Flash Flood Warning 14, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
309 AM CDT SUN SEP 9 2001

A DEEP UPPER LEVEL TROUGH IS DIGGING INTO THE PLAINS STATES. AT THE
SURFACE TWO COLD FRONTS ARE AFFECTING THE REGION. THE FIRST IS
STRETCHING FROM EASTERN OKLAHOMA...THROUGH WEST CENTRAL TEXAS JUST
SOUTH OF SAN ANGELO. THE SECOND STRONGER COLD FRONT IS FOLLOWING
RIGHT BEHIND THE FIRST...STRETCHING FROM CENTRAL OKLAHOMA THROUGH
WEST TEXAS...JUST MOVING INTO THE BIG COUNTRY. FORECAST CONCERNS OF
THE DAY INCLUDE WHERE PRECIPITATION WILL FORM AND HOW FAST AND FAR
THE FRONTS WILL MOVE THROUGH OR INTO THE SOUTHERN COUNTIES.

THE FIRST FRONT STRETCHING FROM EAST TO WEST ACROSS THE CENTRAL
COUNTIES...WILL SLOW DOWN AS IT PUSHES THROUGH THE SOUTHERN
COUNTIES. THIS WILL ALLOW THE SECOND FRONT TO EVENTUALLY CATCH UP TO
IT. THE SECOND FRONT STRETCHING FROM SOUTHWEST TO NORTHEAST WILL
MOVE SOUTHEAST THROUGH THE FORECAST AREA DURING THE DAY. AS THE
SECOND COLD FRONT GRADUALLY BECOMES MORE EAST TO WEST ACROSS THE
CENTRAL COUNTIES BY NOON...THIS WILL PROVIDE A FOCUS FOR MORE
SHOWERS WITH A FEW THUNDERSTORMS.

AS THE UPPER LEVEL TROUGH LIFTS TO THE NORTHEAST OVER THE NEXT
COUPLE OF DAYS...THIS WILL ALLOW WEAK HIGH PRESSURE TO GRADUALLY
BUILD OVER THE REGION. ON THE SURFACE BY THIS EVENING THE FRONT WILL
HAVE STALLED JUST TO THE SOUTHEAST OF THE FORECAST AREA. HOWEVER A
RETURN OF A SOUTHERLY MOIST FLOW DEVELOPS OVER THE SOUTHWEST
COUNTIES. WITH ISENTROPIC LIFT AND A WEAK THETA-E RIDGE
SUPPORTING...A FEW LIGHT SHOWERS COULD DEVELOP AFTER MIDNIGHT INTO
MONDAY MORNING THERE. HOWEVER WILL HOLD OFF ON MENTION OF SHOWERS
FOR NOW WITH SUCH A WEAK CHANCE. OTHERWISE...PARTLY TO MOSTLY CLOUDY
SKIES WILL CONTINUE THROUGH MONDAY NIGHT ACROSS THE SOUTH AND EAST
COUNTIES WITH MOSTLY CLEAR SKIES ACROSS THE BIG COUNTRY.

TUESDAY A WEAK UPPER LEVEL TROUGH WILL DEVELOP FROM EAST TO WEST
ACROSS THE SOUTHERN STATES INTO TEXAS. THE TROUGH WILL SLIDE SOUTH
THROUGH THURSDAY FINALLY PULLING OUT MUCH OF THE OF THE MOISTURE
LEFTOVER WITH THE SOUTHWEST COUNTIES TAKING THE LONGEST. OTHERWISE A
FLATTENED EAST TO WEST 500MB HIGH PRESSURE RIDGE WILL MAINTAIN DRY
CONDITIONS THROUGH SATURDAY.

PRELIMS...

ABI 076/057/083/060 2000
SJT 078/059/084/062 3--0
JCT 078/062/083/062 6--0

.SJT...NONE.

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TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-140-
154-155-168>170-091500-

WEST CENTRAL TEXAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
538 AM CDT SUN SEP 9 2001

...ISOLATED FLASH FLOODING IS POSSIBLE OVER SOUTHEAST PORTIONS OF
WEST CENTRAL TEXAS THIS MORNING...

A STRONG COLD FRONT EXTENDED ACROSS THE NORTHERN EDWARDS PLATEAU AND
NORTHWEST HILL COUNTRY EARLY THIS MORNING. SLOW MOVING THUNDERSTORMS
ALONG AND JUST NORTH OF THIS COLD FRONT WILL PRODUCE LOCALLY HEAVY
RAINFALL...WHICH MAY LEAD TO SMALL STREAM FLOODING AND ISOLATED
FLASH FLOODING. DUE TO MARGINAL INSTABILITY...SEVERE THUNDERSTORMS
ARE NOT EXPECTED.

THUNDERSTORM CHANCES WILL DECREASE BY MIDDAY...AS THE COOL AND
STABLE AIR FILTERS INTO ALL OF WEST CENTRAL TEXAS.

SPOTTER ACTIVATION IS NOT ANTICIPATED.

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.

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