Severe Thunderstorm Warning 152, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
259 PM CDT SUN OCT 22 2000

UPPER CLOSED LOW ENTERING BAJA CALIFORNIA IS PROGGED TO LIFT NORTH
ACROSS AZ AND INTO UT NEXT 48 HOURS...WITH THE SYSTEM OPENING INTO AN
UPPER TROUGH AND LIFTING NORTHEAST INTO THE PLAINS TUESDAY AND
TUESDAY NIGHT. AS THIS OCCURS...FRONTOGENESIS TO TAKE PLACE ALONG LEE
SIDE TROUGH TUESDAY WITH THE WEAK COLD FRONT MOVING INTO WEST CENTRAL
TX BY WEDNESDAY MORNING. MEANWHILE A DOWNSTREAM HIGH AMPLITUDE UPPER
RIDGE EXTENDING FROM GULF OF MEXICO NORTH INTO GREAT LAKES IS PROGGED
TO SHIFT A BIT WESTWARD OVER THE SHORT TERM...WITH HEIGHT RISES OVER
TX TONIGHT AND MONDAY. MODELS HOLD ONTO CONSIDERABLE MOISTURE OVER
WEST CENTRAL TX WITH A SE LOW LEVEL FLOW. BELIEVE MODELS OVERALL ARE
FAR OVERDONE WITH THE BROADBRUSH HIGH POPS AND QPF DUE TO THE DEEP
MOISTURE AND WEAK CAPPING OVER OUR REGION. THINK THE ETA MODEL LOOKS
MORE REALISTIC...EVEN THOUGH IT LOOKS OVERDONE OVER WESTERN TWO-
THIRDS OF OUR COUNTIES.

THE KSJT AND KDYX 88D RADARS SHOW WIDELY SCATTERED SHOWERS MOVING
NORTH ACROSS EASTERN THIRD OF CWFA THIS AFTERNOON. THESE ARE
DIURNALLY DRIVEN AND THINK THEY WILL DISSIPATE WITH LOSS OF HEATING.
WILL CARRY A 20-30 POP FOR TONIGHT.

ETA MODEL BRINGS A WEAK IMPULSE NORTH FROM SOUTH TX ACROSS OUR
EASTERN COUNTIES LATE MON AND MON NIGHT. ETA ALSO PROGS A NORTH TO
SOUTH WEAK THETA E RIDGE OVER OUR EASTERN COUNTIES...PRECIPITABLE
WATER VALUES OVER 1.5 INCHES...AND DECENT MOISTURE FLUX CONVERGENCE
LATE MON INTO TUESDAY. IF THIS MATERIALIZES...COULD SEE DECENT
RAINFALL IN OUR FAR EASTERN COUNTIES WITH POSSIBILITY OF LOCALIZED
EXCESSIVE RAINFALL. FOR MON WILL CARRY LIKELY AFTERNOON POPS NW HILL
COUNTRY...30-40 POP EASTERN COUNTIES AND 20 POP ELSEWHERE. MON NIGHT
WILL GO WITH LIKELY POP OVER FAR EASTERN COUNTIES WITH 20 POP FARTHER
WEST. AT THIS TIME FAVOR LOW POPS TUESDAY WITH LACK OF A SURFACE OR
UPPER FEATURE TO KEY ON...DESPITE ABUNDANT MOISTURE. WITH THE
APPROACH OF THE FRONT FROM THE WEST TUESDAY NIGHT/EARLY WEDNESDAY...
ENERGY IN THE BASE OF THE UPPER TROUGH WILL PROVIDE FAVORABLE DYNAMIC
SUPPORT FOR SHOWERS/THUNDERSTORMS AND A POSSIBLE SQUALL LINE.

BREAKS IN THE CLOUDCOVER HAVE OCCURRED TODAY...AND EXPECT THIS TREND
AGAIN MONDAY/TUESDAY. TEMPERATURES APPROACHING 80 WHERE BREAKS ARE
OCCURRING. GUIDANCE TEMPS LOOK A LITTLE TOO COOL WITH HIGHS AND WILL
LEAN TOWARD PERSISTENCE WITH THE GIVEN AIRMASS. EXPECT WIDESPREAD LOW
CLOUD DEVELOPMENT NEXT COUPLE OF NIGHTS.

IN THE EXTENDED...WEAK FRONT WEDNESDAY IS FOLLOWED BY STRONGER COLD
FRONT EARLY FRI AS UPPER TROUGH DIGS SOUTH INTO ROCKIES/PLAINS.

ABI 063/077/063/077 2263
SJT 063/078/063/078 2222
JCT 063/074/064/077 2673

.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>170-222300-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
239 PM CDT SUN OCT 22 2000

...SCATTERED SHOWERS AND NON SEVERE THUNDERSTORMS ARE EXPECTED
TONIGHT...

A MOIST AND SLIGHTLY UNSTABLE ATMOSPHERE WILL REMAIN OVER WEST
CENTRAL TEXAS TONIGHT. WEAK DISTURBANCES ALOFT WILL AID THE
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS TONIGHT...PRIMARILY EAST
OF A LINE FROM SONORA TO SAN ANGELO TO HASKELL. WITH LIMITED
ATMOSPHERIC INSTABILITY...SEVERE THUNDERSTORMS ARE NOT EXPECTED.

SPOTTER ACTIVATION IS NOT ANTICIPATED..

THIS OUTLOOK WILL RESUME SCHEDULED ISSUANCE ON MARCH 15 2000.
HOWEVER...THIS OUTLOOK WILL CONTINUE TO BE ISSUED AS NEEDED WHEN
THUNDERSTORMS THREATEN WEST CENTRAL TEXAS.

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