Tornado Warning 7, NWS San Angelo, TX

WEST CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1055 AM CDT WED APR 23 2003

DRYLINE ON A FAST TRACK ACROSS THE PANHANDLE...SLIGHTLY SLOWER TO
THE SOUTH.  CU AND A FEW SHOWERS STARTING TO DEVELOP AHEAD OF
DRYLINE JUST TO THE NW OF OUR COUNTY WARNING AREA...STRONG S SURFACE
WINDS...GOOD DEW POINTS...AND UPPER LEVEL SUPPORT ALL INDICATE A
POTENTIAL FOR STORMS.

SPEED OF DRYLINE THROUGH AREA WILL BE THE DETERMINING FACTOR AS
DRYLINE BECOMES ORIENTED NE-SW.  BEST DYNAMICS OVER BIG
COUNTRY...BUT CANT RULE OUT STORMS FURTHER SOUTH AS MORNING CLEARING
ALLOWS TEMPS TO RISE INTO THE LOWER 80S.

THIS IS THE MAKE OR BREAK PRECIP MAKER FOR THE MONTH...BY AFTERNOON
ITLL ALL BE TO OUR EAST.

235 AM CDT WED APR 23 2003

SEVERE WEATHER EXPECTED OVER PORTIONS OF WC TX TODAY...WITH CLEAR
SKIES AND SEASONAL TEMPS THEREAFTER.

GOES WATER VAPOR IMAGERY SHOWS A POTENT NEUTRALLY-TILTED UPPER LEVEL
TROF CENTRAL AZ EARLY THIS MORNING. UPPER FLOW HAD BECOME DIFFLUENT
IN THE LEE OF THE NM MOUNTAINS. A FEW STORMS HAD FORMED NORTH OF
CLOVIS NM...AND WERE MOVING NNE. 07Z SURFACE ANALYSIS SHOWED A
DRYLINE BACKED UP AGAINST THE MOUNTAINS OF NM. ESE SURFACE
WINDS...EXTENSIVE LOW CLOUDINESS AND DEWPOINTS IN THE UPPER
50S/LOWER 60S PREVAILED OVER WC TX.

AFOREMENTIONED UPPER TROF WILL TAKE A NEGATIVE TILT AS IT LIFTS TO
NE NM BY MIDDAY. STRONG WESTERLY MID LEVEL JET ROUNDING THE BASE OF
THE UPPER TROF WILL HELP PUSH THE DRYLINE OFF THE MOUNTAINS THIS
MORNING...AND INTO WC TX THIS AFTERNOON. MESOETA APPEARS TO RESOLVE
DRYLINE MOVEMENT FAIRLY WELL...UNLIKE AVN...WHICH MIXES THE SURFACE
DRYLINE EAST TOO QUICKLY. AFTER A FEW STORMS FORM IN THE TRANS
PECOS/PERMIAN BASIN EARLY THIS AFTERNOON...EXPECT A SQUALL-LINE TO
EVOLVE AND MOVE EAST THROUGH WC TX. EXACT TIMING AND LOCATION OF
SQUALL LINE DEVELOPMENT UNCERTAIN...BUT BEST CHANCES FOR RAIN AND
SEVERE WEATHER WILL BE OVER NORTHERN AND EASTERN PORTIONS OF THE
FORECAST AREA...WHERE BEST LOW LEVEL CONVERGENCE WILL COINCIDE WITH
HIGHEST SURFACE BASED INSTABILITY DURING THE AFTERNOON. WILL
HIGHLIGHT THE POSSIBILITY OF SEVERE STORMS IN THE FORECAST. FOR
ADDITIONAL INFO REGARDING SEVERE WEATHER THREAT TODAY...SEE THE
LATEST DAY 1 CONVECTIVE OUTLOOK FROM THE SPC.

THUNDERSTORMS MAY PERSIST INTO THE EARLY PART OF THE TONIGHT PERIOD
OVER THE HEARTLAND AND PERHAPS EASTERN BIG COUNTRY. THEREAFTER...
DRIER AND MUCH MORE STABLE AIR FILTERS INTO WC TX. A WEAK BACK DOOR
COLD FRONT MAY SHAVE A FEW DEGREES OFF OF HIGH TEMPS OVER THE BIG
COUNTRY ON FRIDAY. OTHERWISE...PERSISTENCE APPEARS THE BEST FORECAST
THROUGH THIS WEEKEND...AS WC TX REMAINS UNDER WEAK RIDGING ALOFT. NO
SIGNIFICANT CHANGES PLANNED FOR THE EXTENDED.

PRELIM CCF...
ABI 080/054/085/050/081 4100
SJT 082/054/084/052/084 3000
JCT 078/052/083/050/084 3100

.SJT...NONE.

14

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-140-
154-155-168>170-241045-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
544 AM CDT WED APR 23 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL TEXAS.

.DAY ONE...

THERE IS A MODERATE RISK FOR SEVERE THUNDERSTORMS ACROSS THE EASTERN
PORTION OF THE BIG COUNTRY AND ALL OF THE HEARTLAND COUNTIES TODAY.
THIS MODERATE RISK AREA IS NORTH AND EAST OF A LINE FROM ASPERMONT
TO JUST WEST OF ABILENE AND BALLINGER TO BRADY AND SAN SABA.
ELSEWHERE THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TO THE EAST
OF A LINE FROM ROTAN TO ROBERT LEE...SAN ANGELO...ELDORADO AND
SONORA. THE DRYLINE WILL MOVE THROUGH THE AREA TODAY. THIS IN
COMBINATION WITH A STRONG UPPER LEVEL STORM SYSTEM WILL CAUSE
SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE SEVERE...ESPECIALLY
IN THE MODERATE RISK AREA. THE MAIN THREAT WILL BE VERY LARGE HAIL
AND DAMAGING WINDS. THERE WILL BE SUFFICIENT SHEAR FOR THUNDERSTORMS
TO PRODUCE TORNADOES...ESPECIALLY OVER THE MODERATE RISK AREA.
INTERESTED PERSONS WILL WANT TO PAY ATTENTION TO LATER FORECAST
CONCERNING THIS THUNDERSTORM EVENT.

.DAYS TWO THROUGH SEVEN...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED LATE THIS MORNING INTO THE AFTERNOON.

27/BRAZZELL