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000
FXUS64 KBRO 240533 AAA
AFDBRO

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1233 AM CDT FRI MAY 24 2013

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

.AVIATION...ONLY MINOR ADJUSTMENTS MADE TO THE PREVIOUS TAF
PACKAGE REGARDING WIND STRENGTH AND TIMING. OVERALL...MVFR WITH
TEMPO IFR CONTINUE TO BE EXPECTED THROUGH THE REMAINDER OF THE
OVERNIGHT HOURS...AS WINDS DIMINISH TO LIGHT LEVELS. FULL VFR
WILL RESUME ON FRIDAY WITH RISING CEILINGS AND BREEZY SURFACE
WINDS.
&&

.PREV DISCUSSION... /ISSUED 639 PM CDT THU MAY 23 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...AFTERNOON CUMULUS IS WANING AT THIS MOMENT AND HIGH
CIRRUS FROM TSTORMS TO THE WEST IS BEGINNING TO WORK INTO DEEP
SOUTH TEXAS. MVFR CIGS EXPECTED TO DEVELOP AND WORK BACK INTO THE
RIO GRANDE VALLEY THIS EVENING. CIG HEIGHTS AROUND 1500 FEET
EXPECTED WITH BRIEF BOUTS INTO THE IFR CATEGORY OVERNIGHT. A
RETURN TO VFR IS EXPECTED FRIDAY AFTERNOON AND SOUTHEAST WINDS ARE
EXPECTED TO BECOME GUSTY BY MID MORNING AS LOW PRESSURE DEEPENS
ACROSS NORTHEAST MEXICO.

PREV DISCUSSION... /ISSUED 200 PM CDT THU MAY 23 2013/

SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
RIDGING HAS QUICKLY BUILT NORTHWARD ACROSS CENTRAL TEXAS
TODAY...HOLDING IN PLACE THE DRY AIR ABOVE 5000 FEET. BELOW
THIS...SFC HIGH EXTENDING ACROSS THE NORTHERN GULF CONTINUES TO
PROVIDE LONG SE TAP FROM THE GULF...KEEPING DEWPOINTS IN THE LOWER
70S AND DRAWING MORE SMOKE FROM THE SOUTH INTO TEXAS. DAYTIME
HEATING HAS BROUGHT THICKER DAYTIME CU FIELD...WHICH WILL SLOWLY
THIN THROUGH THIS EVENING. AFTER SUNSET...THE CLOUD DECK WILL RETURN
AND LOWER TO 1500 FEET. ALL MODELS ARE CONTINUING TO SHOW A WEAK
VORT RACING NWWD FROM NORTHERN MEXICO THROUGH THE BIG BEND REGION
INTO NORTH TEXAS TOMORROW AND TOMORROW NIGHT. MOST OF THE RIO GRANDE
VALLEY WILL BE DOMINATED TOO MUCH BY THE RIDGE...BUT THERE IS AN
OUTSIDE CHANCE THAT A THUNDERSTORM ON THE SIERRA MADRE MOUNTAINS IN
MEXICO WILL CLIP THE EDGES OF ZAPATA AND JIM HOGG COUNTIES...MAINLY
FRIDAY NIGHT. FEEL THAT THIS THREAT IS MINIMAL...SO HAVE KEPT ONLY
10 PERCENT CHANCES FOR THOSE AREAS FRIDAY NIGHT. HAVE ALSO ADDED 10
CHANCE FOR CAMERON COUNTY FRIDAY NIGHT AS THE INSTABILITY MAY HELP
SPARK A STREAMER SHOWER OR TWO LATER OVERNIGHT. /64/

LONG TERM /SATURDAY THROUGH THURSDAY/...
AS WE HEAD INTO THE LONG TERM PORTION OF THE FORECAST...A WEAK
SHORTWAVE TROUGH IS EXPECTED TO MOVE FROM THE BIG BEND TO THE
ARKLATEX SATURDAY.  WHEN IT MOVES ACROSS THE STATE...THIS FEATURE
COULD GENERATE A BIT OF CONVECTION NORTH OF OUR AREA.  THE BIG
QUESTION REVOLVES AROUND WHETHER ANY PRECIPITATION COULD WANDER INTO
NORTHERN/WESTERN PARTS OF OUR AREA.

PRECIPITABLE WATER VALUES REMAIN ON THE HIGH END OF NORMAL FOR LATE
MAY/EARLY JUNE...WITH FORECAST VALUES HOVERING AROND THE 1.5 INCH
MARK.  FORECAST SOUNDINGS MAY INDICATE A BIT OF INSTABILITY...BUT
THEY ALSO SHOW A SUBSIDENCE INVERSION PRESENT DURING THE MORNING
HOURS.  BY THE TIME THE INVERSION WEAKENS...I FEEL THE /WEAKENING/
SHORTWAVE TROUGH WILL BE TOO FAR AWAY TO HAVE MUCH OF AN EFFECT ON
OUR WEATHER LOCALLY.

EVEN WITH ALL OF THIS SAID...IT IS NOT OUT OF THE REALM OF
POSSIBILITY TO SEE A BIT OF CONVECTION WANDER SOUTHWARD TOWARD
NORTHERN PARTS OF ZAPATA OR JIM HOGG COUNTIES SATURDAY MORNING.
WITH THE SOUTHEASTERLY LOW-LEVEL FLOW...A FEW STREAMER SHOWERS
CANNOT BE DISCOUNTED OVER THE COASTAL AREAS.  GIVEN MY CONFIDENCE IN
ALL OF THIS HAPPENING...I HAVE DECIDED TO INTRODUCE SOME LOW-GRADE
PRECIPITATION PROBABILITIES TO THESE AREAS.  RIGHT NOW...I WILL KEEP
THE ODDS OF SEEING SHOWERS UNDER 15 PERCENT.

UPPER RIDGING IS EXPECTED TO AMPLIFY OVER OUR AREA SUNDAY...AS AN
UPPER LEVEL TROUGH DEEPENS OVER THE WESTERN UNITED STATES EARLY NEXT
WEEK.  WHEN THIS OCCURS...WE WILL LIKELY SEE A DEVELOPING TROUGH OF
LOW PRESSURE AT THE SURFACE ACROSS PARTS OF WEST TEXAS.  THIS MAY
ALLOW SOUTHEASTERLY WINDS TO INCREASE ACROSS OUR AREA BY MEMORIAL
DAY.  GIVEN THE EXPECTED PRESSURE GRADIENT...I WOULD NOT BE
SURPRISED TO SEE BREEZY CONDITIONS CONTINUE THROUGH THE MIDDLE OF
NEXT WEEK.

OTHERWISE...MAINLY DRY WEATHER CONDITIONS ARE EXPECTED FOR MUCH OF
THE UPCOMING WEEK...EVEN AS THE RIDGE STARTS SLIDING EAST BY DAY
6/7.  ONGOING FORECAST TEMPERATURES APPEARED TO BE IN THE
BALLPARK...WITH ONLY SOME MINOR TWEAKS MADE HERE OR THERE.  /53/

MARINE...

TONIGHT THROUGH FRIDAY NIGHT...
DOMINANT SFC HIGH ACROSS THE GULF WILL CONTINUE THE SE FLOW THROUGH
FRIDAY NIGHT. THE LACK OF AN OPPOSING LOW PRESSURE AREA TO THE NW
WILL KEEP SPEEDS IN THE 10 TO 15 KNOT RANGE THROUGH THE PERIOD...IN
TURN KEEPING SEAS GENERALLY BETWEEN 3 AND 5 FEET. LOWER VISIBILITY
WILL CONTINUE TO BE NOTED ACROSS MARINE AREAS FROM SMOKE FROM THE
SOUTHEAST. /64/

SATURDAY THROUGH TUESDAY...
MODERATE WINDS AND SEAS ARE EXPECTED THROUGH THE UPCOMING WEEKEND...
WITH COMBINED SEAS AVERAGING 4 FEET OR LESS.  A STRENGTHENING
PRESSURE GRADIENT WILL LIKELY RESULT IN BUILDING WINDS AND SEAS FOR
EARLY NEXT WEEK...WHICH MAY NECESSITATE SMALL CRAFT TO EXERCISE
CAUTION OR THE ISSUANCE OF SMALL CRAFT ADVISORIES.  A FEW ISOLATED
SHOWERS MAY BE SEEN OVER THE MARINE AREA DURING THE MORNING HOURS
THIS WEEKEND.  GIVEN THE UNCERTAINTY IN PRECIPITATION HAPPENING...
ANY PROBABILITIES WILL BE KEPT UNDER 15 PERCENT.  /53/
&&

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

$$

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