Tornado Warning 4, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OKLAHOMA CITY OK
1030 AM CDT SUN APR 21 1996

LATEST SFC CHART REVEALS WARM FRONT HAS MOVED N TO THE RED RIVER. SFC
DEW PTS HAVE REACHED THE LWR 60S IN SERN ZNS. EXPECT LOW LVL MOISTURE
TO INCREASE AND DEEPEN ACRS SERN 3/4 OF FA DURG AFTERNOON.

LOW LVL STATUS NR WARM FRONTAL BOUNDARY WL NOT DECREASE IN COVERAGE
UNTIL AFT 18Z...PER 12Z RUC OUTPUT. BUT FEEL SRN ZONES WL WARM QUICKLY
ONCE STATUS BRE|AKS OUT.

PARAMETERS CONTINUE TO BE FAVORABLE FOR SVR CONVECTION ACRS SERN 2/3 OF
FA THIS AFT...ESP AFT 20Z. WL MAKE SOME UPDATES TO 1ST TEMPS BASED ON
LATEST SAO TRENDS.

.OKC...
OK...NONE.
TX...NONE.

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OKZ004>053-TXZ083>090-212130-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE OKLAHOMA CITY OK
1230 PM CDT SUN APR 21 1996

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
TONIGHT OVER MUCH OF CENTRAL AND SOUTHERN OKLAHOMA AND WESTERN NORTH
TEXAS. THIS AREA OF MODERATE RISK IN GENERALLY EAST OF A LINE THAT
EXTENDS FROM SEYMOUR...TO HOBART...TO MEFORD. THERE IS A
SIGNIFICANT POTENTIAL FOR TORNADOES IN THIS AREA...IN ADDITION TO LARGE
HAIL AND DAMAGING WINDS. LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE
ACROSS MUCH OF CENTRAL AND EASTERN OKLAHOMA.

A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS THIS AFTERNOON AND EVENING
ACROSS THE REST OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS. LARGE HAIL
AND DAMAGING WINDS ARE THE PRIMARY THREAT WITH THESE
THUNDERSTORMS...HOWEVER ISOLATED TORNADOES ARE POSSIBLE.

SEVERAL FACTORS WILL COMBINE TO PRODUCE CONDITIONS FAVORABLE FOR SEVERE
THUNDERSTORM DEVELOPMENT. A LOW PRESSURE CENTER WILL CONTINUE TO
DEVELOP ACROSS THE TEXAS PANHANDLE DURING THE AFTERNOON...AS IT MOVES
SLOWLY EAST. COUNTER-CLOCKWISE CIRCULATION AROUND THE LOW WILL HELP PUSH
A WARM FRONT NORTH...ACROSS SOUTHERN OKLAHOMA AND INTO CENTRAL OKLAHOMA
BY LATE AFTERNOON. LOW LEVEL MOISTURE WILL INCREASE RAPIDLY BEHIND THIS
FRONT...BROUGHT BY STRONG SOUTHERLY LOW LEVEL WINDS. THIS WILL INCREASE
INSTABILITY AND PROVIDE FUEL FOR THUNDERSTORMS THAT DEVELOP. IN
ADDITION...STRONG WESTERLY UPPER LEVEL WINDS WILL ENHANCE A VERTICAL
WIND PROFILE FAVORABLE FOR SUPERCELL DEVELOPMENT.

A LACK OF SUFFICIENT LOW LEVEL MOISTURE MAY LIMIT THUNDERSTORM POTENTIAL
IN EXTREME WESTERN SECTIONS OF OKLAHOMA AND WESTERN NORTH TEXAS.

THIS IS A POTENTIALLY DANGEROUS WEATHER SITUATION. PEOPLE ARE URGED TO
REVIEW TORNADO SAFETY RULES AND KEEP ABREAST OF THE LATEST WEATHER
FORECASTS.

EMERGENCY MANAGERS AND STORM SPOTTER GROUPS SHOULD BE PREPARED FOR
ACTIVATION THIS AFTERNOON AND TONIGHT.

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