Tornadoes and Flash Flood in Texas, September 8 to 9, 2001

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
254 PM CDT SAT SEP 8 2001

SPC PONDERING WATCH IN VICINITY OF STALLED FRONT ACROSS THE BIG
COUNTRY. CAPES IN EXCESS OF 4000 J/KG ACROSS THE EASTERN HALF OF
THE SJT CWFA. SAVING GRACE STRONG CAP. BUT CAP SOON TO ERODE AS
LARGE SCALE VERTICAL MOTION ASSOCIATED WITH POTENT SHORTWAVE
TROUGH ARRIVES. STAY TUNED.

WITH EXTREME INSTABILITY...COPIOUS MOISTURE AND FAVORABLE
DYNAMICS...OPTED FOR LIKELY OR CATEGORICAL POPS ACROSS MOST OF
THE CWFA. GOING TO MENTION POSSIBILITY OF LARGE HAIL...DAMAGING
WINDS AND LOCALLY HEAVY RAINFALL TONIGHT AS STRONG COLD FRONT
PLOWS SOUTHWARD.

LINGERING SHOWERS AND THUNDERSTORMS EXPECTED SUNDAY OVER THE
SOUTHERN HALF. GRADUAL CLEARING SUNDAY NIGHT AND MONDAY AS HIGH
PRESSURE BUILDS AT THE SURFACE. TUESDAY THROUGH SATURDAY BENIGN
WITH AMPLE SUNSHINE AND SEASONAL TEMPERATURES.

PRELIMS...

ABI 063/076/057/082 7000
SJT 065/075/059/085 6200
JCT 068/074/062/084 8400

.SJT...NONE.

17

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-140-
154-155-168>170-082330-

WEST CENTRAL TEXAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
205 PM CDT SAT SEP 8 2001

...A SLIGHT TO MODERATE RISK OF SEVERE THUNDERSTORMS EXISTS ACROSS
WEST CENTRAL TEXAS THIS AFTERNOON AND TONIGHT...

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON
AND MUCH OF TONIGHT ACROSS THE BIG COUNTRY...EASTERN CONCHO VALLEY
AND HEARTLAND. THE MODERATE RISK AREA IS TO THE RIGHT OF A LINE FROM
RICHLAND SPRINGS...TO MENARD...TO ROBY...TO SEYMOUR. THERE IS A
SLIGHT RISK OF SEVERE THUNDERSTORMS ELSEWHERE ACROSS WEST CENTRAL
TEXAS.

EARLY THIS AFTERNOON...A COLD FRONT EXTENDED FROM NEAR ARDMORE OKLAHOMA TO
JUST NORTH OF ABILENE. LOW LEVEL MOISTURE WAS PLENTIFUL ACROSS WEST
CENTRAL TEXAS WITH DEWPOINTS IN THE UPPER 60S AND LOWER 70S.

AS A WEATHER DISTURBANCE ACROSS COLORADO SWEEPS SOUTHEAST...
THE COLD FRONT WILL MOVE SLOWLY SOUTHWARD ACROSS THE BIG COUNTRY
LATE THIS AFTERNOON OR EARLY EVENING. THE COLD FRONT WILL THEN MOVE
SLOWLY SOUTH ACROSS THE REST OF WEST CENTRAL TEXAS OVERNIGHT.
SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP ALONG THE FRONT
LATE THIS AFTERNOON AND THIS EVENING DUE TO STRONG LOW LEVEL WIND
CONVERGENCE AND ADDED LIFT FROM THE APPROACHING WEATHER DISTURBANCE.

BECAUSE OF STRONG INSTABILITY AND WIND SHEAR...SOME OF THE STORMS WILL
LIKELY BECOME SEVERE LATE THIS AFTERNOON AND TONIGHT...WITH THE MAIN
THREATS BEING LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY
RAINFALL. ISOLATED TORNADOES WILL BE POSSIBLE...ESPECIALLY IN THE
MODERATE RISK AREA. THE SEVERE WEATHER THREAT WILL LIKELY DIMINISH
AFTER MIDNIGHT.

DURING THE LATE AFTERNOON AND EVENING...THUNDERSTORMS ALONG THE
FRONT WILL MOVE NORTHEAST AROUND 30 MPH.

SPOTTER ACTIVATION MAY BE REQUIRED FROM MID AFTERNOON...INTO THE
LATE EVENING HOURS.

FOR THE SOUTHWEST TEXAS AND SOUTHEAST NEW MEXICO OUTLOOK SEE PRODUCT
LBBSPSMAF. FOR THE SOUTH PLAINS OUTLOOK SEE PRODUCT LBBSPSLBB. FOR
THE CENTRAL OKLAHOMA OUTLOOK SEE PRODUCT OKCSPSOKC. FOR THE NORTH
TEXAS OUTLOOK SEE PRODUCT FTWSPSFTW. FOR THE SOUTH CENTRAL TEXAS
OUTLOOK SEE PRODUCT SATSPSSAT.

22/RUBIN