Severe Thunderstorm Warning 334, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE FORT WORTH TX
548 PM CDT FRI MAY 26 2000

OUTFLOW BOUNDARY FROM STORMS EARLY THIS MORNING WAS IN THE NORTHWEST
SECTION OF NORTH CENTRAL TEXAS THIS AFTERNOON. A DRYLINE WAS ALSO
LOCATED TO THE WEST OF THE REGION. THE AIRMASS WAS UNSTABLE THIS
AFTERNOON OVER MOST OF THE FORECAST AREA WITH ONLY A FEW DEGREES OF
WARMING NEEDED TO BREAK THE LOW LEVEL CAP. HOWEVER...THE AIRMASS
NORTH OF ABILENE WAS VERY UNSTABLE AND SHOULD BE THE AREA FOR THE
FIRST THUNDERSTORMS. THE STORMS WILL GENERALLY MOVE NE BUT A FEW OF
THE STORMS WILL MOVE IN A MORE EASTERLY MOTION. THE NORTHWEST HALF OF
THE FORECAST AREA HAS A CHANCE OF THUNDERSTORMS TONIGHT WITH THE
GREATEST RISK OF SEVERE WEATHER IN THE FAR NORTHWESTERN ZONE. THE
MODELS BRING A WEAK COLD FRONT INTO THE REGION LATE SATURDAY BRINGING
MORE THUNDERSTORMS. HOWEVER...THE OUTFLOW BOUNDARIES GENERATED BY
TONIGHT ACTIVITY WILL BE THE BIGGEST PLAYER IN WHERE THE
THUNDERSTORMS DEVELOP SATURDAY AND SUNDAY. CHANCE OF STORMS SHIFTS
TO THE SOUTHERN ZONES SUNDAY THEN RIDGING ALOFT HELPS THE CAP
STRENGTHEN AGAIN. WILL CONTINUE TO THE WARMER THAN NORMAL WEATHER
THROUGH WEDNESDAY OF NEXT WEEK.

.FTW...CAUTION ON AREA LAKES TONIGHT ALL BUT SE ZONES.

DFW 73/90/70/92 452           ACT 77/92/72/88 234

82

...AVIATION DISCUSSION...
MAIN QUESTION WILL BE TIMING OF THUNDERSTORMS ACROSS METRO AIRPORTS
TONIGHT. CURRENT TRENDS AND NE MEAN H85-H7 FLOW OF 230 DEGREES WILL
TRACK MOST STORMS NE. THAT COUPLED WITH A LINGERING CAP OVER NE AND E
TEXAS HINTS THAT STORMS MAY HOLD OF UNTIL CLOSER TO MIDNIGHT. BRUNT
OF ACTION WILL LIKELY BE CLOSER TO FRONTAL BOUNDARY THAT WILL HOLD UP
OVER OK TONIGHT. FRONT SLIDES SOUTH TOMORROW SO ANOTHER SHOT FOR
THUNDERSTORMS ALL AIRPORTS TOMORROW AFTERNOON. OTHERWISE SOME MVFR
CIGS BKN020 LATER TONIGHT. 80

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-270100-

HAZARDOUS WEATHER OUTLOOK FOR NORTH TEXAS
NATIONAL WEATHER SERVICE FORT WORTH TX
400 PM CDT FRI MAY 26 2000

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS NORTH AND WEST OF
A LAMPASAS...DALLAS...TO PARIS LINE FOR THIS EVENING AND TONIGHT.
THE SLIGHT RISK AREA INCLUDES THE CITIES OF LAMPASAS...BOWIE...
STEPHENVILLE...MINERAL WELLS...GAINESVILLE...SHERMAN...PARIS...AND
THE DALLAS FORT WORTH METROPLEX.

AN UPPER LEVEL DISTURBANCE MOVING INTO WEST TEXAS...WILL CONTINUE
TO TRIGGER THE DEVELOPMENT OF STRONG THUNDERSTORMS WEST OF A WICHITA
FALLS TO ABILENE LINE THIS EVENING. AS THESE THUNDERSTORMS MOVE
EAST...THEY MAY AFFECT AN AREA BETWEEN JACKSBORO AND EASTLAND BY
NIGHTFALL. ADDITIONAL THUNDERSTORMS MAY ALSO DEVELOP ALONG THE
REMNANTS OF AN OLD THUNDERSTORM BOUNDARY LOCATED ALONG A SHERMAN...
DENTON...TO EASTLAND LINE.

THE AIRMASS OVER NORTH TEXAS REMAINS QUITE UNSTABLE. HOWEVER...AN
EXTENSIVE SHIELD OF CLOUDS OVER THE REGION HAS LIMITED THE AMOUNT OF
SURFACE HEATING. IN ADDITION...A WARM LAYER OF AIR ALOFT CONTINUES TO
INHIBIT THUNDERSTORM DEVELOPMENT. AS COOLER AIR IN THE MIDDLE
LAYERS OF THE ATMOSPHERE ARRIVES TONIGHT...SCATTERED THUNDERSTORMS
WILL LIKELY DEVELOP TOWARD NIGHTFALL WEST OF A SHERMAN...DALLAS...TO
STEPHENVILLE LINE.

THE MAIN THREAT WILL BE LARGE HAIL AND DAMAGING WINDS. ISOLATED
SUPERCELL THUNDERSTORMS ARE MORE LIKELY WEST OF A GORMAN TO GRAHAM
LINE WHERE THE TURNING OF THE WIND WITH HEIGHT IS MORE FAVORABLE
FOR ROTATING THUNDERSTORMS.

EMERGENCY MANAGERS AND STORM SPOTTERS WEST A GAINESVILLE...TO
STEPHENVILLE LINE...COULD BE ACTIVATED BY 7 PM. ELSEWHERE...
ACTIVATION IS NOT EXPECTED UNTIL LATER TONIGHT.

FOR HAZARDOUS WEATHER/THUNDERSTORM OUTLOOKS FOR ADJACENT AREAS...SEE
OKCSPSOKC (NORTHWESTERN TEXAS...WESTERN AND CENTRAL OKLAHOMA)...
OKCSPSTUL (EASTERN OKLAHOMA AND NORTHWEST ARKANSAS)...NEWSPSSHV
(NORTHEAST TEXAS...NORTHWESTERN LOUISIANA...EXTREME SOUTHEASTERN
OKLAHOMA AND SOUTHWESTERN ARKANSAS)...SATSPSHOU (SOUTHEAST TEXAS)...
SATSPSSAT (SOUTH CENTRAL TEXAS)...AND LBBSPSSJT (WEST CENTRAL
TEXAS).