Severe Thunderstorm Warning 139, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
322 PM CDT SAT MAY 27 2000

THE 19Z SURFACE ANALYSIS PLACES THE WEAK COLD FRONT ALONG AN ALBANY TO
ROBERT LEE TO BIG LAKE LINE. THE BOUNDARY WAS SLOWING DOWN ACROSS
SOUTHERN COKE COUNTY. A LINE OF STRONG TO SEVERE THUNDERSTORMS WERE
DEVELOPING RAPIDLY ALONG THIS FRONT. EXPECT THIS LINE TO FILL IN AND
MOVE SLOWLY SOUTHEAST. THE ETA SHOWS THE BOUNDARY STALLING ALONG A SJT
TO BROWNWOOD LINE AROUND 06Z. THE CONVECTION MAY PUSH THE FRONT FARTHER
SOUTH... BUT EXPECT WIDESPREAD THUNDERSTORMS ALONG AND SOUTH OF THIS
FRONT INTO MIDNIGHT. THE THUNDERSTORMS WILL MOVE SOUTHEAST AT 10 MPH
EARLY THEN SOUTH OVERNIGHT. PRECIP WATER VALUES ARE AROUND 1.5 INCHES
AHEAD OF THE FRONT. THE SLOW MOVING STORMS COMBINED WITH CAPES UP TO
4000 J/KG SHOULD PRODUCE VERY HEAVY RAIN AND LARGE HAIL. PLAN TO ADDRESS
THIS IN THE ZONES AND GO WITH HIGH CHANCE TO LIKELY POPS ACROSS THE SE
1/2 OF OUR CWA TONIGHT. NORTH OF THE FRONT... THE THUNDERSTORM THREAT
HAS ENDED AND PLAN TO GO WITH LITTLE OR NO POPS THIS EVENING.

ON SUNDAY... THE FRONT IS EXPECTED TO WASH OUT. WITH HIGH PRESSURE
BUILDING IN FROM THE WEST ALOFT... LOOK FOR DRY AND HOT CONDITIONS TO
TAKE PLACE INTO MID WEEK WITH HIGHS NEAR OR ABOVE 100.

IN THE EXTENDED... THE UPPER HIGH IS FORECAST TO MOVE EAST OF THE REGION
AND ALLOW E TO SE FLOW TO DEVELOP. THIS IN TURN SHOULD COOL AFTERNOON
TEMPS DOWN INTO THE 90S.

PRELIMS:

ABI 067/093/069/102 -000
SJT 066/O94/070/104 5000
JCT 069/O91/069/099 6000

.SJT...NONE.

TEW
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TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-272300-

WEST CENTRAL TEXAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
127 PM CDT SAT MAY 27 2000

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING ACROSS MOST OF WEST CENTRAL TEXAS...

AT EARLY AFTERNOON...A WEAK COLD FRONT WAS IN THE BIG COUNTRY AND
NORTHWEST CONCHO VALLEY. THIS BOUNDARY EXTENDED FROM NEAR WICHITA
FALLS...TO NORTH OF ABILENE...TO STERLING CITY. THE ATMOSPHERE WAS
QUITE MOIST AND UNSTABLE SOUTH OF THE BOUNDARY WITH DEWPOINTS AROUND
70 DEGREES.

AS AN UPPER LEVEL TROUGH APPROACHES WEST TEXAS...THE BOUNDARY IS
EXPECTED TO MOVE SLOWLY SOUTHEAST...EXTENDING FROM OZONA...TO NEAR SAN
ANGELO...TO BALLINGER...TO CROSS PLAINS BY LATE AFTERNOON. STRONG LOW
LEVEL CONVERGENCE ALONG THE BOUNDARY...COMBINED WITH A VERY UNSTABLE
ATMOSPHERE AND ADEQUATE DIRECTIONAL WIND SHEAR WILL PRODUCE SCATTERED
THUNDERSTORMS THROUGH THIS EVENING.

THE SLIGHT RISK AREA IS GENERALLY EAST OF A LINE FROM SNYDER...
TO MERTZON...TO OZONA. SOME STORMS ACROSS THE SOUTHEAST HALF OF THE
BIG COUNTRY...THE CONCHO VALLEY AND HEARTLAND WILL LIKELY BECOME
SEVERE...PRODUCING LARGE HAIL...DAMAGING WINDS...AND LOCALLY HEAVY
RAINFALL SINCE STEERING WINDS ALOFT WILL BE LIGHT. LOCALIZED RAINFALL
AMOUNTS IN EXCESS OF TWO INCHES ARE POSSIBLE ALONG WITH ISOLATED
TORNADOES. STORM MOTION WILL BE TO THE SOUTHEAST AT 5 TO 15 MPH.

ACROSS THE NORTHERN EDWARDS PLATEAU AND NORTHWEST HILL COUNTRY...
THERE WILL BE A CHANCE OF THUNDERSTORMS PRIMARILY IN THE EVENING.
SEVERE THUNDERSTORMS ARE LESS LIKELY HERE.

SPOTTER ACTIVATION WILL LIKELY BE NEEDED..

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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