Flash Flood Warning 18, NWS San Angelo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
140 PM CDT FRI MAY 30 1997

SLOW MOVING COLD FRONT IS STRUGGLING TO REACH THE ABILENE AREA AT
18Z AS WINDS THERE WERE LIGHT AND VARIABLE. ATMOSPHERE CONTINUES TO
DESTABILIZE AS ADAP LIFTED INDEXES RANGED FROM -8 TO -10 AND CAP
RANGED FROM ZERO IN THE EASTERN BIG COUNTRY TO BETWEEN 2 AND 4
DEGREES C OVER THE SOUTHWEST TWO THIRDS OF OUR REGION. SURFACE
MOISTURE CONVERGENCE HAS ALSO INCREASED WITH THE HIGHEST VALUES
AGAIN IN THE ABILENE AREA. CURRENTLY CONVECTION WAS LIMITED TO THE
RED RIVER FROM WICHITA FALLS TO SOUTHERN OKLAHOMA...BUT IT SHOULD
BEGIN TO SPREAD INTO OUR NORTHEAST COUNTIES SHORTLY GIVEN THE ABOVE
INSTABILITY/CAP/MOISTURE CONVERGENCE DATA...AS SEVERE STORM WATCH BOX
359 HAS JUST BEEN ISSUED FOR THOSE AREAS.

THE SEVERE WEATHER THREAT WILL CONTINUE THROUGH THIS EVENING ACROSS
THE REMAINDER OF WEST CENTRAL TEXAS SOUTH OF THE BIG COUNTRY...
ALTHOUGH WITH THE FRONT MOVING SO SLOWLY THE ACTIVITY MAY BE WEAKER
BY THE TIME IT REACHES THE SOUTHERN COUNTIES AFTER DARK. RAIN
CHANCES...HOWEVER...WILL BE HIGHER OVER OUR SOUTHEAST AREAS. THE
RAIN SHOULD BE OVER BY MIDNIGHT IN AREAS NORTH OF INTERSTATE 10 AND
THEN END OVER SOUTHERN AREAS BY EARLY MORNING. FWC GUIDANCE LOW
TEMPERATURES LOOK GOOD AS HIGHER DEW POINTS HOLDING ON TONIGHT WILL
MAKE AVN GUIDANCE LOWS UNREACHABLE EVEN WITH RAIN COOLED AIR.

FOR SATURDAY WINDS WILL BE LIGHT FROM THE EAST AND NORTHEAST...WHICH
WILL MAKE POST FRONTAL STRATOCUMULUS CLOUDS DIFFICULT TO SCOUR OUT
UNTIL THE AFTERNOON HOURS. LARGE SCALE SUBSIDENCE AND NORTHERLY FLOW
AT 500 MB WILL KEEP RAIN CHANCES AT ZERO. DUE TO THE CLOUDS AND WIND
DIRECTION...I WILL LOWER SATURDAY HIGH TEMPERATURES ABOUT A CATEGORY
FROM THE CURRENT FORECAST WHICH WOULD BE A NEAR SPLIT BETWEEN THE
GUIDANCE NUMBERS.

ABI 061/078 20
JCT 063/085 50
SJT 062/082 40

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TXZ049-053-054-064>066-071>073-076>078-113-114-127-128-139-140-
154-155-168>170-311100-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
221 PM CDT FRI MAY 30 1997

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

A COLD FRONT OVER NORTHWEST TEXAS WILL MOVE SLOWLY TO THE SOUTH
ACROSS WEST CENTRAL TEXAS LATE THIS AFTERNOON AND THIS EVENING. THE
ATMOSPHERE AHEAD OF THE FRONT IS MOIST AND VERY UNSTABLE. A LINE OF
THUNDERSTORMS IS EXPECTED TO DEVELOP AHEAD OF THE COLD FRONT IN
THE BIG COUNTRY BY MID AFTERNOON AND MOVE SOUTH ACROSS THE REMAINDER
OF WEST CENTRAL TEXAS DURING THE LATE AFTERNOON AND EVENING. DUE TO
THE INSTABILITY AND MAXIMUM DAYTIME HEATING IN PLACE AT TIME OF
FRONTAL PASSAGE...SOME STORMS WILL BE CAPABLE OF PRODUCING SEVERE
WEATHER WITH LARGE HAIL AND DAMAGING WINDS BEING THE MAIN THREATS.

AFTER MIDNIGHT THE THREAT FOR SEVERE WEATHER WILL DIMINISH AS MORE
STABLE AIR BEHIND THE COLD FRONT SPREADS SOUTHWARD ACROSS WEST
CENTRAL TEXAS.

SPOTTER ACTIVATION WILL LIKELY BE NEEDED.

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