Tornado Warning 36, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
800 PM CDT THU MAY 15 2003

AFTER COORDINATION WITH SPC...ISSUED TORNADO WATCH WHICH COVERS MOST
OF WEST CENTRAL TEXAS THROUGH MIDNIGHT. SATELLITE AND WSR-88D
IMAGERY INDICATING STRONG TO SEVERE STORMS ARE RAPIDLY DEVELOPING TO
OUR WEST AND MOVING INTO OUR WESTERN ZONES. ENVIRONMENT IS RIPE FOR
TORNADOS WITH CAPES EXCEEDING 3000 J/KG AND IMPRESSIVE HELICITY.

.SJT...TORNADO WATCH UNTIL MIDNIGHT TONIGHT FOR THESE COUNTIES...

BROWN           CALLAHAN        COLEMAN
HASKELL         JONES           MCCULLOCH
SHACKELFORD     TAYLOR          THROCKMORTON
FISHER          NOLAN           SAN SABA
COKE            CONCHO          IRION
RUNNELS         STERLING        TOM GREEN

IN ADDITION...LAKE CAUTION BIG COUNTRY ZONES TONIGHT.

23/HUBER

****  221 PM CDT THU MAY 15 2003 DISCUSSION  ****

SIGNIFICANT SEVERE WEATHER THREAT FOR LATE THIS AFTERNOON AND
TONIGHT...ESPECIALLY ACROSS BIG COUNTRY. PLEASE REFER TO LATEST DAY
1 SPC OUTLOOK FOR DETAILS ON SEVERE DISCUSSION. MODERATE SEVERE RISK
DEPICTED IN THE OUTLOOK (ACROSS BIG COUNTRY) FROM I-20 NORTHWARD.
SOUTHERN EDGE OF HIGH RISK AREA SLIGHTLY TO THE NORTH OF
HASKELL/THROCKMORTON COUNTIES.

STILL A COMPLEX SCENARIO IN PINPOINTING THE TIMING AND PLACEMENT
OF THUNDERSTORMS. WARM FRONT LIFTING NORTH INTO BIG COUNTRY THIS
AFTERNOON. FRONT SHOULD BE LOCATED VICINITY OF NORTHERN BIG COUNTRY
OR NEAR RED RIVER BY LATE AFTERNOON. POSITION OF FRONT WILL
DETERMINE WHERE THUNDERSTORMS DEVELOP THIS EVENING. STORM
DEVELOPMENT OR MOVEMENT INTO BIG COUNTRY MAY HOLD OFF UNTIL LATE
THIS EVENING. DRYLINE NEAR THE TX/NM BORDER TO MIX EASTWARD THIS
AFTERNOON INTO WESTERN TX...STAYING WEST OF OUR COUNTIES. COMPACT
UPPER LOW TO TRACK ACROSS NORTHERN NM THIS AFTERNOON INTO TX
PANHANDLE TONIGHT...CONTINUING INTO CENTRAL OK FRIDAY. DRYLINE TO
BEGIN A WESTWARD RETREAT EARLY TONIGHT BEFORE WEAK PACIFIC FRONT
OVERTAKES IT AND MOVES EAST INTO WEST CENTRAL TX OVERNIGHT. AS UPPER
LOW APPROACHES...STRONG LIFT AND INSTABILITY ALONG WITH VERTICAL
SHEAR OVER BIG COUNTRY INDICATE POTENTIAL FOR SIGNIFICANT SEVERE
EVENT WITH ISOLATED TORNADOES...VERY LARGE HAIL AND DAMAGING WINDS.
STRONG CAP FARTHER SOUTH TO INHIBIT ANY STORM DEVELOPMENT THIS
AFTERNOON AND EARLY EVENING. STORMS ALSO EXPECTED TO DEVELOP LATE
AFTERNOON/EVENING ALONG NORTHERN PART OF DRYLINE TO THE NW OF OUR
COUNTIES. FOR TONIGHT... GIVEN THE AMOUNT OF INSTABILITY...
IMPRESSIVE LIFT...AND LOW LEVEL JET SETUP ALONG WITH THETA E
RIDGE...COULD SEE SOUTHWARD DEVELOPMENT AS PACIFIC FRONT OVERTAKES
DRYLINE. COULD HAVE SQUALL LINE MOVE ACROSS BIG COUNTRY...POSSIBLY
EXTENDING OR DEVELOPING FARTHER SOUTH. WILL CARRY THE GOING POPS AND
SEVERE WORDING IN NEXT SCHEDULED ZONE PACKAGE.

WILL RETAIN POPS IN OUR EASTERN COUNTIES FRIDAY. FRONT TO MOVE INTO
THAT AREA LATE MORNING OR EARLY AFTERNOON. DRY AND A LITTLE COOLER
SATURDAY AS UPPER LOW MOVES AWAY FROM OUR REGION. UPPER RIDGE TO
BUILD INTO SOUTHERN/CENTRAL PLAINS OVER WEEKEND INTO MONDAY BEFORE
FLATTENING TUESDAY. DRY WITH TEMPERATURES WARMING TO WELL ABOVE
NORMAL AGAIN DURING THIS TIME FRAME.

AN UPPER TROUGH IS PROGGED TO MOVE FROM NORTHERN PLAINS INTO UPPER
MIDWEST AND GREAT LAKES TUESDAY INTO WEDNESDAY. TRAILING PORTION OF
ASSOCIATED COLD FRONT PROGGED TO DROP SOUTH ACROSS WEST CENTRAL TX
BY TUESDAY. LATEST GFS IS STRONGER WITH THIS FRONT. GFS ALSO HAS
WEAK SHORTWAVES MOVING INTO REGION..SUGGESTS ISENTROPIC LIFT AND
GENERATES PRECIPITATION INTO NORTHERN HALF OF OUR COUNTIES TUESDAY
INTO WEDNESDAY. WILL LOWER TEMPERATURES MIDWEEK AND CARRY MORE CLOUD
COVER...BUT PREFER TO HOLD OFF POPS AND AWAIT ANOTHER MODEL RUN TO
CHECK FOR CONSISTENCY.

PRELIMINARY CCF
ABI 068/092/059/086/062 51000
SJT 071/095/060/088/062 30000
JCT 072/092/062/089/061 32000

.SJT...CAUTION ADVISED ON AREA LAKES BIG COUNTRY ZONES TONIGHT

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TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-140-
154-155-168>170-161930-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
230 PM CDT THU MAY 15 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL TEXAS.

.DAY ONE...

A MODERATE RISK OF SEVERE WEATHER IS EXPECTED ACROSS THE BIG
COUNTRY...WITH ONLY A SLIGHT RISK FOR THE REST OF THE AREA. THE
FURTHER NORTH THE BETTER THE CHANCE OF SEVERE WEATHER. VERY LARGE
HAIL...DAMAGING WINDS AND ISOLATED TORNADOES ARE EXPECTED WITH THESE
STORMS. EXPECT AN AREA OF STORMS TO DEVELOP ACROSS THE PANHANDLE TO
NEAR MIDLAND LATE THIS AFTERNOON BEFORE SLIDING EAST THROUGH THE BIG
COUNTRY THIS EVENING.

.DAYS TWO THROUGH SEVEN...

ISOLATED STORMS WILL CONTINUE TO LINGER INTO FRIDAY MORNING IN THE
EAST...WITH A FEW OF THOSE POSSIBLY SEVERE. OTHERWISE...NO OTHER
SEVERE WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY FOR THE BIG COUNTRY AND MAY BE
NECESSARY FOR THE REST OF WEST CENTRAL TEXAS TONIGHT.

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