Flash Flood Warning 7, NWS Fort Worth, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
340 PM CDT TUE APR 11 2000

SURFACE COLD FRONT PUNCHING THROUGH THE RED RIVER VALLEY AT PRESENT
WILL SLOWLY MOVE ACROSS THE REST OF THE REGION OVERNIGHT. STRONG
BAROCLINIC ZONE HAS DEVELOPED THIS AFTERNOON WITH CAPES AT OR ABOVE
2000 J/KG. AS THE BOUNDARY SAGS FURTHER SOUTH...STRONG THUNDERSTORMS
CAPABLE OF PRODUCING AREAS OF HEAVY RAINFALL WILL BE MONITORED
CLOSELY AS STEERING WINDS ALOFT REMAIN WEAK. THICKNESS SATURATION
BASED UPON PRECIPITABLE WATER VALUES IN EXCESS OF 1.25 INCH...
SUGGESTS HEAVIER DOWNPOURS WILL OCCUR MAINLY SOUTH AND EAST OF THE
METROPLEX. SEVERE THREAT WILL BE MAINLY HAIL AS THE WET BULB ZERO
REMAINS NEAR 10 THSD FEET AND LAPSE RATES ARE STEEP. WEAK VERTICAL
WIND SHEAR WILL LIMIT THE THREAT OF DAMAGING WINDS.

THE POTENTIAL FOR A PROLONGED RAINFALL EVENT WILL CONTINUE THROUGH
WEDNESDAY AS OVERRUNNING CONDITIONS AND A SERIES OF WEAK VORT LOBES
MOVE THROUGH THE REGION. WILL TEMPER POPS BEGINNING WEDNESDAY NIGHT
AS THE CLOSED LOW FILLS AND STARTS TO LIFT EASTWARD. AN EASTWARD
MOVING DRY LINE MAY PROVIDE THE FOCUS FOR ADDITIONAL CONVECTION OVER
THE EASTERN HALF ON THURSDAY WHERE MOISTURE WILL BE SLOW TO ERODE.
FWC GUIDANCE TEMPERATURES ACCEPTED WITH MINIMAL TWEAKING. EVENING
UPDATE WILL RECONSIDER THE NEED FOR A POSSIBLE FLASH FLOOD WATCH.
DRYING WILL OCCUR OVER MUCH OF THE WEEKEND EXCEPT FOR A CHANCE OF
RAIN OR THUNDERSTORMS DEVELOPING ALONG AN INVADING COLD FRONT ON
SUNDAY.

DFW 56/60/53/65 +733           ACT 61/66/57/66 +844

.FTW...NONE.                           ...48...

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-112300-

HAZARDOUS WEATHER OUTLOOK FOR NORTH TEXAS
NATIONAL WEATHER SERVICE FORT WORTH TX
1210 PM CDT TUE APR 11 2000

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS LATE THIS AFTERNOON
AND TONIGHT FOR A LARGE PART OF NORTH CENTRAL TEXAS. LARGE HAIL IS
THE PRIMARY THREAT. HOWEVER...HEAVY RAINFALL WITH AMOUNTS UP TO 2
INCHES ARE POSSIBLE MAINLY EAST AND SOUTH OF A BONHAM...CORSICANA...
TO GOLDTHWAITE LINE TONIGHT.

AT NOON...COOL AIR WAS POISED TO INVADE NORTH CENTRAL TEXAS BEHIND A
COLD FRONT EXTENDING FROM SOUTHERN OKLAHOMA TO WICHITA FALLS...
SAN ANGELO AND FORT STOCKTON. AS THE COLD FRONT MOVES ACROSS THE
REGION BY LATE TONIGHT...A SERIES OF UPPER LEVEL DISTURBANCES WILL
ARRIVE FROM A LOW PRESSURE CENTER MOVING INTO THE SOUTHERN ROCKIES.

COLD AIR ALOFT...DEEP MOISTURE...AND LIFT FROM THE APPROACHING
UPPER LEVEL STORM WILL RESULT IN A WIDESPREAD RAINFALL EVENT TONIGHT.
A FEW SEVERE THUNDERSTORMS WILL HAVE THE POTENTIAL FOR PRODUCING
LARGE HAIL. WEAK MID LEVEL WINDS AND THE SLOW MOVEMENT OF THE COLD
FRONT...WILL ALLOW FOR THE TRAINING OF SOME THUNDERSTORMS ALONG THE
INVADING COLD FRONT. THUS...THERE WILL BE A POTENTIAL FOR HEAVY
RAINFALL MAINLY SOUTH AND EAST OF THE DALLAS FORT WORTH METROPLEX
TONIGHT.

EMERGENCY MANAGEMENT AND STORM SPOTTER GROUPS ARE ADVISED TO
MONITOR THE LATEST WEATHER DEVELOPMENTS. ISOLATED SPOTTER ACTIVATION
MAY BE REQUIRED LATE THIS AFTERNOON OR EARLY EVENING ALONG THE RED
RIVER VALLEY AND WEST OF A MINERAL WELLS TO GOLDTHWAITE LINE.
ELSEWHERE...LIMITED SPOTTER ACTIVATION MAY BE REQUIRED AFTER 7 PM.

48

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-120000-

HAZARDOUS WEATHER OUTLOOK FOR NORTH TEXAS
NATIONAL WEATHER SERVICE FORT WORTH TX
344 PM CDT TUE APR 11 2000

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS THROUGH TONIGHT FOR A
LARGE PART OF NORTH TEXAS. LARGE HAIL IS THE PRIMARY THREAT.
HOWEVER...HEAVY RAINFALL WITH AMOUNTS UP TO 2 INCHES ARE POSSIBLE
MAINLY EAST AND SOUTH OF A BONHAM...CORSICANA...TO GOLDTHWAITE LINE.
TONIGHT.

COOLER AIR HAS BEGUN TO MOVE INTO NORTH TEXAS BEHIND A COLD FRONT
EXTENDING FROM NORTH OF DENTON TO NEAR SAN ANGELO. AS THE COLD FRONT
MOVES ACROSS THE REGION BY LATE TONIGHT...A SERIES OF UPPER LEVEL
DISTURBANCES WILL MOVE ACROSS THE REGION FROM A SURFACE LOW
PRESSURE CENTER IN THE SOUTHERN ROCKIES.  THUNDERSTORMS HAVE
DEVELOPED ALONG THE COLD FRONT AND ALONG A SURFACE LOW NEAR
STEPHENVILLE.

COLD AIR ALOFT...DEEP MOISTURE...AND LIFT FROM THE APPROACHING
UPPER LEVEL STORM WILL RESULT IN A WIDESPREAD RAINFALL EVENT TONIGHT.
A FEW SEVERE THUNDERSTORMS WILL HAVE THE POTENTIAL FOR PRODUCING
LARGE HAIL. WEAK MID LEVEL WINDS AND THE SLOW MOVEMENT OF THE COLD
FRONT...WILL ALLOW FOR THE TRAINING OF SOME THUNDERSTORMS ALONG THE
INVADING COLD FRONT. THUS...THERE WILL BE A POTENTIAL FOR HEAVY
RAINFALL MAINLY SOUTH AND EAST OF THE DALLAS FORT WORTH METROPLEX
TONIGHT.

EMERGENCY MANAGEMENT AND STORM SPOTTER GROUPS ARE ADVISED TO
MONITOR THE LATEST WEATHER DEVELOPMENTS. ISOLATED SPOTTER ACTIVATION
MAY BE REQUIRED LATE BY EARLY EVENING ALONG THE RED RIVER VALLEY AND
WEST OF A MINERAL WELLS TO GOLDTHWAITE LINE. ELSEWHERE...LIMITED
SPOTTER ACTIVATION MAY BE REQUIRED AFTER 7 PM.

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