Area Forecast Discussion
Issued by NWS Brownsville, TX

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FXUS64 KBRO 270547 AAB
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1247 AM CDT WED MAY 27 2015

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

&&

.AVIATION...LOWER CEILINGS HAVE FILLED IN WITH LOW LEVEL INVERSION
SETTING UP AROUND 2500 FEET. MVFR CIGS TO PERSIST THROUGH THE
NIGHT BEGINNING TO BREAK AROUND MID MORNING. A FEW STREAMER
SHOWERS COULD APPROACH KBRO AND KHRL AFTER SUNRISE BUT THEY SHOULD
BE CIRCUMNAVIGABLE. VFR CONDITIONS RESUME WITH A SCT- BKN CUMULUS
DECK BY MID MORNING BECOMING FEW-SCT LATE AFTERNOON. LIGHTER
SOUTHEAST WINDS WITH GUSTS OF 15 TO 20 KNOTS AT BEST.

&&

.PREV DISCUSSION... /ISSUED 613 PM CDT TUE MAY 26 2015/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...ONLY CHANGES NEEDED TO PREVIOUS SET OF TAFS WERE TO
INITIAL CONDITIONS. PREVIOUS AVIATION DISCUSSION FOLLOWS...

PRETTY MUCH SAME STORY DIFFERENT DAY. MVFR CLOUDS HAVE LIFTED TO
VFR THIS AFTERNOON BUT CEILINGS REMAIN ESPECIALLY NORTH OF THE
TERMINALS BUT STILL COMING IN BROKEN FROM TIME TO TIME OVER THEM.
EXPECT THE CLOUDS TO MIX OUT TO SCATTERED FOR THE BALANCE OF THE
AFTERNOON ALONG WITH A MODERATE SOUTHEAST WIND AND THE USUAL P6SM
HAZY SKIES. OVERNIGHT...THE MVFR CEILINGS RETURN. FOR NOW HAVE
BEST ESTIMATE AT 06Z THOUGH THAT COULD FLUCTUATE A LITTLE EARLIER
OR LATER. OVERNIGHT/EARLY THIS MORNING WORKED OUT FAIRLY WELL WITH
CEILINGS IN THE 12 TO 18 HUNDRED FOOT RANGE SO SEE NO REASON FOR
ANYTHING DIFFERENT WITH A 7 TO 11 KNOT WIND.

MIX OUT MIGHT COME A LITTLE QUICKER ON WEDNESDAY THAN TODAY...BUT
STILL HELD HIGH MVFR CEILINGS THROUGH 11 AM /16Z/ JUST TO BE SAFE
BEFORE RISING TO LOW VFR BUT SCATTERED...WITH SIMILAR MODERATE
SOUTHEAST WINDS TO TODAY.

PREV DISCUSSION... /ISSUED 312 PM CDT TUE MAY 26 2015/

SHORT TERM /NOW THROUGH WEDNESDAY NIGHT/...THE QUIETER TREND
CONTINUES OVERALL...THOUGH THERE IS A POSSIBLE FLY IN THE OINTMENT
THIS EVENING AND PERHAPS OVERNIGHT AS WE`RE WATCHING A SMALL AREA OF
CONVECTION NEAR DEL RIO THAT HAS A MARGINAL POSSIBILITY TO REACH THE
RANCHLANDS THIS EVENING AND OVERNIGHT.  OTHERWISE...WHAT YOU SEE IS
WHAT YOU GET: MUGGY SULTRY NIGHTS AND A HOT STICKY DAY...THOUGH
THERE SHOULD BE A TAD MORE AFTERNOON SUNSHINE WITH EVEN DRIER AIR
MOVING IN ABOVE THE MIXING HEIGHT /3500 TO 4500 FEET/...WHICH SHOULD
BRING ADDITIONAL SUNSHINE AND HEAT THINGS UP A DEGREE OR TWO OVER
TODAY.

FOR TONIGHT...WAS PLANNING STATUS QUO UNTIL LOOKING AT CURRENT
SATELLITE/RADAR TRENDS WITH SOME MINOR FLARE UP IN DEL RIO WHICH IS
DRIFTING EAST SOUTHEAST AT 3 PM.  THAT...COMBINED WITH THE 18Z HRRR
WHICH SHOWS RESIDUE FROM EARLY ACTIVITY POTENTIALLY SETTING OFF MORE
ACTIVITY ACROSS CENTRAL TEXAS THAT *COULD* MOVE AT RIGHT ANGLES TO
THE MEAN WESTERLY FLOW AND TOWARD SOUTH TEXAS BY LATE
EVENING/OVERNIGHT.  THE 12Z ECMWF SHOWS A HINT OF ENHANCED MOISTURE
BY 06Z AS WELL ACROSS SOUTH AND DEEP SOUTH TEXAS...AND GIVEN THE WAY
THIS SPRING HAS GONE PREFER NOT TO DENY THE POSSIBILITY SO HAVE
BLENDED WITH NWS CORPUS CHRISTI WITH SLIGHT CHANCES ACROSS THE
ZAPATA/JIM HOGG/BROOKS/KENEDY RANCHLANDS OVERNIGHT.

SITUATION MAY NEED TO BE WATCHED FURTHER AND WILL DEFER TO ONCOMING
SHIFT...THE RECENTLY ARRIVED ECMWF GUIDANCE INDICATED 50-70 PERCENT
CHANCES IN THE RANCHLANDS BUT DIDN`T WANT TO JUMP THE GUN WITH
LIMITED CONFIDENCE AND SUPPORT.

OTHERWISE...AFTER THE MORNING CLOUDS BURN OFF EXPECT TEMPERATURES TO
RISE INTO THE LOW TO MID 90S WEDNESDAY...THAN DROP BACK INTO THE
CURRENTLY FORECAST 75-80 RANGE OVERNIGHT WEDNESDAY NIGHT. NOT
LOOKING AT ANY RAIN CHANCES WEDNESDAY NIGHT AS 500 MB RIDGE AXIS
BUILDS OVER ALL OF SOUTH TEXAS AND DRIER AIR ALOFT CONTINUES TO POUR
IN.

LONG TERM /THURSDAY THROUGH MONDAY/...A SUBTROPICAL RIDGE OVER THE
NORTHWEST GULF AND TEXAS COAST WILL BEGIN TO FLATTEN ON THURSDAY AS
MID LEVEL TROUGHING OVER THE SOUTHWEST UNITED STATES EDGES EAST.
HIGH PRESSURE CENTERED OVER THE SOUTHEAST UNITED STATES WILL STILL
BE IN CONTROL OVER THE NORTH AND NORTHWEST GULF. SO INITIALLY...
EXPECT SEASONAL WEATHER WITH A MIX OF CLOUDS AND SUN AND NEAR TO
SLIGHTLY WARMER THAN NORMAL TEMPERATURES.

THE PATTERN SHOULD HOLD BEYOND THURSDAY WHILE THE MID LEVEL TROUGH
LOSES SOME OF ITS IDENTITY IN MOVING INTO THE PLAINS. SOME ENERGY
WILL STILL MOVE FROM WEST TO EAST OUT OF MEXICO TOWARD AND OVER THE
RIO GRANDE PLAINS THU NIGHT...TRIGGERING CONVECTION THAT COULD CLIP
THE NORTHWEST CORNER OF THE CWA AND POSSIBLY THE NORTHERN COUNTIES
THROUGH EARLY FRIDAY. AFTER THAT PIECE OF ENERGY MOVES THROUGH
HOWEVER...THERE WILL BE LESS INFLUENCE FROM THE WEST...AND IT WILL
BE MORE LIKELY THAT COASTAL SHOWERS AND SEA BREEZE CONVECTION WILL
BE THE MAIN FORECAST ISSUE BEGINNING SATURDAY AND BEYOND. COULD
STILL SEE SOME NOCTURNAL ACTIVITY OVER THE MEXICAN MOUNTAINS...BUT
LACK OF ORTHOGANAL FLOW ALOFT WILL LIMIT MOVEMENT POTENTIAL TOWARD
THE RGV.

WENT WITH THE SUPERBLEND AS A FRAMEWORK...WHICH HANDLED MOST TRENDS
WELL. INCREASED THE POPS ACROSS THE NORTHWEST AND NORTH SLIGHTLY FOR
THURSDAY NIGHT INTO FRIDAY TO CAPTURE CONVECTION POTENTIAL FROM THE
SHORT WAVE TRANSITING WEST TO EAST ACROSS OK AND NORTH TO CENTRAL
TX. OTHERWISE...WILL PRIMARILY SEE A CONTINUATION OF A MIX OF CLOUDS
AND SUN WITH NEAR SEASONAL TEMPERATURES. LOWS IN THE 70S AND HIGHS
FROM THE LOWER 80S ALONG THE COAST TO THE LOWER 90S IN THE UPPER
VALLEY.

MARINE /NOW THROUGH WEDNESDAY NIGHT/...SEAS FLIRTED WITH 7 FEET FOR
A LITTLE WHILE LATE THIS MORNING BUT SINCE HAVE DROPPED BACK TO THE
5-6 FOOT RANGE AT BOTH THE 42020 BUOY AND TABS BUOY EAST OF SOUTH
PADRE.  WINDS AS EXPECTED SETTLED IN THE 10 TO 15 KNOT RANGE.
EXPECT MORE OF THE SAME FOR THE NEXT 36 HOURS WITH LITTLE TO CHANGE
THE GRADIENT OR FETCH...THE WEAK LOW IN THE BAY OF CAMPECHE COMBINED
WITH THE LONG FETCH FROM THE WESTWARD EXTENSION OF THE BERMUDA HIGH
WILL KEEP SEAS IN THE MODERATE...4 TO 6 FOOT RANGE...THROUGH THE
PERIOD.  A LITTLE AFTERNOON GUSTINESS FOR THE LAGUNA MADRE BUT
SHOULD REMAIN AT OR BELOW EVEN CAUTION LEVELS THROUGH THE DAY
WEDNESDAY.

THURSDAY THROUGH SATURDAY...SUBTROPICAL RIDGING WILL BUILD OVER THE
NORTHWEST GULF AND TEXAS...WITH HIGH PRESSURE IN CONTROL AT THE SFC.
THIS WILL MAINTAIN A FAIRLY CONSISTENT REGIME OF MODERATE SOUTHEAST
WINDS AND UPPER END MDT WAVE HEIGHTS. SMALL CRAFT EXERCISE CAUTION
CONDITIONS LOOK PRETTY SOLID ON THE GULF MUCH OF THE PERIOD DUE TO
FOUR TO SIX FEET WAVE HEIGHTS. SOUTHEAST WINDS MAY INCREASE SLIGHTLY
THURSDAY NIGHT...APPROACHING 20 KNOTS DUE TO UPSTREAM PRESSURE FALLS
IN ADVANCE OF UPPER TROUGHING OVER THE SOUTHWEST U.S. CONVECTIVE
ACTIVITY OVER THE GULF WILL INCREASE ON SATURDAY...WITH A FEW MORE
SHOWERS AND/OR TSTMS MOVING INTO THE LOWER TEXAS COASTAL WATERS.

&&

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

$$

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