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000
FXUS64 KHGX 151722
AFDHGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1222 PM CDT SAT JUN 15 2013

.AVIATION...
ISOLATED SHRA/TSRA POSSIBLE THIS AFTERNOON THROUGH EARLY THIS EVENING
DURING PEAK HEATING. NOT VERY CONFIDENT AS TO WHERE BEST SETUP WILL
OCCUR. OTHERWISE...VFR WITH S/SE WINDS IN A 4 TO 9 KNOT RANGE. MAINLY
VFR TONIGHT WITH SOME MVFR CEILINGS/VISIBILITIES POSSIBLE FOR A COUPLE
HOURS AROUND SUNRISE. LEANING TOWARDS DRY TAFS FOR TOMORROW.  42
&&

.PREV DISCUSSION... /ISSUED 1048 AM CDT SAT JUN 15 2013/

DISCUSSION...

UPPER RIDGE HOLDING SWAY OVER THE AREA WITH VERY DRY AIR ALOFT.
MOISTURE POOLING OVER THE EASTERN CWA THIS MORNING TO THE WEST OF
THE STALLED FRONTAL BOUNDARY (THOUGH IT IS SO DIFFUSE IT IS
DIFFICULT TO PINPOINT.) GPS IPW AND ACARS SHOWS PW OF 1.7 TO 1.85"
IN PLAY MAINLY IN THE EASTERN AND SOUTHERN HALF OF THE AREA WITH
SOME DRIER AIR SPREADING IN FROM THE GULF. HARD TO ARGUE WITH
PREVIOUS FORECAST REASONING - MOIST/MESOSCALE DRIVEN/DAYTIME
HEATING. A FEW SHOWERS THIS MORNING FROM AROUND SARGENT UP
THROUGH KATY AND NORTH INTO WALKER/HOUSTON COUNTY. LOOKS LIKE LOW
NEAR DRT SHEARING OUT ON WATER VAPOR BUT STILL PROVIDING SOME LIFT
THOUGH IT IS STRUGGLING TO REACH SETX WITH RIDGING ALOFT SAGGING
DOWN OVER SETX/LA. RAIN CHANCES FOR THE AFTERNOON AND EVENING
HOURS LOOK TO BE ON TRACK TO JUST SLIGHTLY HIGH (A LITTLE GUN SHY
AFTER YESTERDAYS RAIN CHANCES BEING TOO HIGH IN THE
AFTERNOON)...BUT AT LEAST THE MOIST AXIS IS OVER THE EASTERN CWA
AND NOT MOVING INTO IT. WILL LEAVE AFTERNOON AND EVENING FORECAST
AS IS AND ONLY ADD SOME SHOWERS TO THE MORNING AND NUDGE UP TEMPS
A DEGREE OR TWO...MINOR TWEAKS IS ALL.
45

PREV DISCUSSION... /ISSUED 435 AM CDT SAT JUN 15 2013/

DISCUSSION...
BASED ON SFC DEWPOINTS...LINGERING BOUNDARY FROM OVERNIGHT
CONVECTION LOOKS TO BE SITUATED FROM ROUGHLY ANAHUAC TO
MADISONVILLE. THOUGH IT`LL PROBABLY WAFFLE ABOUT FOR MUCH OF THE
DAY...ANTICIPATE THIS TO BE ONE OF ABOUT 3 FACTORS IN SOME SCT
SHRA/TSTMS TODAY - PRIMARILLY LATE AFTN AND EVNG ONCE WE HEAT UP
AGAIN. THE OTHER 2 TRIGGERS WILL PROBABLY BE A COMBIINATION OF THE
SEABREEZE AS WELL AS UPPER LEVEL TROF EXPECTED TO LIFT OUT OF THE
BIG BEND AREA AND ACROSS N TX. EXPECT VAST MAJORITY OF PRECIP TO
BE MESO/MICROSCALE DRIVEN BASED ON BOUNDARY LOCATION(S) AND
HEATING BUT GENERALLY KEPT INHERITED POPS SHOWING NE PARTS OF THE
CWA HAVING THE BETTER CHANCES AGAIN. FCST SOUNDINGS STILL LOOK TO
SUPPORT SOME ISOLATED PULSE SEVERE STORMS AND WITH SLOW STORM
MOTIONS THE POTENTIAL FOR SOME DECENT DOWNPOURS. LESS COVERAGE
EXPECTED FURTHER SOUTH AS MODEL DATA AND GOES SOUNDER IMAGES
INDICATES LESS AVAILABLE MOISTURE.

UPPER FLOW TRENDS MOSTLY ZONAL OVER SE TX INTO EARLY WEEK WITH A
WEAK FLAT RIDGE SITUATED OFFSHORE ALONG WITH A SERIES OF RIPPLES
MOVING ACROSS N TX. A WEAK FRONTAL BOUNDARY MAY MOVE INTO N TX
EARLY IN THE WEEK PROVIDING A FOCUS FOR PRECIP THERE. BULK OF IT
LOOKS TO OCCUR WELL TO OUR NORTH BUT IT`LL BE WORTH WATCHING FOR
ANY BOUNDARIES PUSHED FURTHER SOUTH THAT MAY AFFECT NRN COUNTIES.

MEDIUM RANGE SOLNS SUGGEST BERMUDA HIGH PUSHES WESTWARD INTO
CNTL/WRN GULF AND A MID LEVEL RIDGE BUILDS INTO THE REGION FROM
MEXICO DURING THE 2ND HALF OF THE WORK WEEK. ORIENTATION &
STRENGTH OF BOTH DON`T APPEAR TO COMPLETELY RULE OUT SOME ISOLATED
DIURNALLY DRIVEN PRECIP HOWEVER.

MORE SIGNIFICANT FCST UNCERTAINTY EXISTS NEXT WEEKEND. ECMWF
BRINGS AN UPPER LEVEL TROF/WEAKNESS FROM THE YUCATAN UP INTO S TX
WHICH FAVORS HIGHER RAIN CHANCES. GFS HAS ALSO BEEN SHOWING THIS
FEATURE IN THE YUCATAN BUT KEEPS THE RIDGE STRONG ENOUGH OVER TX TO
SUPPRESS BEST MOISTURE ETC WELL SOUTH INTO MEXICO.  47

MARINE...
NO MAJOR CHANGES PLANNED FOR THE NEXT MARINE PACKAGE AS THE LIGHT TO
OCCASIONALLY MODERATE ONSHORE FLOW PERSISTS THESE NEXT SEVERAL DAYS.
THIS PATTERN WITH THE STRONG SFC HIGH TO OUR EAST IS NOT EXPECTED TO
CHANGE MUCH THROUGH THE FCST PERIOD. NO ADVISORIES/FLAGS ANTICIPATED
ATTM. 41

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      95  75  95  76  94 /  30  20  20   0  10
HOUSTON (IAH)              95  75  94  75  94 /  20  10  20   0  10
GALVESTON (GLS)            90  80  90  80  89 /  10  10   0   0  10

&&

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

$$

DISCUSSION...45
AVIATION/MARINE...42