Tornado Warning 57, NWS Houston/Galveston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
526 AM CST MON NOV 22 2004

DISCUSSION...
BROAD BAND OF SHOWERS AND THUNDERSTORMS DEVELOP AROUND MIDNIGHT
FROM NEAR COT TO ACT AND HAS BEEN SHIFTING EAST (THOUGH THE NORTH END
OF THE LINE HAS BEEN MOVING FASTER.) LOOKS AS THOUGH A WIDESPREAD
RAINFALL TO OCCUR THIS MORNING ALONG AND NORTH OF THE I-10 CORRIDOR.
HEAVIER AMOUNTS WILL PROBABLY RUN FROM NEAR LA GRANGE TO PRAIRIE
VIEW TO CONROE AND PERHAPS LIVINGSTON. RAINFALL RATES OF 1.5 TO 2
INCH PER HOUR ARE TO BE EXPECTED AGAIN TODAY...HEAVIER AMOUNTS IN THE
SLOWER MOVING STORMS. COULD SEE THE BAND OF SHOWERS BECOME QUASI-
STATIONARY ALONG THE LA GRANGE-CONROE LINE BETWEEN 6 AND 9 AM. HIGH
PW...GPS IPWV 1.5 TO 1.7 OVER THE REGION ON LL FLOW OF 20 TO 30
KNOTS UP AND OVER THE STATIONARY FRONTAL BOUNDARY COT-PSX-GLS-SRST2.
EXPANSIVE CLOUD COVER AND PRECIP OVER THE AREA SHOULD HINDER
TEMPERATURE RISE TODAY. JET COMING ACROSS MEXICO THIS MORNING
FORECAST TO STRENGTHEN AND EVENTUALLY WE GET INTO A WEAKLY
COUPLED JET STRUCTURE THIS AFTERNOON OVER MAINLY THE EASTERN
PORTIONS OF SETX...THOUGH THIS DISTINCTION MAY BE INSIGNIFICANT GIVEN
THE BOUNDARY AND THE ELEVATED NATURE OF MOST OF THE STORMS. THE
MODELS HAVE BEEN HAVING A LOT OF TROUBLE WITH FORECASTING QUICK
MOVEMENT NORTH THE BOUNDARY EACH DAY SINCE FRIDAY...WHICH FOR THE MOST
PART HAS NOT OCCURRED. DO EXPECT TO SEE IT MOVE BACK NORTH TUESDAY AS
THE UPPER LOW OVER CA MOVES EAST TO AROUND EL PASO BY 15Z THEN EAST-
NORTHEASTWARD. THIS SHOULD GET THE BOUNDARY MOVING. VERY IMPRESSIVE
UPPER JET ROARING ACROSS MEX/TX TUESDAY (130-135 KNOTS) THAT WILL HAVE
US IN ITS SIGHTS. LFQ MOVES OVER THE AREA COINCIDENT WITH THE PACIFIC
FRONTAL PASSAGE. DRY PUNCH...LI -1 TO -4 AND STRONGER LLJ AND
HELICITIES IN THE 100-140 RANGE COULD WELL SUPPORT SEVERE THREAT. SPC
EVEN HAS THE EASTERN HALF OF THE AREA IN A MODERATE RISK. FRONT SWEEPS
OUT THE MOISTURE AND THEN REINFORCING CANADIAN AIRMASS DROPS IN
WEDNESDAY MORNING/AFTERNOON. SHOULD BE A GREAT TURKEY DAY WITH HIGHS
ONLY IN THE 59 TO 64 DEGREE RANGE AND A LITTLE BREEZE.

WILL CONTINUE THE FLOOD WATCH THROUGH 6 PM...AND AM PRETTY CERTAIN
THAT IT WILL BE EXTENDED THROUGH TUESDAY BY FOLLOWING SHIFTS. LOCALLY
HEAVY RAIN THREAT THROUGH TUESDAY. HAVE MENTION OF SEVERE IN THE
TUESDAY FORECAST AS WELL.

OUT OVER THE WATER THE WINDS HAVE BEEN BELOW SCEC WILL PROBABLY SEE
THE WINDS START TO COME UP TONIGHT AND MAY BEGIN HOISTING FLAGS.
SCEC AND SCA WILL LIKELY BE BACK IN THE PACKAGE EARLY TUESDAY
MORNING.

AS FOR THE TERMINALS...WILL BE PLAGUED WITH FOG-LIFR IMPROVING
14ZISH...BUT 4 TO 6 MILE FOG MAY REMAIN INTO THE AFTERNOON...
IMPROVING FOG VISBY MAY BE OFFSET BY PRECIP. SHRA/TSRA THIS MORNING
WILL BE SPREAD ACROSS THE NORTHERN PORTIONS OF THE REGION AND MAY
EXPAND SOUTH INTO IAH/HOU TERMINALS BUT TIMING IT DIFFICULT AND
CONFIDENCE ON TIMING LOW.

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH HGX CWA THROUGH 6 PM.
DENSE FOG ADVISORY HGX CWA THROUGH 9 AM.

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 70 65 72 52 59 / 100 100 80 20 00
HOUSTON (IAH)         74 67 76 54 62 / 100  90 80 40 00
GALVESTON (GLS)       77 71 77 60 64 /  70  60 70 50 00

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
717 AM CST MON NOV 22 2004

TXZ163-164-176>179-195>200-210>214-226-227-235>238-230600-
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-
717 AM CST MON NOV 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST TEXAS.

.DAY ONE...TODAY.
...A FLOOD WATCH IN EFFECT UNTIL 6 PM...
A STATIONARY FRONT ALONG THE COAST MAY WAFFLE AROUND TODAY WITH
DEWPOINTS IN THE MID 60S TO AROUND 70 FLOWING INTO AND OVER THE
FRONTAL BOUNDARY. VERY HEAVY RAINFALL WILL BE POSSIBLE TODAY AS
STORMS DEVELOP AND MOVE NORTHEAST OF THE FRONTAL BOUNDARY.
SOME MAY TRACK OVER THE SAME AREA AS OTHER STORMS LEADING TO GREATER
ACCUMULATIONS. RAINFALL ACCUMULATIONS OF AROUND 1 INCH SHOULD BE
COMMONPLACE NORTH OF THE INTERSTATE 10 CORRIDOR...ISOLATED TOTALS OF 6
TO 8 INCHES MAY BE POSSIBLE.

WITH THE WARM AND NEARLY SATURATED AIRMASS ACROSS THE AREA A LITTLE
HEATING TODAY COULD QUICKLY INCREASE THE INSTABILITY OF THE
ATMOSPHERE. ISOLATED STRONG TO SEVERE THUNDERSTORMS COULD BE POSSIBLE
IF TEMPERATURES RISE ABOVE 75 DEGREES...OR IF THE STATIONARY FRONT
DRIFTS NORTH AND THUNDERSTORMS DEVELOP TO THE SOUTH OF THE FRONTAL
BOUNDARY...BRIEF TORNADOES COULD BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...
ON TUESDAY...A COLD FRONT WILL SWEEP THROUGH THE AREA DURING THE
AFTERNOON COLLIDING WITH ABUNDANT GULF MOISTURE AS A POWERFUL UPPER
LEVEL DISTURBANCE ALONG WITH STRONGER SOUTHERLY WINDS COINCIDE
WITH THE FRONTAL PASSAGE. A MODERATE RISK OF SEVERE THUNDERSTORMS WILL
EXIST FOR MUCH OF THE DAY. THE PRIMARY THREAT WILL BE TORNADOES BUT
SOME THREAT OF DAMAGING WINDS AND HAIL WILL EXIST AS WELL. THE THREAT
OF TORNADOES WILL BEGIN AROUND 4 AM NEAR THE COAST AND WILL EXPAND
NORTH THROUGH THE HOUSTON METRO AREA BY 9 AM...AND MAY REACH AREAS AS
FAR NORTH AS HUNTSVILLE AND LIVINGSTON BY LATE MORNING. IN ADDITION...
HEAVY RAIN WILL ALSO ACCOMPANY THE STORMS AND MAY LEAD TO MORE
FLOODING. RAINFALL ACCUMULATIONS OF 2 TO 4 INCHES MAY BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED TODAY AND WILL LIKELY BE
REQUIRED ON TUESDAY.