Severe Thunderstorm Warning 397, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
415 AM CDT SUN AUG 9 1998

SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPED IN THE MIDDLE LEVELS OF
THE ATMOSPHERE AS ANOTHER SHORT WAVE DROPPED SOUTHWARD INTO THE MEAN
TROUGH POSITION TO THE EAST. THE UPPER RIDGE SHOULD BUILD SLIGHTLY
EASTWARD AS THE TROUGH SLOWLY CONTINUES IN THAT DIRECTION AS WELL.
HOWEVER APPEARS THAT WEAK SHORT WAVES WILL CONTINUE TO DROP SOUTHWARD
TOWARDS THE FORECAST AREA. FOR TODAY SUSPECT THAT CURRENT ACTIVITY
WILL DIMINISH THIS MORNING. HOWEVER EXPECT THAT SHOWERS AND
THUNDERSTORMS WILL REDEVELOP WITH HEATING. WARMING MIDDLE LEVEL
TEMPERATURES SHOULD LIMIT WESTWARD EXTENT OF CONVECTION AND THUS BY
AFTERNOON WILL ONLY HAVE A MENTION OF PRECIPITATION IN THE EASTERN
ZONES.

MODELS SHOW A SIGNIFICANT SHORT WAVE MOVING ACROSS THE CENTRAL PLAINS
TONIGHT. BOTH THE 00 AND 03 UNIVERSAL COORDINATED TIME RUNS OF THE
ETA HAVE THIS FEATURE STRONGER THAN THE OTHER MODELS. ETA IS PROBABLY
ON THE RIGHT TRACK ALTHOUGH PERHAPS A BIT OVERDONE. THIS WOULD
SUGGEST THAT A MESOSCALE CONVECTIVE SYSTEM WILL FORM TO THE NORTH OF
THE FORECAST AREA. IF THE MODEL FORECAST IS CORRECT THEN THAT SYSTEM
WILL REMAIN TO THE NORTH THROUGH THE NIGHT. HOWEVER LOOKS LIKE SOME
MORE MIDDLE LEVEL ECHOES COULD ONCE AGAIN DEVELOP IN NORTHEAST
OKLAHOMA OR NORTHWEST ARKANSAS.

ACTIVITY TO THE NORTH WILL HELP PUSH A BOUNDARY INTO THE NORTHERN
PORTIONS OF THE FORECAST AREA ON MONDAY. ADDITIONAL SHOWERS AND
THUNDERSTORMS MAY DEVELOP ALONG AND NORTH OF THE FEATURE ON MONDAY
AND INTO MONDAY NIGHT.

TUL   98  74  97  75 /  20  20  20  20
FSM   99  70 100  71 /  30  20  20  20
MLC  101  73 102  73 /  20  10  10  10
BVO   98  73  95  73 /  20  20  20  20
FYV   94  67  92  66 /  20  20  30  20
IDB   99  69 101  70 /  30  20  10  10
BYV   94  66  91  65 /  20  20  30  20
MIO   95  72  92  69 /  20  20  30  20
MKO  100  73  98  74 /  20  20  20  20
F10   99  74  97  74 /  20  20  20  20
HHW  102  74 103  74 /  20  10  10  10

.TUL...
OK...NONE.
AR...NONE.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-101200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CDT SUN AUG 9 1998

ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE IN SOUTHEAST OKLAHOMA AND
NORTHWEST ARKANSAS TODAY AND THIS EVENING.

AN UPPER LEVEL DISTURBANCE WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO MOST OF SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS
THROUGH THE MORNING HOURS. THESE STORMS WILL BRING SOME BRIEF HEAVY
RAINS AND DANGEROUS LIGHTNING...AND MAY ALSO BRIEFLY PRODUCE LARGE
HAIL AND STRONG DOWNBURST WINDS. THEY ARE EXPECTED TO DIMINISH IN
COVERAGE AND INTENSITY BY MID TO LATE MORNING.

CLOUDS ARE EXPECTED TO BREAK ENOUGH TO ALLOW TEMPERATURES TO WARM INTO
THE 90S THIS AFTERNOON OVER SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.
IF THIS OCCURS...THE AIRMASS WILL BECOME UNSTABLE AND THUNDERSTORMS
COULD DEVELOP ALONG ANY WEAK SURFACE BOUNDARIES THAT THE MORNING SHOWERS
LEFT BEHIND. ISOLATED STORMS COULD BRIEFLY PRODUCE LARGE HAIL AND STRONG
WINDS INTO THE EARLY EVENING HOURS SOUTHEAST OF A LINE FROM FAYETTEVILLE
TO MCALESTER.

ANOTHER UPPER LEVEL DISTURBANCE WILL BRING A SLIGHT CHANCE FOR
THUNDERSTORMS TO NORTHEAST OKLAHOMA LATE TONIGHT...WITH A BETTER CHANCE
FOR THUNDERSTORMS NORTH OF THE AREA IN KANSAS.

ACTIVATION OF EMERGENCY MANAGEMENT AND STORM SPOTTER GROUPS FOR SEVERE
WEATHER OPERATIONS WILL NOT LIKELY BE NEEDED DUE TO THE EXPECTED
ISOLATED AND SHORT LIVED NATURE OF ANY SEVERE STORMS.

THIS OUTLOOK IS INTENDED TO PROVIDE GUIDANCE INFORMATION TO EMERGENCY
MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS CONCERNING
TORNADOES...SEVERE THUNDERSTORMS...HIGH WIND EVENTS...AND FLOODING.
INFORMATION CONCERNING OTHER HAZARDS CAN BE FOUND IN ADDITIONAL PRODUCTS
ISSUED BY THE TULSA NATIONAL WEATHER SERVICE OFFICE.

FOR MORE INFORMATION...VISIT THE NWS TULSA WORLD WIDE WEB PAGE AT
WWW.NWSTULSA.NOAA.GOV.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-101200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CDT SUN AUG 9 1998

ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE IN SOUTHEAST OKLAHOMA AND
NORTHWEST ARKANSAS TODAY AND THIS EVENING.

AN UPPER LEVEL DISTURBANCE WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO MOST OF SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS
THROUGH THE MORNING HOURS. THESE STORMS WILL BRING SOME BRIEF HEAVY
RAINS AND DANGEROUS LIGHTNING...AND MAY ALSO BRIEFLY PRODUCE LARGE
HAIL AND STRONG DOWNBURST WINDS. THEY ARE EXPECTED TO DIMINISH IN
COVERAGE AND INTENSITY BY MID TO LATE MORNING.

CLOUDS ARE EXPECTED TO BREAK ENOUGH TO ALLOW TEMPERATURES TO WARM INTO
THE 90S THIS AFTERNOON OVER SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.
IF THIS OCCURS...THE AIRMASS WILL BECOME UNSTABLE AND THUNDERSTORMS
COULD DEVELOP ALONG ANY WEAK SURFACE BOUNDARIES THAT THE MORNING SHOWERS
LEFT BEHIND. ISOLATED STORMS COULD BRIEFLY PRODUCE LARGE HAIL AND STRONG
WINDS INTO THE EARLY EVENING HOURS SOUTHEAST OF A LINE FROM FAYETTEVILLE
TO MCALESTER.

ANOTHER UPPER LEVEL DISTURBANCE WILL BRING A SLIGHT CHANCE FOR
THUNDERSTORMS TO NORTHEAST OKLAHOMA LATE TONIGHT...WITH A BETTER CHANCE
FOR THUNDERSTORMS NORTH OF THE AREA IN KANSAS.

ACTIVATION OF EMERGENCY MANAGEMENT AND STORM SPOTTER GROUPS FOR SEVERE
WEATHER OPERATIONS WILL NOT LIKELY BE NEEDED DUE TO THE EXPECTED
ISOLATED AND SHORT LIVED NATURE OF ANY SEVERE STORMS.

THIS OUTLOOK IS INTENDED TO PROVIDE GUIDANCE INFORMATION TO EMERGENCY
MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS CONCERNING
TORNADOES...SEVERE THUNDERSTORMS...HIGH WIND EVENTS...AND FLOODING.
INFORMATION CONCERNING OTHER HAZARDS CAN BE FOUND IN ADDITIONAL PRODUCTS
ISSUED BY THE TULSA NATIONAL WEATHER SERVICE OFFICE.

FOR MORE INFORMATION...VISIT THE NWS TULSA WORLD WIDE WEB PAGE AT
WWW.NWSTULSA.NOAA.GOV.