Wind Advisory 12, NWS Houston/Galveston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
329 AM CDT MON APR 25 2011

.DISCUSSION...

AS HAS BEEN THE CASE...SCT TSTMS PRESENT NW OF THE AREA OVER NORTH
CEN TX TONIGHT. SE TX REMAINS IN A WARM AND MOIST...BUT CAPPED AIRMASS
WITH MODERATE SOUTHERLY WINDS CONTINUING DURING THE OVERNIGHT HOURS.

THE MAIN FORECAST PROBLEM IS THE CHC OF TSTMS TODAY AND TONIGHT
AS A SHRT WV TROF APPROACHES AND MOVES ACROSS NORTHERN PORTIONS OF
THE AREA. MODEL GUIDANCE IS IN GENERAL AGREEMENT THAT WE WILL SEE SCT
TSTM DEVELOP ACROSS THE NORTHERN THIRD OF THE AREA BEGINNING LATE
THIS MORNING AND CONTINUING INTO THE EVE HOURS. NAM SHOWS DEVELOPMENT
A LITTLE FURTHER S DURING THE AFT HOURS AS COMPARED TO THE GFS. SIDED
WITH THE GFS. TIGHTENED THE POP GRADIENT TODAY WITH LITTLE IF ANY
ACTIVITY EXPECTED ACROSS THE COASTAL ZONES AND SOME CLUSTERING
OF STORMS POSSIBLE ACROSS THE N/NW AREAS. DURING THE AFT AND EVE HOURS
THE ATMOSPHERE WILL BE VERY UNSTABLE AND AGREE WITH THE SLIGHT RISK
FROM SPC FOR TODAY AND TONIGHT WITH THE MAIN THREATS BEING LARGE HAIL
AND STRONG WINDS. THE SEVERE TSTM THREAT IS EXPECTED TO BE ALONG AND
NORTH OF A BRENHAM TO CONROE TO LIVINGSTON LINE.

THERE IS A 2ND SHRT WV THAT PASSES A LITTLE FURTHER TO THE NORTH ON
TUE AND THERE COULD BE ISOLATED STRONG STORMS ACROSS THE NORTHERN HALF OF
THE AREA IN ASSOCIATION WITH THIS FEATURE. SO...I RETAINED THE SLIGHT
CHC POP FOR TUE. WITH NO UPPER LEVEL SUPPORT AM NOT CARRYING ANY MENTION
OF PRECIP ALONG THE COLD FRONT ON WED. HOWEVER...IT IS POSSIBLE THAT
THERE COULD BE A SHWR OR TWO ALONG THE BOUNDARY.

IT STILL LOOKS LIKE WE WILL MEET RED FLAG WARNING CRITERIA ON WED BEHIND
THE FRONT AS A VERY DRY AIRMASS MOVES INTO THE REGION WITH SUSTAINED W/NW
WINDS OF 15 TO 20 MPH.

FOR NEXT WEEKEND...EXPECT ANOTHER COLD FRONT TO MOVE INTO THE REGION ON
SUN. WILL CARRY A SLIGHT CHC POP FOR NOW AND ADJUST UPWARD IF NECESSARY
AS CONFIDENCE ON THIS FEATURE INCREASES. 33

&&

.MARINE...
PRESSURE GRADIENT WILL REMAIN SUFFICIENTLY TIGHT THROUGH TUESDAY
RESULTING IN A MODERATE TO STRONG ONSHORE FLOW. WE SHALL CONTINUE
WITH SCA FOR COASTAL WATERS AND BAYS TODAY BUT LIFTING BAYS THIS
EVENING...HAVING SCEC FOR THOSE AREAS. SEAS RUNNING 4 TO 7 FEET
COASTAL WATERS EARLY THIS MORNING. A COLD FRONT IS INDICATED TO PUSH
ACROSS THE COASTAL WATERS WEDNESDAY AFTERNOON AND WINDS SHOULD
PICK UP TO NEAR 20 KTS FROM THE NORTH COASTAL WATERS WEDNESDAY
NIGHT...BECOMING NORTHEAST THURSDAY AND WEAKENING. 37

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      91  73  92  69  85 /  40  20  20  10  10
HOUSTON (IAH)              87  74  89  73  88 /  20  10  10  10  10
GALVESTON (GLS)            84  74  84  75  85 /  10  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.

     SMALL CRAFT SHOULD EXERCISE CAUTION FROM THIS EVENING THROUGH
     TUESDAY MORNING FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY 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.

&&

DISCUSSION...33

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
505 AM CDT MON APR 25 2011

TXZ163-164-176>179-195>200-210>214-226-227-235>238-261100-
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-
505 AM CDT MON APR 25 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

...SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HALF OF
SOUTHEAST TEXAS THIS AFTERNOON AND EVENING...

.DAY ONE...TODAY AND TONIGHT

AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS NORTH TEXAS ALLOWING
FOR SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE
NORTHERN HALF OF SOUTHEAST TEXAS. STRONG INSTABILITY WILL SUPPORT
A SLIGHT RISK OF SEVERE THUNDERSTORMS...WITH LARGE HAIL AND
DAMAGING WINDS BEING THE PRIMARY THREAT DURING THE AFTERNOON AND
EVENING HOURS.

.DAY TWO...TUESDAY

NORTHEAST PORTIONS OF SOUTHEAST TEXAS COULD SEE ISOLATED STRONG
THUNDERSTORMS DEVELOP IN THE VICINITY OF A SECOND UPPER LEVEL
DISTURBANCE.

.DAY THREE...WEDNESDAY

MUCH DRIER AIR WILL MOVE INTO THE REGION ON WEDNESDAY IN THE WAKE
OF A FRONT. SUNNY SKIES...BRISK WINDS...AND RH VALUES IN THE 20S
WILL PRODUCE ELEVATED FIRE DANGER CONDITIONS ACROSS THE REGION.

.DAYS FOUR THROUGH SEVEN...THURSDAY THROUGH SUNDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE THIS AFTERNOON AND EVENING.