Severe Thunderstorm Warning 70, NWS Houston/Galveston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
410 AM CDT FRI APR 20 2012

.DISCUSSION...
COLD FRONT WILL BE MAKING ITS WAY INTO THE NRN ZONES DURING THE
EARLY/MID AFTN HOURS AND BE SITUATED RIGHT ALONG THE COAST JUST
BEFORE SUNSET. ACTUAL COLDER/DRIER AIRMASS WILL PROBABLY LAG 3-6
HOURS BEHIND THE INITIAL WINDSHIFT. FSCT POPS AHEAD OF THE
BOUNDARY ARE PROBLEMATIC AND DON'T HAVE A WHOLE LOT OF FCST
CONFIDENCE. FCST SOUNDINGS AND OBSERVED AIRCRAFT SOUNDINGS SHOW A
MONSTER CAP OVER MOST OF THE AREA ALONG WITH RELATIVELY DRY AIR.
EARLIER THINKING WAS THAT CONVERGENCE ALONG THE BOUNDARY SHOULD BE
ENOUGH TO BUST THE CAP AND ALLOW THE INCREASING LLVL MOISTURE TO
BE TAPPED INTO IN ADDITION TO WHAT THE STORM SYSTEM WAS BRINGING
ALONG ITSELF. HOWEVER...LATEST MODEL RUNS AREN'T SHOWING NEARLY AS
IMPRESSIVE SFC CONVERGENCE...ESP IF THE PREFRONTAL TROF MOVES THRU
AS FAST AS SUGGESTED. THAT BEING SAID...UPPER DYNAMICS STILL
SUPPORT FAVORABLE CONDITIONS FOR SOME STRONGER TSTMS SHOULD ANY
DEVELOP WITH STEEP LAPSE RATES AND DIVERGENCE ASSOCIATED WITH THE
LFQ OF JET NOSING IN. GFS...NAM12...ECMWF...AND NCEP 4KM WRF ALL
SHOW WIDESPREAD PRECIP DEVELOPING AND WILL CONTINUE TO GIVE THEM
SOME RESPECT. HOWEVER...WITH WHAT IS CURRENTLY BEING OBSERVED I
TEND TO FAVOR THE OUTLYING TX TECH 3KM WRF WHICH SHOWS ONLY
PERIODIC THIN BANDS OF SCT SHRA/TSTMS ALONG THE WIND SHIFT ITSELF.
WENT AHEAD AND LOWERED POPS/QPF FROM WHAT WE HAD...BUT PROBABLY
NOT AS MUCH AS I'D REALLY LIKE TO DUE TO CONSIDERABLE UNCERTAINTY.
FRONT SHOULD CLEAR THE COAST IN THE EVENING HOURS WITH CLEARING
SKIES EXPECTED OVERNIGHT.

A STRING OF VERY NICE DAYS WILL BE ON TAP THIS WEEKEND AND EARLY
NEXT WEEK WITH HIGH PRES IN CONTROL. WILL PROBABLY SEE A REINFORCING
SHOT OF DRY AIR FILTER INTO THE AREA MONDAY. ONSHORE WINDS SHOULD
RESUME TOWARD MIDWEEK WITH A GRADUAL WARMING/MOISTENING TREND
PREVAILING DURING THE SECOND HALF OF THE WEEK. 47

&&

.MARINE...
BUOYS...CMAN...AND OIL RIG METAR SITES REPORTING WINDS FOR SCEC
CONDITIONS SO WILL CONTINUE SCEC THROUGH MID MORNING.  GUIDANCE
INDICATES WINDS WILL DIMINISH SLIGHTLY BY LATE MORNING.  NEXT ISSUE
IS COLD FRONT PASSING INTO WATERS LATE FRIDAY EVENING INTO SATURDAY
MORNING.  WILL OPT FOR SCA WITH WINDS 20-30KTS DEVELOPING AND WAVES
RISING TO 10FT IN OFFSHORE WATERS. WILL LET NEXT SHIFT EVALUATE
GALE WATCH/WARNING NEED BUT CONTINUE TO MENTION GALE FORCE WINDS
POSSIBLE PER COORDINATION WITH CRP AT TAFB.  QUICK SHOT OF WINDS AND
WAVES FRI/SAT SHOULD DIMINISH BY SUNDAY AS HIGH BUILDS IN.  04

&&

.AVIATION...
PESKY BKN V SCT030 DECKS ON SHORT BAND IR AROUND METRO AIRPORTS.
SATELLITE LOOP SHOWS MOTION OFF TO ENE SO MAY SEE BRIEF PERIODS OF
MVFR CIGS THIS MORNING.  COLD FRONT LOOKS TO BE PRECEDED BY
PRE-FRONTAL WIND SHIFT BY A COUPLE OF HOURS AS IT PASSES THROUGH
FROM THE NORTHWEST.  SO WILL VEER WINDS AROUND DURING THE DAY.
EXPECT A LINE OF QUICK MOVING SHRA/TSRA WITH FROPA...KCLL BY EARLY
TO MID AFTN AND AT METRO TERMINALS BETWEEN 21Z TO 01Z.  04

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      76  50  74  50  80 /  50  10   0   0   0
HOUSTON (IAH)              81  52  75  52  81 /  50  40   0   0   0
GALVESTON (GLS)            75  59  73  61  77 /  40  50   0   0   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM 1 AM TO 1 PM CDT SATURDAY FOR THE
     FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
     FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
     NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
     20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
     WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.

     SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 AM CDT THIS MORNING
     FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
     FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
     FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
     ISLAND TO FREEPORT OUT 20 NM.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
506 AM CDT FRI APR 20 2012

TXZ163-164-176>179-195>200-210>214-226-227-235>238-211015-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
506 AM CDT FRI APR 20 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

A COLD FRONT WILL MOVE INTO SOUTHEAST TEXAS THIS AFTERNOON AND
PUSH OFF THE COAST EARLY THIS EVENING. SCATTERED SHOWERS AND
THUNDERSTORMS MAY DEVELOP ALONG THE BOUNDARY. DUE TO A WARM LAYER
OF AIR ALOFT....CONDITIONS ARE NOT PARTICULARLY FAVORABLE FOR A
WIDESPREAD THREAT OF SEVERE WEATHER. HOWEVER...ISOLATED STRONG TO
SEVERE CELLS REMAIN A SLIGHT POSSIBILITY WITH HAIL AND DAMAGING
WINDS THE PRIMARY THREAT. ANYONE PLANNING OUTDOOR ACTIVITIES THIS
EVENING SHOULD PLAN FOR SOME WIND GUSTS TO 25 MPH IN THE WAKE OF
THE FRONT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON.

GMZ330-335-350-355-370-375-211015-
GALVESTON BAY-MATAGORDA BAY-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM-
WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM-
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM-
506 AM CDT FRI APR 20 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

A COLD FRONT IS FORECAST TO PUSH OFF THE COAST EARLY THIS
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG
THE BOUNDARY AND A FEW CELLS COULD BE STRONG TO SEVERE. WINDS WILL
SHIFT TO THE NORTH AND INCREASE TO 20 TO 30 KNOTS WITH SOME HIGHER
GUSTS IN THE WAKE OF THE FRONT. A SMALL CRAFT ADVISORY IS IN
EFFECT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

STRONG OFFSHORE WINDS WILL LIKELY CONTINUE THROUGH THE DAY
SATURDAY AND ADVISORIES WILL LIKELY CONTINUE FOR ELEVATED WINDS
AND SEAS. TIDES WILL ALSO FALL BELOW NORMAL. WINDS AND SEAS SHOULD
BEGIN LOWERING SATURDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION WILL NOT BE NEEDED.