Flash Flood Warning 8, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1021 PM CDT SAT OCT 8 2011

.UPDATE...
QUICK UPDATE FOR CURRENT RADAR TRENDS.

&&

.DISCUSSION...
MAIN AREA OF HEAVY RAIN HAS PULLED UP NEARLY STATIONARY EXTENDING
FROM BROWNWOOD TO BRADY TO JUNCTION...WITH BROWNWOOD HAVING PICKED
UP WELL IN EXCESS OF 2 INCHES IN JUST THE LAST 90 MINUTES.
INCREASING SOUTHEAST FLOW FEEDING INTO THE CONVECTIVE LINE SHOULD
CONTINUE TO MAINTAIN THE HEAVY RAINFALL WELL INTO THE OVERNIGHT HOURS.

TO THE WEST...IR SATELLITE SHOWING INCREASING ENHANCEMENT AS
ANOTHER SHORTWAVE ROUNDS THE BASE OF THE UPPER LOW. SHOWERS AND
STORMS INCREASING ACROSS WEST TEXAS...AND THIS LIFT SHOULD HEAD
TOWARDS WEST CENTRAL TEXAS LATER TONIGHT. THUS...POTENTIAL FOR
HEAVY RAINFALL WILL CONTINUE.

&&

.PREV DISCUSSION... /ISSUED 637 PM CDT SAT OCT 8 2011/

UPDATE...
SEE 00Z AVIATION DISCUSSION BELOW.

AVIATION...
A LARGE AREA OF RAIN AND EMBEDDED THUNDERSTORMS CONTINUES ACROSS
MUCH OF WEST CENTRAL TEXAS...STRETCHING ACROSS THE
KSOA...KSJT...AND KABI TERMINALS. GIVEN VERY LITTLE EASTWARD
MOVEMENT OF THE SYSTEM...THESE SHOWERS AND STORMS WILL CONTINUE
THROUGH THE OVERNIGHT HOURS. WILL SEE MVFR CIGS AND VSBYS FOR MUCH
OF THE PERIOD...DROPPING DOWN TO IFR AS THE HEAVIER THUNDERSTORMS
MOVE OVER THE INDIVIDUAL SITES.

FARTHER EAST...KBBD AND KJCT HAVE MISSED OUT ON MOST OF THE
CONVECTION SO FAR. HOWEVER...AS OUTFLOW AND OTHER BOUNDARIES
SPREAD EAST...EXPECT THE AREA OF SHOWERS AND STORMS TO EXPAND EAST
AS WELL. MAY TAKE A FEW HOURS FOR THIS TO OCCUR...BUT EXPECT
WIDESPREAD MVFR CIGS FOR THEM TO DEVELOP AFTER MIDNIGHT.

PREV DISCUSSION... /ISSUED 352 PM CDT SAT OCT 8 2011/

SHORT TERM...
FOCUS IN THE SHORT TERM WILL BE THE CONTINUED THREAT FOR HEAVY
RAINFALL ACROSS THE ENTIRE AREA THROUGH SUNDAY AS A POTENT UPPER
LEVEL TROUGH LIFTS NORTH ACROSS THE AREA THROUGH THE PERIOD.
VERY DIFFLUENT UPPER LEVEL FLOW WITHIN THE RIGHT ENTRANCE REGION OF
THE UPPER JET AND REDEVELOPMENT OF THE LOW LEVEL JET TONIGHT WILL
RESULT IN A CONTINUATION OF WIDESPREAD SHOWERS AND THUNDERSTORMS
ACROSS THE AREA OVERNIGHT. COULD SEE A FEW STRONG STORMS OVER
SOUTHERN ZONES THROUGH THE EVENING HOURS WHERE BETTER INSTABILITY
EXISTS BUT SEVERE THREAT WILL BE RATHER LOW. CATEGORICAL POPS WILL
CONTINUE OVERNIGHT WITH THE MENTION OF HEAVY RAINFALL.

FLOW ALOFT WILL BECOME LESS DIFFLUENT ON SUNDAY AS THE MAIN JET CORE
LIFTS NORTH OF THE AREA...BUT LIFT WITH THE PASSAGE OF THE UPPER
LEVEL TROUGH WILL RESULT IN ADDITIONAL HEAVY RAINFALL ACROSS THE
AREA ON SUNDAY. HEAVIEST RAINFALL WILL SHIFT ACROSS EASTERN ZONES BY
SUNDAY AFTERNOON WITH PRECIPITATION EXPECTED TO END LATE SUNDAY NIGHT
OR EARLY MONDAY.

AS FOR QPF AMOUNTS...THE NAM CONTINUES TO PRODUCE SIGNIFICANTLY
LOWER QPF AMOUNTS THAN THE GFS AND ECMWF. SO FAR STORM TOTAL QPF
IS INDICATING 2-2.5 INCHES ACROSS TAYLOR COUNTY...WITH THE HIGHEST
TOTALS OVER NOLAN COUNTY WHERE 2 TO 4 INCHES HAVE FALLEN.
SURROUNDING THESE MAXIMA...1 TO 2 INCHES HAVE FALLEN GENERALLY WEST
OF A SONORA TO ABILENE LINE. WHILE THE NAM APPEARS TOO LIGHT WITH
ITS AMOUNTS....THEN GFS SEEMS A BIT TOO HIGH. FOLLOWED CLOSE TO HPC
GUIDANCE QPF THROUGH THE SHORT TERM WITH AN ADDITIONAL 2 TO 4 INCHES
LIKELY WITH LOCALLY HIGHER AMOUNTS THROUGH SUNDAY. DUE TO THE HEAVY
RAINFALL POTENTIAL...THE FLASH FLOOD WATCH WILL REMAIN IN EFFECT
ACROSS THE CONCHO VALLEY...BIG COUNTRY AND WESTERN PORTIONS OF THE
HEARTLAND THROUGH SUNDAY AFTERNOON. EXPECT MILD TEMPERATURES THROUGH
THE PERIOD WITH LOWS TONIGHT IN THE 60S AND HIGHS ON SUNDAY ONLY IN
THE LOW TO MID 70S.

LONG TERM...
FOR SUNDAY NIGHT...NAM QUICKLY MOVES PRECIP EAST OF THE AREA WHILE
THE MAV AND 12Z ECMWF KEEPS SOME ACTIVITY OVER THE FORECAST AREA
OVERNIGHT SUNDAY AND THROUGH THE DAY ON MONDAY. ECMWF AND MAV HAVE
BASICALLY THE SAME RAINFALL FOOTPRINT WITH THE HEAVIER AMOUNTS
OVER THE EASTERN CWA AND WITH THE ECMWF SHOWING GREATER RAINFALL
TOTALS. WILL KEEP THE WESTERN CWA DRY DURING THE DAY ON MONDAY AS
PER THE NAM BUT WILL KEEP SOME RAINFALL OVER THE EASTERN CWA PER
THE ECMWF AND MAV. AS THE UPPER TROUGH DE-AMPLIFIES INTO THE
FIRST OF THE COMING WEEK...A SECONDARY UPPER TROUGH WILL PUSH A
WEAK COLD FRONT THROUGH THE AREA LATE WEDNESDAY. WILL GO WITH A
DRY FRONTAL PASSAGE PER THE DRY ECMWF FORECASTED SOUNDING.

AFTERNOON HIGHS WILL BE IN THE UPPER 70S ON MONDAY...WARMING INTO
THE MID TO UPPER 80S THROUGH WEDNESDAY. POST FRONTAL AFTERNOON
TEMPERATURES ON THURSDAY WILL BACK INTO THE LOWER 80S WITH A
GRADUAL WARMING BACK INTO THE MID 80S BY THE END OF THE
EXTENDED...AROUND 5 DEGREES WARMER THAN CLIMO. MORNING LOWS WILL
RANGE FROM THE MID 50S TO AROUND 60.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 	 63  72  55  75  60 / 100  80  30  10  10
SAN ANGELO 	 62  73  55  78  55 /  90  80  30  10  10
JUNCTION 	 65  76  61  81  58 / 100  80  60  30  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR THE FOLLOWING
ZONES: BROWN...CALLAHAN...COKE...COLEMAN...CONCHO...FISHER...
HASKELL...IRION...JONES...KIMBLE...MASON...MCCULLOCH...MENARD...
NOLAN...RUNNELS...SAN SABA...SHACKELFORD...STERLING...TAYLOR...
THROCKMORTON...TOM GREEN.

&&

07

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
409 PM CDT SAT OCT 8 2011

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-092115-
FISHER-NOLAN-STERLING-COKE-RUNNELS-IRION-TOM GREEN-CONCHO-
CROCKETT-SCHLEICHER-SUTTON-HASKELL-THROCKMORTON-JONES-SHACKELFORD-
TAYLOR-CALLAHAN-COLEMAN-BROWN-MCCULLOCH-SAN SABA-MENARD-KIMBLE-
MASON-
409 PM CDT SAT OCT 8 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

A FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE CONCHO VALLEY AND
BIG BIG...AS WELL AS THE WESTERN PORTION OF THE HEARTLAND THROUGH
SUNDAY. SHOWERS AND THUNDERSTORMS WITH HEAVY RAINFALL MAY RESULT
IN FLASH FLOODING OF ROADS...CREEKS AND STREAMS...LOW WATER
CROSSINGS...AND ESPECIALLY URBAN AREAS ACROSS THESE AREAS THIS
AFTERNOON AND AGAIN OVERNIGHT. THE GREATEST POTENTIAL FOR FLASH
FLOODING WILL EXIST NORTH OF A LINE FROM STERLING CITY TO
BALLINGER.

IN ADDITION...SOME THUNDERSTORMS MAY APPROACH SEVERE LEVELS ALONG
THE I-10 CORRIDOR THROUGH THIS EVENING...MAINLY SOUTH OF A IRAAN
TO MERTZON TO MASON LINE. THE MAIN HAZARDS WILL BE DAMAGING WIND
GUSTS AND DEADLY LIGHTNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

HEAVY RAINFALL WITH THE THREAT FOR FLASH FLOODING WILL CONTINUE
ACROSS THE AREA ON SUNDAY. THE GREATEST THREAT FOR FLASH FLOODING
WILL OCCUR ACROSS THE CONCHO VALLEY...BIG COUNTRY AND THE WESTERN
PORTION OF THE HEARTLAND WHERE A FLASH FLOOD WATCH WILL REMAIN IN
EFFECT THROUGH SUNDAY AFTERNOON. HEAVY RAINFALL MAY RESULT IN FLASH
FLOODING OF ROADS...CREEKS AND STREAMS...LOW WATER CROSSINGS...AND
ESPECIALLY URBAN AREAS ACROSS THESE AREAS ON SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN ANGELO TX
447 PM CDT SAT OCT 8 2011

TXZ076>078-082315-
CROCKETT TX-SCHLEICHER TX-SUTTON TX-
447 PM CDT SAT OCT 8 2011

...SIGNIFICANT WEATHER ADVISORY EFFECTIVE UNTIL 615 PM CDT FOR
CROCKETT...SCHLEICHER AND SUTTON COUNTIES...

AT 441 PM CDT...A CLUSTER OF STRONG THUNDERSTORMS WAS INDICATED BY
NATIONAL WEATHER SERVICE DOPPLER RADAR ACROSS SOUTHWESTERN SUTTON
AND SOUTHERN CROCKETT COUNTIES. THE STRONGEST STORM WAS LOCATED 20
MILES SOUTHWEST OF SONORA. THE STORMS WERE MOVING NORTH AT 30 MPH.

* THE STRONG THUNDERSTORMS WILL BE NEAR...
  OZONA BY 500 PM CDT
  I-10 NEAR THE CROCKETT-SUTTON COUNTY LINE AND THE INTERSECTION OF
  I-10 AND RANCH ROAD 1989 BY 515 PM CDT
  THE INTERSECTION OF US-190 AND RANCH ROAD 1828 AND US-190 NEAR THE
  CROCKETT-SUTTON COUNTY LINE BY 550 PM CDT

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE
INDOORS IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

PEA SIZE HAIL AND WIND GUSTS TO 45 MPH ARE LIKELY WITH THESE STORMS.
HEAVY RAINFALL WILL CAUSE PONDING OF WATER ON AREA ROADWAYS...
ESPECIALLY THOSE IN POOR DRAINAGE AREAS. RESIDENTS ARE ENCOURAGED TO
MONITOR THE SITUATION CLOSELY AND BE PREPARED TO TAKE THE PROPER
ACTIONS SHOULD A WARNING BE ISSUED.

LAT...LON 3107 10156 3104 10048 3032 10048 3032 10156
TIME...MOT...LOC 2144Z 188DEG 25KT 3043 10092