Severe Thunderstorm Warning 397, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
547 PM CDT SAT OCT 28 2000

AVIATION DISCUSSION...
MAIN AVIATION CONCERN WILL BE THE TIMING AND INTENSITY OF
THUNDERSTORMS.  EXPECT SCATTERED SHOWERS AND THUNDERSTORMS WEST OF
THE AREA TO INCREASE IN COVERAGE THROUGH 700 PM.  SOME OF THESE
STORMS WILL AFFECT THE METROPLEX AND WACO AFTER 700 PM...THEREFORE
WILL INCLUDE A TEMPO GROUP BETWEEN 00 AND 03Z.  BY 03Z THE STRONGER
STORMS WILL APPROACH FROM THE WEST AND MAY CONTAIN SOME GUSTY WINDS
AND HEAVY RAIN.  WILL KEEP THUNDER IN A TEMPO GROUP AND CALL FOR
PREVAILING RAIN BETWEEN 03 AND 07Z.  RAIN CHANCES SHOULD LOWER
THROUGH THE NIGHT AS SQUALL LINES WEAKENS.  WILL END RAIN CHANCES
AROUND 14Z WITH A SLOW LIFT IN THE CEILINGS THEREAFTER.  WINDS WILL
REMAIN FROM THE SOUTH TO SOUTHEAST BETWEEN 10 AND 15KTS UNTIL LATE
MORNING WHEN THEY TURN MORE SOUTHWESTERLY.

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300 PM PUBLIC DISCUSSION
THE STRONG UPPER LEVEL LOW OVER AZ./N.M. KICKING OUT RAPIDLY TO
THE NORTHEAST TONIGHT IS OUR MAIN CONCERN WITH THIS FORECAST. SEVERAL
WATCH BOXES ALREADY OUT AND MORE WILL COME OVERNIGHT...WHICH WILL BE
A LONG ONE FOR SOME OF US.  WE WILL ISSUE A FLASH FLOOD WATCH FOR ALL
BUT THE EXTREME EASTERN PART OF NORTH TEXAS FOR TONIGHT...GENERALLY
WEST OF A LINE FROM BONHAM...TO CORSICANA...TO CAMERON. OUR REASONS
ARE THREE-FOLD.

FIRST...AFTER OVER A WEEK OF INTERMITTENT RAIN...SOME PARTS OF THE
WATCH AREA HAVE HAD SIGNIFICANT RAINS AND WILL NOT BE ABLE TO
TOLERATE HEAVY RAINS OVER A SHORT PERIOD OF TIME. TWO...THE SPEED OF
THE STORMS WILL INITIALLY BE HIGH...BUT WILL SLOW LATER TONIGHT AS
THE LOW MOVES NORTHEAST.  THIRD...WHILE OUR CONFIDENCE IN FLASH
FLOODING IN THE EASTERN PART OF THE WATCH AREA IS NOT EXTREMELY
HIGH...OUR CONCERNS FOR FLOODING IN METROPOLITAN AREAS ON A
SATURDAY NIGHT WARRANTS THE EASTWARD EXTENSION.

WILL GO ABOVE POPS TONIGHT BUT WILL NOT STRAY MUCH FROM TEMPS.

DFW  66/77/58/80  +311
ACT  66/79/62/81  +522

.FTW...FLASH FLOOD WATCH TONIGHT WEST OF A BONHAM...CORSICANA...
       CAMERON LINE

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TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-291000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
429 PM CDT SAT OCT 28 2000

THERE IS A MODERATE RISK OF SEVERE WEATHER OVER THE EXTREME NORTHWEST
PART OF NORTH TEXAS TONIGHT...GENERALLY ALONG AND WEST OF A
GRAHAM...TO BRECKENRIDGE...TO CISCO LINE.

IN ADDITION...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT
ALONG AND WEST OF A BONHAM...ENNIS...LAMPASAS LINE.  THIS INCLUDES
THE DALLAS/FORT WORTH METROPLEX AS WELL AS SHERMAN...GAINESVILLE...
HILLSBORO...STEPHENVILLE...JACKSBORO...AND COMANCHE.

A VIGOROUS UPPER LEVEL STORM SYSTEM OVER WEST TEXAS WAS PRODUCING
A SQUALL LINE FROM THE TEXAS PANHANDLE TO THE LOWER PECOS VALLEY.
THESE STORMS WILL SPREAD EASTWARD AS THE UPPER LEVEL SYSTEM MOVES
RAPIDLY NORTHEAST ACROSS THE SOUTHERN PLAINS TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS WILL FORM IN ADVANCE OF THE
SQUALL LINE AND AFFECT THE WESTERN HALF OF NORTH TEXAS PRIOR SUNSET.
IT APPEARS THAT THE SQUALL LINE WILL AFFECT LOCATIONS FROM BOWIE TO
EASTLAND BY 700 PM.  THE STORMS SHOULD REACH A BONHAM...DALLAS...
HAMILTON LINE AROUND 1000 PM.  THE LINE OF STORMS ARE EXPECTED TO
SLOW AS THEY APPROACHES EAST TEXAS AFTER MIDNIGHT.

DAMAGING WINDS AND FREQUENT LIGHTNING WILL BE THE MAIN SEVERE WEATHER
THREAT FROM THE STRONGER STORMS.  FAVORABLE TURNING AND INCREASING
WIND SPEEDS WITH HEIGHT THROUGH THE VERTICAL WIND PROFILE...SUGGEST
ISOLATED ROTATING SUPERCELL THUNDERSTORMS CAPABLE OF LARGE HAIL
OR A BRIEF TORNADO.

IN ADDITION TO THE SEVERE WEATHER THREAT...THERE IS ALSO THE
POTENTIAL FOR HEAVY RAINFALL WEST OF A BONHAM...TO CORSICANA...TO
CAMERON LINE WHERE A FLASH FLOOD WATCH HAS BEEN ISSUED.

EMERGENCY MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS SHOULD
CONTINUE TO MONITOR ADDITIONAL STATEMENTS ISSUED BY THE NATIONAL
WEATHER SERVICE IN FORT WORTH AND BE READY FOR POSSIBLE ACTIVATION
TONIGHT.

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