Flash Flood Warning 153, NWS Austin/San Antonio, TX

400 
WGUS74 KEWX 240913
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
413 AM CDT SAT OCT 24 2015

TXC029-091-187-259-241200-
/O.CON.KEWX.FF.W.0153.000000T0000Z-151024T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COMAL TX-BEXAR TX-GUADALUPE TX-KENDALL TX-
413 AM CDT SAT OCT 24 2015

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 AM CDT FOR
COMAL...BEXAR...SOUTHWESTERN GUADALUPE AND SOUTHEASTERN KENDALL
COUNTIES...

AT 408 AM CDT...GAUGE REPORTS OVER THE SAN ANTONIO METRO AREA
INDICATED 1 TO 2 INCHES OF RAINFALL HAD FALLEN OVER THE PAST TWO TO
THREE HOURS. SEVERAL ROAD CLOSURES HAVE BEEN REPORTED BY THE CITY OF
SAN ANTONIO. THUNDERSTORMS WITH HEAVY RAINFALL WILL CONTINUE TO
TRAIN OVER THE SAME AREAS OF SAN ANTONIO WITH ANOTHER 1 TO 3 INCHES
OF RAIN POSSIBLE. THROUGH 530 AM...THE HEAVIEST ADDITIONAL RAINS ARE
EXPECTED TO OCCUR OVER THE EASTERN HALF OF THE SAN ANTONIO METRO
AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

TURN AROUND...DONT DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 2918 9861 2972 9877 2990 9872 2993 9835
      2970 9793 2911 9841

$$

MO

390 
WGUS74 KEWX 241019
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
519 AM CDT SAT OCT 24 2015

TXC029-091-187-259-241200-
/O.CON.KEWX.FF.W.0153.000000T0000Z-151024T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COMAL TX-BEXAR TX-GUADALUPE TX-KENDALL TX-
519 AM CDT SAT OCT 24 2015

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 AM CDT FOR
COMAL...BEXAR...SOUTHWESTERN GUADALUPE AND SOUTHEASTERN KENDALL
COUNTIES...

AT 515 AM CDT...GAUGE REPORTS OVER THE SAN ANTONIO METRO AREA
INDICATED 1 TO 3 INCHES OF RAINFALL HAD FALLEN OVER THE PAST THREE
HOURS. SEVERAL ROAD CLOSURES HAVE BEEN REPORTED BY THE CITY OF SAN
ANTONIO. ANOTHER ROUND OF THUNDERSTORMS WITH HEAVY RAINFALL IS
CURRENTLY MOVING ACROSS THE SAME AREAS OF SAN ANTONIO WITH ANOTHER 1
TO 3 INCHES OF RAIN EXPECTED. THROUGH 7 AM...THE HEAVIEST RAINS ARE
EXPECTED TO MOVE TO THE NORTH ALONG THE HIGHWAY 281 CORRIDOR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

TURN AROUND...DONT DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 2918 9861 2972 9877 2990 9872 2993 9835
      2970 9793 2911 9841

$$

CP

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
101 AM CDT SAT OCT 24 2015

.AVIATION...
/06Z TAFS/
A COLD FRONT CURRENTLY ACROSS CENTRAL TEXAS WILL PUSH TO THE SOUTH
OVERNIGHT WHILE AN UPPER LEVEL TROUGH PUSHES TO THE SOUTHEAST FROM
THE FOUR CORNERS REGION. IN ADDITION...ABUNDANT TROPICAL MOISTURE
WILL PUSH TO THE NORTH FROM THE GULF OF MEXICO. ALL THESE
INGREDIENTS WILL COMBINE TO PRODUCE CLOUDY SKIES...SHOWERS AND
THUNDERSTORMS OVERNIGHT INTO SATURDAY AFTERNOON. MVFR CONDITIONS
ARE EXPECTED FOR THE NEXT FEW HOURS ACROSS AREA TERMINALS BEFORE
SHOWERS AND STORMS BEGIN TO AFFECT THE I-35 SITES. AS THE LINE OF
SHOWERS AND STORMS MOVE OVER THE TERMINALS OVERNIGHT AND EARLY
SATURDAY...EXPECT LOWER END IFR CIGS. CANT RULE OUT LIFR
CONDITIONS FOR SHORT PERIODS MAINLY DURING DAY BREAK. IFR
CONDITIONS WILL PREVAIL FOR MUCH OF SATURDAY. A WIND SHIFT IS
EXPECTED AROUND 22 TO 23Z TIME FRAME ALONG THE I-35 SITES AS THE
FRONTAL BOUNDARY PUSHES THROUGH. MODERATE NORTHERLY WINDS ARE
EXPECTED IN THE WAKE OF THE FRONT WITH WIND GUSTS UP TO 25 KNOTS.

&&

.PREV DISCUSSION... /ISSUED 1007 PM CDT FRI OCT 23 2015/

DISCUSSION...
MOISTURE CONTINUES TO INCREASE ACROSS SOUTH CENTRAL TEXAS THIS
EVENING WITH PWS NOW MOSTLY AT OR ABOVE 2 INCHES. UPWARD MOTION
ALSO INCREASING AS AN UPPER LEVEL TROUGH OVER ARIZONA APPROACHES.
SURFACE BOUNDARY FROM BROWNWOOD TO SONORA TO DRYDEN DRIFTING TO
THE SOUTH. MOISTURE CONVERGENCE ALONG THE BOUNDARY WILL CONTINUE
TO ALLOW FOR TRAINING OF SHOWERS AND THUNDERSTORMS THIS EVENING
THROUGH THE OVERNIGHT INTO MORNING AS IT SAGS SOUTH ACROSS THE
HILL COUNTRY TO ALONG THE ESCARPMENT. THIS IS THE GREATEST THREAT
AREA FOR HEAVY RAINS AND FLOODING INITIALLY. THE LOW LEVEL JET
STRENGTHENS OVERNIGHT FOR MORE WIDESPREAD STREAMER SHOWERS WITH
EMBEDDED ISOLATED THUNDERSTORMS MAINLY ALONG AND EAST OF HIGHWAY
281. AS THESE BECOME MORE PERSISTENT...HEAVY RAINS AND FLOODING
WILL BECOME A THREAT FOR THESE AREAS OVERNIGHT INTO MORNING. THE
BOUNDARY WILL CONTINUE TO SAG SOUTHEAST AS A SURFACE LOW BEGINS TO
TAKE SHAPE OVER FAR SOUTHERN TEXAS AS HURRICANE PATRICIA CONTINUES
TO MOVE NORTH ACROSS MEXICO. THE HEAVY RAIN AND FLOOD THREAT THEN
SLOWLY SHIFTS TO ALONG AND EAST OF HIGHWAY 281 DURING THE
AFTERNOON.

PREV DISCUSSION... /ISSUED 648 PM CDT FRI OCT 23 2015/

AVIATION...
WE ARE SEEING A BREAK IN THE ACTION AND ALL SITES ARE CURRENTLY
VFR. SHOWERS AND THUNDERSTORMS WILL REDEVELOP THIS EVENING AND
CONTINUE ON AND OFF THROUGH THE PERIOD. HAVE NOT TRIED TO GUESS
WHEN RAIN WILL STOP...BUT CIGS AND VIS WILL BE THE DRIVING FACTOR.
CIGS WILL GENERALLY BE LOWER THAN VIS AND WILL VARY BETWEEN MVFR
AND LIFR. A WIND SHIFT TO THE NORTH WILL COME SATURDAY EVENING.

PREV DISCUSSION... /ISSUED 458 PM CDT FRI OCT 23 2015/

SIGNIFICANT THREAT FOR FLASH AND RIVER FLOODING OVERNIGHT INTO SATURDAY
AS HEAVY RAIN AND THUNDERSTORMS IMPACT THE AREA...

SHORT TERM (TODAY THROUGH SATURDAY NIGHT)...

MAIN FOCUS REMAINS CENTERED AROUND THE DANGEROUS FLASH FLOODING AND
RIVER FLOODING RISK OVERNIGHT TONIGHT AND CONTINUING THROUGH
SATURDAY EVENING. RAINFALL AMOUNTS WILL BE GREATEST ACROSS THE
SOUTHEAST COASTAL PLAINS AS 6 TO 12 INCHES IS LIKELY WITH
ISOLATED POCKETS OF 15 INCHES POSSIBLE. A SECONDARY MAXIMUM WILL
BE LOCATED ACROSS THE HILL COUNTY AND NORTHERN PORTIONS OF THE
I-35 CORRIDOR WHERE 5 TO 8 INCHES ARE LIKELY WITH ISOLATED 10 INCH
POCKETS. THE MAIN TIME-FRAME FOR ENHANCED RAINFALL WILL BE FROM
LATE EVENING TONIGHT THROUGH 8-9PM SATURDAY. THESE AMOUNTS IN A
QUICK TIME FRAME WILL LEAD TO FLASH FLOODING AND QUICK RISES IN
LOCAL RIVERS AND CREEKS. THE MAIN RISK WITH THESE THUNDERSTORMS
WILL BE HEAVY RAIN AS THE HAIL AND TORNADO RISK WILL BE QUITE
LIMITED. THE CURRENT SYNOPTIC AND MESOSCALE SET-UP HISTORICALLY
FAVORS A HEAVY RAIN EVENT GIVEN +2 SD PWATS OF MOISTURE WITH DEEP
GULF AND TROPICAL PACIFIC AIRMASSES UNDERNEATH A MID TO UPPER
LEVEL LOW PRESSURE SYSTEM AND IN CONCERT WITH A DEVELOPING SURFACE
LOW ALONG THE TEXAS COAST DURING THE DAY SATURDAY.

CURRENTLY...SHOWERS AND THUNDERSTORMS ARE ONGOING ACROSS THE COASTAL
PLAINS ARCING NNW INTO THE AUSTIN AREA AND PORTIONS OF THE HILL
COUNTRY. THE COASTAL PLAINS NORTHWARD INTO BASTROP AND LEE COUNTIES
WILL BE THE FAVORED CORRIDOR OF NORTHWARD STREAMING SHOWERS THROUGH
THE NEXT 3 HOURS. AREAS WEST OF THIS LOCATION WILL SEE A LULL UNTIL
MID TO LATE EVENING WHEN ADDITIONAL DEVELOPMENT IS EXPECTED TO BOTH
MOVE FROM THE SOUTH AS WELL AS FROM THE NORTH IN THE HILL COUNTRY.

FOR OVERNIGHT INTO SATURDAY MORNING...SEVERAL WEATHER FACTORS WILL
COME TOGETHER TO DEVELOP HEAVY RAIN ACROSS THE REGION THAT WILL
INCREASE THE FLASH FLOODING RISK SUBSTANTIALLY. ENHANCED LIFT FROM
THE MID TO UPPER LEVEL LOW OVER NORTHERN MEXICO AND UPPER LEVEL
DIVERGENCE FROM 60-70 KT 300 MB FLOW WILL SUPPORT DEVELOPMENT OF
SHOWERS AND THUNDERSTORMS ACROSS A STALLED BOUNDARY OVER THE HILL
COUNTRY AND SOUTHERN EDWARDS PLATEAU. AT THE SAME TIME...A SURFACE
LOW IS EXPECTED TO DEVELOP ACROSS SOUTH TEXAS AND HELP SERVE AS A
LOW-LVL CONVERGENCE ZONE FOR NORTHWARD MOVING STORMS. THE HILL
COUNTRY ACTIVITY SHOULD BEGIN NEAR OT JUST AFTER MIDNIGHT AND THE
NORTHWARD MOVING ACTIVITY FROM THE SOUTH WILL LATE THIS EVENING
THROUGH THE OVERNIGHT. THESE STORMS WILL BE CAPABLE OF 2-3 INCH
PER HOUR RATES AND IF TRAINING OCCURS...AMOUNTS WILL ADD UP
QUICKLY AND FLASH FLOODING WILL RESULT DURING THE LOWER AWARENESS
PERIOD OF THE EARLY MORNING HOURS.

FOR MID-SATURDAY MORNING THROUGH SATURDAY NIGHT...THE COASTAL
SURFACE LOW WILL STRENGTHEN AND BECOME THE MAIN PRECIPITATION
DRIVER IN ASSOCIATION WITH THE FRONT. THE LOCATION AND PATH OF
THE SURFACE LOW WILL BE CRITICAL FOR ADDITIONAL RAINFALL AMOUNTS
DURING THIS PERIOD. THE ONCE STALLED FRONT OVER THE HILL COUNTRY
SHOULD SHIFT SOUTH SATURDAY WITH A NOTICEABLE 925MB TEMP GRADIENT
NOTED ACROSS THE REGION. WHERE THIS BAROCLINIC ZONE RESIDES WILL
BE THE MOST LIKELY LOCATION OF THE SURFACE LOW. THE SOUTHEAST
COASTAL PLAINS WILL BE THE MOST SUSCEPTIBLE TO RECEIVING HEAVY
RAIN DURING THIS TIME WHERE THE STRONG MID TO UPPER-LEVEL
DIVERGENCE WILL AID IN VERTICAL LIFT OF AMPLE LOW-LVL MOISTURE.
THE MERGING OF THE FRONT WITH THE COASTAL LOW WILL LIKELY CREATE
SOME LOCALIZED HIGHER RAIN INTENSITY BANDS THAT WILL ADD TO THE
OVERALL RAINFALL TOTALS. BY 4PM SATURDAY AFTERNOON THE HEAVY RAIN
SHOULD BE BEGIN TO MOVE OUT OF THE HILL COUNTRY AND ALL WESTERN
AREAS. BY 7PM...THE HEAVY RAIN RISK WILL SHIFT EAST OF THE METRO
AREAS. SOME LINGERING RAIN SHOWERS WILL PERSIST AS THE BASED OF
THE MID TO UPPER LOW TRAVERSE OVER THE REGION SATURDAY NIGHT INTO
SUNDAY MORNING.

LONG TERM (SUNDAY THROUGH NEXT FRIDAY)...

RESIDUAL LIGHT TO MODERATE RAIN AND STORMS WILL CONTINUE INTO MID-
DAY SUNDAY AS THE TROUGH AXIS PASSES OVER THE REGION AND THE STRONG
SURFACE LOW SHIFTS NEAR HOUSTON. WHILE LIGHTER AMOUNTS OF RAIN ARE
EXPECTED DURING THIS TIMEFRAME..ANY NEW AMOUNTS WILL FURTHER WORSEN
ANY ONGOING FLOODING CONCERNS.

MOST OF THE RAIN WILL END THROUGH SUNDAY AFTERNOON AND EVENING WITH
IMPROVING CONDITIONS. THE AREA WILL BE BEHIND THE FRONT WITH MUCH
COOLER READINGS AS HIGHS WILL BE IN THE UPPER 60S TO MID 70S ACROSS
THE REGION. A GRADUAL WARM UP WILL OCCUR TUESDAY AND WEDNESDAY BACK
INTO THE 70S AND 80S WITH DRY CONDITIONS EXPECTED. ANOTHER STRONG
FRONT ASSOCIATED WITH A SHARP TROUGH ACROSS THE CENTRAL PLAINS
SHOULD PASS THROUGH THE REGION LATE THURSDAY OR FRIDAY FOR OUR NEXT
ROUND OF RAIN.

&&

.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY              62  70  61  72  59 /  80  40  20  10  10
AUSTIN BERGSTROM INTL AIRPORT  61  71  59  72  58 /  90  40  20  10  10
NEW BRAUNFELS MUNI AIRPORT     63  73  60  74  58 /  80  30  20  10  10
BURNET MUNI AIRPORT            59  68  57  70  57 /  60  30  20  10  10
DEL RIO INTL AIRPORT           60  74  56  76  55 /  30  10  -   -    0
GEORGETOWN MUNI AIRPORT        60  70  58  71  57 /  80  40  20  10  10
HONDO MUNI AIRPORT             61  75  57  76  55 /  40  30  20  10  -
SAN MARCOS MUNI AIRPORT        63  71  60  73  59 /  90  30  20  10  10
LA GRANGE - FAYETTE REGIONAL   65  71  61  72  60 / 100  50  30  20  10
SAN ANTONIO INTL AIRPORT       63  74  60  74  59 /  70  30  20  10  10
STINSON MUNI AIRPORT           64  75  61  76  59 /  70  30  20  10  -

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BANDERA...BASTROP...BEXAR...BLANCO...BURNET...
CALDWELL...COMAL...DE WITT...DIMMIT...EDWARDS...FAYETTE...FRIO...
GILLESPIE...GONZALES...GUADALUPE...HAYS...KARNES...KENDALL...KERR...
KINNEY...LAVACA...LEE...LLANO...MAVERICK...MEDINA...REAL...TRAVIS...
UVALDE...VAL VERDE...WILLIAMSON...WILSON...ZAVALA.

&&

MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...04
PUBLIC SERVICE/DATA COLLECTION...33

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
553 PM CDT FRI OCT 23 2015

TXZ171>173-183>194-202>209-217>225-228-242300-
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-
553 PM CDT FRI OCT 23 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...TONIGHT.

A FLASH FLOOD WATCH REMAINS IN EFFECT TONIGHT FOR ALL OF SOUTH
CENTRAL TEXAS. AN UPPER DISTURBANCE INTERACTING WITH MOISTURE
FROM PACIFIC HURRICANE PATRICIA WILL PRODUCE A THREAT OF VERY
HEAVY RAINFALL OVER MUCH OF SOUTH CENTRAL TEXAS...ESPECIALLY LATE
THIS EVENING AND OVERNIGHT. MANY AREAS SHOULD SEE A POTENTIAL FOR
3 INCHES OR MORE OF RAIN THROUGH TONIGHT...LEADING TO FLASH
FLOODING. THE FLASH FLOOD POTENTIAL WILL INCREASE TONIGHT INTO
SATURDAY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

VERY HEAVY RAINS ARE EXPECTED SATURDAY THROUGH SATURDAY NIGHT...
ESPECIALLY OVER THE EASTERN TWO-THIRDS OF SOUTH CENTRAL TEXAS.
LARGE AREAS OF 5 TO 10 INCH RAINFALL AMOUNTS ARE EXPECTED TO
DEVELOP BY SUNDAY MORNING WITH A ISOLATED TOTALS OF 10 TO 15
INCHES POSSIBLE. ACROSS AREAS WEST OF A MOUNTAIN HOME TO PEARSALL
LINE...HEAVY RAINS SHOULD BE LESS WIDESPREAD. WESTERN COUNTIES
SHOULD EXPECT AREAS OF 1 TO 3 INCH RAINFALL AMOUNTS WITH ISOLATED
TOTALS UP TO 6 INCHES. THE TIMING FOR HEAVIEST RAINFALL IS
EXPECTED TO BE FROM EARLY SATURDAY MORNING THROUGH SATURDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE POSSIBLE SATURDAY.