Flash Flood Warning 48, NWS Austin/San Antonio, TX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1206 AM CDT SUN OCT 4 2009

.DISCUSSION...
SEE AVIATION SECTION BELOW.

&&

.AVIATION...
NO SIGNIFICANT CHANGES FROM PREVIOUS FORECAST THINKING WITH IFR
CONDITIONS EITHER FORECAST OR ALREADY PREVAILING AND FORECAST TO
CONTINUE INTO SUNDAY MORNING BEFORE IMPROVING. ALTHOUGH
THUNDERSTORMS ARE NOT EXPLICITLY FORECAST AT TERMINALS...ISOLATED
THUNDERSTORMS WILL BE IN THE AREA. MVFR CONDITIONS WILL PREVAIL
AREA-WIDE BY 15Z SUNDAY. CHANCES FOR SHOWERS AND THUNDERSTORMS
WILL CONTINUE INTO SUNDAY...WITH SHORT-LIVED IFR CONDITIONS
POSSIBLE WITH THE STRONGER STORMS.

&&

.PREV DISCUSSION... /ISSUED 945 PM CDT SAT OCT 3 2009/

UPDATE...
RAIN BECOMING MORE SCATTERED.

DISCUSSION...
SHOWERS OVER THE EASTERN HALF OF THE CWA IS BECOMING MORE
SCATTERED AS AREA OF RAINFALL MOVES OUT OF THE SOUTHEASTERN
COUNTIES. HAVE DECREASED POPS FOR THE REST OF THE EVENING AND
REMOVED THE MENTION OF HEAVY RAIN. HAVE ALSO ADJUSTED TEMPS AND
DEW POINTS TO ACCOUNT FOR HOURLY TRENDS. THE REMAINDER OF THE
FORECAST LOOKS GOOD.

PREV DISCUSSION... /ISSUED 630 PM CDT SAT OCT 3 2009/

AVIATION... A MIX OF PREVAILING VFR AND MVFR CONDITIONS WILL
DETERIORATE TO IFR TONIGHT AT I-35 TAF SITES WITH NUMEROUS SHOWERS
AND ISOLATED THUNDERSTORMS CONTINUING. AT KDRT...CONDITIONS WILL
DETERIORATE TO THE LOWER-END OF MVFR BUT ARE CURRENTLY NOT
EXPECTED TO DIP INTO IFR. IMPROVEMENT TO MVFR IS FORECAST AT I-35
TAF SITES BETWEEN 14-16Z SUNDAY ALTHOUGH CONVECTION WILL CONTINUE
AND MAY LIMIT VSBYS/CIGS TO IFR. THE LOW LEVEL FLOW WILL BECOME
SOUTHERLY LATE TONIGHT OR EARLY SUNDAY WHEN THE WARM FRONT PUSHES
THROUGH.

PREV DISCUSSION... /ISSUED 236 PM CDT SAT OCT 3 2009/

DISCUSSION...
THIS AFTERNOON ELEVATED SHOWERS AND EMBEDDED THUNDERSTORMS WERE
INCREASING IN AREAL COVERAGE ACROSS SOUTH CENTRAL TEXAS AS AN
IMPULSE IN THE SOUTHWEST FLOW ALOFT TRAVERSES TEXAS. THERE WILL
BE LOCALLY HEAVY RAINFALL THIS EVENING...HOWEVER THE SPEED OF
THE SHOWERS AND THUNDERSTORMS SHOULD LIMIT THE AMOUNT OF RAINFALL
THAT FALLS AT ANY ONE LOCATION. MINOR URBAN AND STREET FLOODING
IS POSSIBLE THIS EVENING...ESPECIALLY ACROSS THE AUSTIN AND SAN
ANTONIO METRO AREAS. PACIFIC MOISTURE FROM THE REMNANTS OF
OLAF WILL COMBINE WITH THE LOW LEVEL GULF MOISTURE TO PRODUCE
THE LOCALLY HEAVY RAINFALL THIS EVENING AND SUNDAY.

A WARM FRONT IS CURRENTLY LOCATED ACROSS DEEP SOUTH TEXAS. THIS
FEATURE WILL LIFT SLOWLY NORTHWARD OVERNIGHT. ORGANIZED CONVECTION
WILL OCCUR ALONG AND NORTH OF THIS BOUNDARY. THE WARM FRONT IS
EXPECTED TO BE NORTH OF OUR CWFA BY SUNDAY AFTERNOON. THUS THE
THREAT OF LOCALLY HEAVY RAINFALL WILL SHIFT TO OUR NORTHEAST
COUNTIES ON SUNDAY MORNING.

SOUTH CENTRAL TEXAS WILL BE IN A WARM AND HUMID AIRMASS ON MONDAY
WITH ANOTHER WEAK UPPER LEVEL IMPULSE TRAVERSING THE REGION.
HOWEVER LOW LEVEL CONVERGENCE WILL BE LACKING...THUS EXPECT
ONLY ISOLATED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ON
MONDAY.

RAIN CHANCES WILL BE ON THE INCREASE ON TUESDAY INTO WEDNESDAY AS
ANOTHER COLD FRONT MOVES INTO SOUTH CENTRAL TEXAS. THIS FRONT IS
LIKELY TO STALL ACROSS OUR REGION ON WEDNESDAY BEFORE RETURNING
NORTHWARD AS A WARM FRONT WEDNESDAY NIGHT.

A STRONGER COLD FRONT IS EXPECTED BY NEXT WEEKEND. THIS FRONT WILL
LIKELY REACH THE COAST BY NEXT SATURDAY NIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED WITH THIS FROPA MAINLY FRIDAY NIGHT
INTO SATURDAY. A DRIER AIRMASS WILL FINALLY OVERSPREAD SOUTH
CENTRAL TEXAS BY NEXT SUNDAY...GIVING SOUTH CENTRAL TEXAS A BREAK
FROM THE WARM AND HUMID WEATHER PATTERN.

&&

.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY              67  79  72  91  76 /  90  80  30  20  20
AUSTIN BERGSTROM INTL AIRPORT  68  80  72  91  75 /  90  80  30  20  20
NEW BRAUNFELS MUNI AIRPORT     69  84  72  91  75 /  90  70  30  20  20
BURNET MUNI AIRPORT            66  78  69  89  74 /  90  80  30  20  20
DEL RIO INTL AIRPORT           71  87  72  93  75 /  70  40  20  20  20
GEORGETOWN MUNI AIRPORT        67  79  71  90  74 /  90  80  30  20  20
HONDO MUNI AIRPORT             71  86  74  92  75 /  90  60  20  10  10
SAN MARCOS MUNI AIRPORT        69  82  76  91  75 /  90  70  30  20  20
LA GRANGE - FAYETTE REGIONAL   73  82  74  91  75 /  90  80  30  20  20
SAN ANTONIO INTL AIRPORT       71  83  75  91  77 /  90  70  20  20  20
STINSON MUNI AIRPORT           71  86  76  92  76 /  90  60  20  20  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

05/11

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
300 PM CDT SAT OCT 3 2009

TXZ171>173-183>194-202>209-217>225-228-041030-
LLANO-BURNET-WILLIAMSON-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-
GILLESPIE-KENDALL-BLANCO-HAYS-TRAVIS-BASTROP-LEE-KINNEY-UVALDE-
MEDINA-BEXAR-COMAL-GUADALUPE-CALDWELL-FAYETTE-MAVERICK-ZAVALA-
FRIO-ATASCOSA-WILSON-KARNES-GONZALES-DE WITT-LAVACA-DIMMIT-
300 PM CDT SAT OCT 3 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...TONIGHT...
AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS SOUTH CENTRAL TEXAS
TONIGHT. THIS FEATURE WILL COMBINE WITH DEEP ATMOSPHERIC MOISTURE
AND RESULT IN SHOWERS AND THUNDERSTORMS OVERNIGHT. MOST OF THE
RAINFALL WILL BE BENEFICIAL...HOWEVER THERE IS THE POTENTIAL FOR
LOCALLY HEAVY RAINFALL. RAINFALL AMOUNTS WILL GENERALLY BE ONE
HALF OF AN INCH TO ONE AND A HALF INCHES OVERNIGHT...WITH ISOLATED
HIGHER TOTALS OF TWO INCHES OR MORE POSSIBLE.

.DAY TWO...SUNDAY...
THE CHANCE FOR LOCALLY HEAVY RAINFALL WILL CONTINUE THROUGH MIDDAY
ON SUNDAY. THE THREAT OF HEAVY RAINFALL WILL END AS A WARM FRONT
MOVES NORTHWARD ACROSS SOUTH CENTRAL TEXAS. NEW RAINFALL AMOUNTS
ON SUNDAY WILL BE SIMILAR TO SATURDAY WITH WIDESPREAD TOTALS OF ONE
HALF OF AN INCH TO ONE INCH WITH ISOLATED HIGHER TOTALS OF TWO
INCHES.

.DAYS THREE THROUGH SEVEN...MONDAY THROUGH FRIDAY...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

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