Severe Thunderstorm Warning 265, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
830 PM CDT FRI OCT 18 2002

AFTER COORDINATION WITH SPC...DECIDED TO INCLUDE MOST OF WEST
CENTRAL TEXAS IN A SEVERE THUNDERSTORM WATCH. THIS WATCH WILL
CONTINUE UNTIL 1 AM TONIGHT. BEST UPPER DYNAMICS CURRENTLY PUSHING
ACROSS THE PERMIAN BASIN. IF CURRENT MOVEMENT CONTINUES...MAIN LINE
OF STORMS WILL MOVE INTO OUR WESTERN ZONES BY 10 PM THIS EVENING.
UPDATED ZONES TO INCLUDE SEVERE THUNDERSTORM WATCH AND INCREASE POPS
FOR THE CONCHO VALLEY TO CATEGORICAL. OTHERWISE...NO OTHER CHANGES.

.SJT...SEVERE THUNDERSTORM WATCH ALL ZONES EXCEPT BROWN AND SAN SABA
       UNTIL 1 AM.

23/HUBER

****  223 PM CDT FRI OCT 18 2002 DISCUSSION  ****

19Z ANALYSIS SHOWS AN UPPER LEVEL LOW OVER SOUTHWEST NEW
MEXICO...MOVING EAST. A SURFACE DRYLINE STRETCHED FROM ALONG THE
TEXAS PANHANDLE/NEW MEXICO BORDER...SOUTH TO THE DAVIS MOUNTAINS.
ALSO A COLD FRONT WAS PUSHING SOUTH INTO THE OKLAHOMA PANHANDLE.
AN AREA OF SHOWERS AND THUNDERSTORMS WAS SLOWLY LIFTING NORTHEAST
OUT OF WEST CENTRAL TEXAS...WITH ONLY ISOLATED SHOWERS REMAINING.
TEMPERATURES ARE IN THE 60S TO AROUND 70...WITH DEWPOINTS IN THE MID
60S.

TONIGHT...
THE ETA AND AVN INDICATE THE UPPER LEVEL LOW NEAR NEAR
LUBBOCK/CHILDRESS AREA BY 12Z. THIS WOULD SPEED UP THE TIMING OF THE
EASTWARD PROGRESSION OF THE DRY AIR...AND ALLOW THE DRYSLOT TO WORK
INTO WEST CENTRAL TEXAS SOONER. OTHERWISE...AS THE SLOW MOVING
SURFACE DRYLINE MOVES EAST ACROSS THE FORECAST AREA...A LINE OF
SHOWERS AND THUNDERSTORMS WILL DEVELOP AND PUSH EAST AHEAD OF IT.
EVEN THOUGH THE SURFACE DRYLINE IS SLOW TO CROSS THE AREA...THE
850MB WIND SHIFT IS MUCH SOONER...REACHING THE EASTERN EDGE OF THE
FORECAST AREA BY 12Z SATURDAY. THIS WILL HELP TO STRIP MUCH OF THE
MOISTURE BY SUNRISE SATURDAY.
LI/S DROP TO -4 AND A MODERATE THETA-E RIDGE BUILDS IN. ALSO THE
COLD AIR ALOFT SLIDES INTO THE REGION. HOWEVER EXTENSIVE CLOUD COVER
WILL LIMIT THE INSOLATION FOR LATE AFTERNOON BUILDUP OVER WEST
CENTRAL TEXAS. HOWEVER WITH BETTER INSOLATION OVER FAR WEST
TEXAS...IF A LINE OF STORMS DEVELOPS...IT COULD CARRY OVER INTO OUR
FORECAST AREA. THEREFORE THE SEVERE WEATHER POTENTIAL WILL CONTINUE
TO EXIST...WITH ISOLATED TO SCATTERED SEVERE STORMS POSSIBLE
TONIGHT. LARGE HAIL AND STRONG WINDS ARE THE MAIN CAUSE OF CONCERN.
WITH THE WIND SHEAR WOULD NOT RULE OUT A POSSIBLE TORNADO.

SATURDAY AND SATURDAY NIGHT...
LINGERING MORNING SHOWERS CAN BE EXPECTED IN THE SOUTHEAST. HOWEVER
DRY AIR WILL BUILD ACROSS ALL OF WEST CENTRAL TEXAS DURING THE
DAY...ALLOWING MOST IF NOT ALL AREAS TO SEE AT LEAST SOME AFTERNOON
SUN. AS THE COLD FRONT PUSHES INTO THE BIG COUNTRY DURING THE LATE
AFTERNOON...LOW LEVEL CLOUDS WITH A FEW LIGHT SHOWERS COULD POP UP
WITH THE MOISTURE WRAP AROUND SLIDING IN. THESE SHOWERS WILL NOT
AMOUNT TO MUCH OR LAST LONG...AS THE COOLER MOIST AIR BEHIND THE
FRONT MIXES WITH THE MUCH DRIER AIR ACROSS WEST CENTRAL TEXAS. BY
MID EVENING...SHOWERS WILL HAVE DISSIPATED IN THE BIG COUNTRY. AS
THE COLD FRONT PUSHES THROUGH THE CENTRAL AND SOUTHERN COUNTIES BY
MIDNIGHT...MIXING WILL HAVE PREVENTED ANY POSSIBLE SHOWERS FROM
DEVELOPING.

SUNDAY THROUGH FRIDAY...
SUNDAY AND MONDAY DRY COOL WEATHER WILL PREVAIL AS SURFACE HIGH
PRESSURE DOMINATES. BY TUESDAY...THE NEXT SHORT WAVE WILL HELP
TRIGGER OFF A FEW SHOWERS OR THUNDERSTORMS WITH MOISTURE BUILDING
BACK INTO WEST CENTRAL TEXAS. WEDNESDAY AND THURSDAY...MOISTURE
CONTINUES TO LINGER. HOWEVER THE BEST UPPER LEVEL SUPPORT HOLDS OFF
UNTIL FRIDAY...WHEN THE UPPER LEVEL JET PUSHES ACROSS THE REGION.
THEREFORE WILL HOLD OFF ON MENTIONING CHANCES WEDNESDAY AND THURSDAY
WITH A WEAK CHANCE...BUT WILL MENTION THE BETTER CHANCE FOR FRIDAY.
COOL WEATHER WILL CONTINUE THROUGH THE WEEK.

PRELIMINARY CCF...
ABI 060/076/048/068 8410
SJT 057/079/049/068 73-0
JCT 062/078/049/070 84-0

.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>170-182315-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
220 PM CDT FRI OCT 18 2002

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL TEXAS.

.DAY ONE...
THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS LATE THIS AFTERNOON
THROUGH TONIGHT ACROSS WEST CENTRAL TEXAS. THUNDERSTORMS ARE
EXPECTED TO DEVELOP ALONG A DRYLINE OVER FAR WEST TEXAS THIS
AFTERNOON...AND THEN MOVE EASTWARD ACROSS WEST CENTRAL TEXAS TONIGHT.
THE PRIMARY SEVERE WEATHER THREATS WILL BE LARGE HAIL AND DAMAGING
WINDS.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

.DAYS TWO THROUGH SEVEN...

A FEW LINGERING THUNDERSTORMS ARE POSSIBLE OVER FAR EASTERN SECTIONS
OF WEST CENTRAL TEXAS INTO SATURDAY MORNING. THERE IS A SLIGHT RISK
FOR A SEVERE STORM OR TWO SATURDAY...OVER FAR NORTHEASTERN PARTS OF
THE BIG COUNTRY...AND OVER EXTREME EASTERN SAN SABA COUNTY.

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