Flash Flood Warning 81, NWS Houston/Galveston, TX

000 
WGUS74 KHGX 220006
FFSHGX
TXC239-220015-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
605 PM CST SUN NOV 21 2004

...THE FLASH FLOOD WARNING FOR JACKSON COUNTY EXPIRED AT 600 PM
CST...

ALTHOUGH THE IMMEDIATE THREAT OF NEW FLOODING HAS PASSED... FLOOD 
WATERS FROM HEAVY RAINS EARLIER TODAY WILL BE SLOW TO RUN OFF. MANY 
AREAS MAY REMAIN INUNDATED FOR THE NEXT SEVERAL HOURS.

PLEASE REPORT FLOODING TO THE COUNTY SHERIFF...LOCAL POLICE...OR
DEPARTMENT OF PUBLIC SAFETY. THEY WILL RELAY YOUR REPORT TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 2907 9685 2888 9671 2909 9650 2922 9665

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
225 PM CST SUN NOV 21 2004

DISCUSSION...
A COMPLICATED FORECAST AGAIN ACROSS SOUTHEAST TEXAS. THE PERSISTENT
BOUNDARY WHICH HAS REMAINED NEARLY STATIONARY ALONG THE COAST SINCE
EARLY SATURDAY WILL PUSH SLOWLY NORTH OVERNIGHT. HAVE LEANED TOWARD
THE SLOWER GFS SOLUTION IN THE MOVEMENT OF THIS BOUNDARY. THE RAIN
COOLED AIR TO THE NORTH OF THE BOUNDARY SHOULD HELP REINFORCE THE
BOUNDARIES POSITION SO CONFIDENCE IS LOW THAT MUCH NORTHERN MOTION
CAN BE EXPECTED OVERNIGHT. PWS ARE FORECAST TO CONTINUE TO SLOWLY
CLIMB TO BETWEEN 1.7-1.8 INCHES BY 6Z. WITH THE BOUNDARY IN PLACE
AND A SERIES OF UPPER LEVEL DISTURBANCES EMBEDDED IN THE SOUTHWEST
UPPER FLOW...IT SEEMS REASONABLE TO KEEP THE HIGH POPS IN PLACE. THE
GROUND REMAINS SATURATED AND ANY ADDITIONAL HEAVY RAIN WILL CAUSE
FLOODING SO AS A PRECAUTION...WILL MAINTAIN THE FFA OVERNIGHT. THE
AXIS OF HEAVIEST RAIN SHOULD BEGIN TO SHIFT SLOWLY NORTH OVERNIGHT
AND AFFECT AREAS THAT HAVENT RECEIVED AS MUCH RAIN. SEE THE WELL
WRITTEN QPFERD FOR MORE DETAILS ON THE EXPECTED HEAVY RAIN.

AS OF 2 PM...IT APPEARS THAT THE WIDESPREAD CONVECTION AFFECTING
WHARTON AND JACKSON COUNTIES HAS BEGUN TO WEAKEN. IF THE GFS IS
CORRECT...THIS RESPITE FROM THE RAIN WILL END AROUND 06Z WITH
ADDITIONAL DEVELOPMENT BETWEEN 06 AND 09Z. AT 19Z...SFC ANALYSIS
REVEALS ANOTHER WEAK BOUNDARY OVER THE EXTREME NORTHERN PORTION OF
THE CWA. PERHAPS THIS IS THE GENESIS OF THE SECONDARY BOUNDARY WHICH
THE ETA DEVELOPS AND FOCUSES PRECIP DEVELOPMENT ON LATER TONIGHT. IF
THAT IS THE CASE...PERHAPS POPS OVER THE SOUTH ARE TOO HIGH. SUFFICE
TO SAY...WITH NUMEROUS MESO-SCALE INFLUENCES...CONFIDENCE IS LOW.

GFS FORECAST SOUNDINGS HAVE K INDICES IN THE MID/UPPER 30S AND TTS
AROUND 50. IT APPEARS THAT THE GFS IS SUFFERING CONVECTIVE FEEDBACK
FOR MONDAY NIGHT...YET IT STILL LOOKS LIKE WIDESPREAD PRECIP FOR MON
NIGHT OVER THE NORTHERN 2/3RD OF THE CWA. THE DEEPER MOISTURE/BOUNDARY
SHOULD BE PULLED NORTHWESTWARD AWAY FROM THE COAST AS THE WEST COAST
TROF DEEPENS. SPC HAS HAS THE AREA OUTLOOKED IN SLT RISK ON
MON...BUT WILL LET THE NEXT SHIFT EXAMINE THINGS BEFORE MENTIONING
SEVERE IN THE ZONES. WILL UPDATE THE HWO THIS EVENING AND ADDRESS
LATEST FLOODING/SEVERE CONCERNS.

ON TUESDAY...THIS PATTERN FINALLY COMES TO A CLOSE AS THE UPPER TROF
OUT WEST PUSHES NORTHEAST. A SURFACE COLD FRONT WILL CROSS THE AREA
TUESDAY BRINGING A SQUALL LINE ACROSS THE AREA LATE TUES MORNING
INTO THE AFTERNOON. DYNAMICS LOOK IMPRESSIVE AND A HIGH WIND EVENT
LOOKS POSSIBLE. ANYONE ELSE TIRED OF OUR LITTLE EL NINO?

THE REST OF THE WEEK LOOKS GREAT WITH DRIER AIR AND COOLER TEMPS. BY
THURSDAY...IT LOOKS LIKE WE WILL ALL HAVE REASON TO GIVE THANKS.

.MARINE...
PRESSURE GRADIENT IS EXPECTED TIGHTEN AS THE UPPER TROUGH APPROACHES
THE SOUTH CENTRAL U.S. THIS WEEK. EXPECT WINDS OVER THE GULF WILL
REMAIN IN THE 15 TO 20 KNOT RANGE FOR THE NEXT COUPLE OF DAYS.
OFFSHORE WIND WILL FOLLOW THE FRONT TUESDAY NIGHT/WEDNESDAY MORNING
AND SPEEDS MAY INCREASE TO MORE THAN 20 OR 25 KNOTS. SMALL CRAFT
ADVISORY CONDITIONS ARE LIKELY BY MID WEEK.

&&

.AVIATION...
PRECIPITATION AND CEILINGS WILL CONTINUE TO PLAY HAVOC WITH THE TAFS
FOR THE NEXT 24 HOURS. A LARGE CLEARING IN THE OVERCAST HAS
DEVELOPED OVER COLLEGE STATION. WITH AFTERNOON HEATING...ADDITIONAL
CLOUDS ARE LIKELY TO REDEVELOP OVER THERE A BIT LATER THIS
AFTERNOON. ALL THE OTHER AIRPORTS ARE DEALING WITH THE PRECIPITATION
AND SHOULD CONTINUE THROUGH THE AFTERNOON. THERE MAY BE A BRIEF
BREAK IN THE ACTIVITY LATER THIS AFTERNOON AND EVENING...BUT MORE
RAIN AND LOW CEILINGS ARE LIKELY AGAIN IN THE MORNING HOURS. 46

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH HGX CWA THROUGH 430 AM MONDAY.
SCEC HIGH ISLAND TO MATAGORDA SHIP CHANNEL 0-20 NM WATERS.
SCA  HIGH ISLAND TO MATAGORDA SHIP CHANNEL 20-60 NM WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 66 73 65 73 51 / 70 80 80 70 05
HOUSTON (IAH)         67 74 67 76 52 / 70 60 60 70 05
GALVESTON (GLS)       72 76 72 76 59 / 50 50 30 70 05

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
455 AM CST SUN NOV 21 2004

TXZ163-164-176>179-195>200-210>214-226-227-235>238-221200-
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-
455 AM CST SUN NOV 21 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST TEXAS.

...FLOOD WATCH IN EFFECT THROUGH 6 PM TODAY...

.DAY ONE...TODAY AND TONIGHT
A FLOOD WATCH IS IN EFFECT TODAY FOR ALL OF SOUTHEAST TEXAS. PLEASE
REFER TO THE LATEST FLOOD BULLETIN (FFAHGX) FOR DETAILS.

A WARM FRONT WILL SLOWLY MOVE NORTH ACROSS THE REGION. THE WARM
FRONT IN COMBINATION WITH PASSING UPPER LEVEL DISTURBANCES...WILL
RESULT IN WIDESPREAD SHOWERS AND THUNDERSTORMS. WITH THE SOIL
ALREADY SATURATED...ADDITIONAL HEAVY RAINFALL WILL EASILY RUNOFF
LEADING TO POSSIBLE FLOODING. THE FLOOD WATCH MAY BE EXTENDED
THROUGH TONIGHT UPON FURTHER ASSESSMENT OF THE WEATHER SITUATION.

ALONG WITH THE THREAT OF FLOODING...SOME THUNDERSTORMS MAY BECOME SEVERE
ESPECIALLY NEAR THE WARM FRONT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.
THROUGH TUESDAY...ADDITIONAL RAINFALL ACCUMULATIONS OF 1 TO 3
INCHES WITH ISOLATED TOTALS APPROACHING 5 INCHES WILL BE POSSIBLE.
WITH THE GROUND ACROSS MUCH OF SOUTHEAST TEXAS ALREADY SATURATED...
A CONTINUED FLOOD THREAT IS POSSIBLE. SEVERE THUNDERSTORMS MAY ALSO
DEVELOP ACROSS SOUTHEAST TEXAS AND THE ADJACENT COASTAL WATERS. THE
MAIN THREAT WILL PROBABLY BE STRONG DAMAGING WINDS AND ISOLATED
TORNADOES.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED TODAY AND POSSIBLY...TONIGHT.