON TUESDAY
WITH READINGS SOME 5 TO 10 DEGREES COOLER OVER MONDAY HIGHS. THE
FRONT WILL ALSO TURN OFF THE OVERRUNNING FAUCET WITH NORTHERLY
FLOW UP TO 850 MB. POPS FOR TUESDAY WILL BE RELEGATED TO THE
COASTAL WATERS AND COASTAL AREAS AS SURGE EFFECTIVELY PUSHES
STALLED COLD FRONT TO OUR SOUTH FURTHER SOUTH AND AWAY FROM OUR
AREA. WINDS WILL ALSO BE BREEZY ACROSS MOST OF THE AREA SO
ANOTHER RAW DAY IS IN STORE FOR THE AREA. WITH DEPTH OF MOISTURE
INCREASING TUESDAY ALONG WITH HIGH LEVEL CIRRUS EXPECTED DON`T
THINK WE WILL SEE MUCH SUN IN THE FORECAST EITHER.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY NIGHT/...ZONAL MID
LEVEL FLOW WILL PRESIDE OVER THE SOUTHEAST UNITED STATES TUESDAY
NIGHT...ABOVE HIGH PRESSURE OVER THE SAME AREA...WITH A CUT OFF
LOW OVER SOUTHERN CALIFORNIA/BAJA. THE SAME HIGH PRESSURE WILL
EXTEND BACK OVER EAST AND CENTRAL TEXAS...WITH DRIER AIR TRYING TO
FILTER SOUTH BUT STILL CAPPED BY SOUTHWEST FLOW ALOFT...LEADING TO
OVERCAST SKIES AND UNSEASONABLY COOL TEMPERATURES...ABOUT 10
DEGREES BELOW NORMAL. NONETHELESS...A WARMING TREND WILL BE
UNDERWAY...WITH TEMPERATURES GRADUALLY WARMING TOWARD NORMAL BY
FRIDAY. AS HIGH PRESSURE SHIFTS EAST...GULF WINDS WILL REMAIN
STRONGER THAN THOSE FARTHER TO THE WEST ALONG THE LOWER TEXAS
COAST AND THE NORTHEAST MEXICAN COAST AND INLAND...RESULTING IN A
COASTAL TROUGH...AND SLIGHTLY AMPLIFIED RAIN CHANCES NEAR THE
COAST ON WEDNESDAY. A WEAK RIDGE WILL BUILD OVER TEXAS WEDNESDAY
NIGHT INTO THURSDAY AS THE CUT OFF LOW TO THE WEST BEGINS TO
TRACK OVER ARIZONA...WHILE ANOTHER SHOT OF CANADIAN AIR MOVES
OVER THE OHIO RIVER VALLEY...THOUGH ALSO EXTENDING SOUTH OVER THE
NORTH GULF AND EVEN BACK INTO EAST TEXAS. THE OVERALL IMPACT ON
THE CWA OF THIS HIGH LOCALLY WILL MINIMAL. THE CUTOFF LOW WILL
BEGIN TO OPEN AND EJECT NORTHEAST THURSDAY INTO THURSDAY NIGHT...
SPREADING PRECIP OVER EAST TEXAS...BUT ALSO HELPING LOCAL WINDS
RETURN TO SOUTHEAST AS PRESSURES FALL OVER THE SOUTHERN HIGH
PLAINS. IN THE WAKE OF THE TRANSITING TROUGH TO THE NORTH...A
MORE ZONAL MID LEVEL PATTERN WILL RETURN...WITH PLAINS HIGH
PRESSURE FROM CANADA AND/OR THE PACIFIC NORTHWEST AGAIN FILTERING
INTO THE AREA. THIS TIME TEMPERATURES WILL ONLY BE AFFECTED
SLIGHTLY AS THEY DROP A FEW DEGREES ON SUNDAY AND EARLY MONDAY...
BUT REMAINING NEAR NORMAL OVERALL. ANCHORED THE FORECAST MAINLY
ON THE GFS...WITH SOME INFLUENCE FROM THE ECMWF IN THE FAR
EXTENDED...BUT OVERALL NOT A LOT OF CHANGE WAS MADE TO THE
INHERITED PACKAGE.

MARINE...
NOW THROUGH TUESDAY...MOSTLY MODERATE WINDS AND SEAS WILL PREVAIL
THROUGH THE MORNING HOURS AHEAD OF AN APPROACHING COLD FRONT.
WINDS WILL BEGIN TO STRENGTHEN THIS AFTERNOON WITH SMALL CRAFT
EXERCISE CAUTION CONDITIONS THIS AFTERNOON. AS THE FRONT MOVES
THROUGH LATER TODAY AND TONIGHT...WINDS WILL STRENGTHEN AND SEAS
WILL INCREASE WITH SMALL CRAFT ADVISORIES BEGINNING AT 00Z FOR ALL
LOWER TEXAS COASTAL WATERS WHICH WILL RUN THROUGH TUESDAY.

TUESDAY NIGHT THROUGH THURSDAY NIGHT...1032 MB HIGH PRESSURE
CENTERED ROUGHLY OVER THE LOWER MISSISSIPPI VALLEY AND EXTENDING
INTO EAST AND SOUTH TEXAS WILL ALSO DOMINATE THE NORTH AND WEST
GULF TUESDAY NIGHT...RESULTING IN MODERATE TO FRESH NORTH TO
NORTHEAST WINDS. SMALL CRAFT ADVISORY CONDITIONS WILL PREVAIL.
CONDITIONS WILL IMPROVE TEMPORARILY ON WEDNESDAY...DROPPING JUST
BELOW SMALL CRAFT ADVISORY CONDITIONS...AS THE HIGH PRESSURE
SHIFTS EAST AND THE GRADIENT SLACKENS A BIT OVER THE LOWER TEXAS
COAST...BUT ON ITS HEELS WILL ARRIVE ANOTHER HIGH PRESSURE AIR
MASS MOVING INTO THE SOUTHEAST UNITED STATES AND INFLUENCING THE
NORTH AND WEST GULF. NORTHEAST WINDS WILL AGAIN BECOME FRESH AND
SEAS WILL BUILD TO SEVEN FEET...WITH ADVISORY CONDITIONS ON THE
GULF WATERS IF NOT WEDNESDAY NIGHT THEN BY THURSDAY THROUGH
THURSDAY NIGHT. CONDITIONS WILL IMPROVE LATE IN THE WEEK AS HIGH
PRESSURE SPREADS OVER THE AREA. INTERMITTENT LIGHT RAIN AND
DRIZZLE WILL BE THE RULE FOR THE ENTIRE PERIOD.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO 3 PM
     CST TUESDAY FOR GMZ130-132-135.

     SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST TUESDAY
     FOR GMZ150-155-170-175.

&&

$$

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

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