Severe Thunderstorm Warning 296, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1055 AM CDT WED JUL 23 1997

AREA SOUNDINGS THIS MORNING LOOK MUCH LIKE THE PAST SEVERAL
DAYS...VALUES NEAR PEAK HEATING SHOWING LITTLE CAP...CAPES TO
AROUND 2000 J/KG AND A VERTICLE THETA-E PROFILE FAVORABILE FOR
MICROBURSTS.  THEREFORE WE WILL LIKELY AGAIN HAVE ISOLATED SEVERE
STORMS IN OUR CWA THIS AFTERNOON AND EVENING.  THE WIND PROFILE IS
WEAK SO CELL MOTIONS WILL BE SLOW.  LOW-LEVEL FLOW IS VERY WEAK SO
THE CELLS WILL LIKELY BE VERY QUICK UP AND DOWN WITH ONLY LIMITED
REDEVELOPMENT ON THE SUBSEQUENT BOUNDARIES...THUS KEEPING COVERAGE
IN THE SCATTERED CATEGORY AT BEST.

FEATURES TO FOCUS THE CONVECTION ARE SUBTLE...WATER VAPOR PICS THIS
MORNING SHOW THE UPPER LOW IN NE TEXAS WORKING SLOWLY WEST.  THE
DIFFLUENT FLOW AREAS SEEN IN THE LOOPS AND THE DIVERGENCE IN
GRIDDED DATA FIELDS SUGGEST THE BEST UPWARD MOTION WITH THIS SYSTEM
WILL BE TO THE EAST OF THE CENTER IN EXTREME SE OKLAHOMA...NE
TEXAS...SRN ARKANSAS AND N LOUISIANA.  AT THE SURFACE A WEAK
CONFLUENCE LINE WAS RESULTING IN SOME MOISTURE CONVERGENCE FROM
OSAGE COUNTY TO SOUTH OF FORT SMITH.  HOWEVER OROGRAPHIC LIFT IN
THE HILLS OF SE OKLAHOMA AND NW ARKANSAS WILL BE THE MOST LIKELY
SPOTS FOR STORM DEVELOPMENT.

THE CURRENT ZONES HAVE THESE IDEAS COVERED.  WILL MAKE ONLY MINOR
TWEAKS AS NECESSARY THIS AFTERNOON TO FOLLOW STORM TRENDS.

/8

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

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
10 AM CDT WED JUL 23 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0745 PM    3 NW GREENWOOD            AR   WIND DAMAGE
07/22/97   SEBASTIAN                      TREE DOWNED

ARZ001-002-010-011-019-029-OKZ054>076-241200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT WED JUL 23 1997

ISOLATED SHORT-LIVED SEVERE THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON AND EVENING...MAINLY ACROSS SOUTHEAST OKLAHOMA AND
WEST CENTRAL ARKANSAS.

TEMPERATURES IN THE 90S AND DEWPOINTS IN THE 70S WILL CAUSED THE
ATMOSPHERE TO BECOME INCREASINGLY UNSTABLE ACROSS EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THROUGH THE AFTERNOON.  THE BEST CHANCE FOR
THUNDERSTORM DEVELOPMENT SHOULD BE OVER THE HIGHER TERRAIN OF
SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS...GENERALLY ALONG AND
SOUTH OF INTERSTATE 40.  ANY THUNDERSTORM THAT FORMS WILL HAVE THE
POTENTIAL TO BECOME BRIEFLY SEVERE...WITH LARGE HAIL AND STRONG
DOWNBURST WINDS THE MAIN SEVERE WEATHER THREAT.  LIGHT WINDS ALOFT
ALSO SUGGEST THAT THUNDERSTORMS WILL MOVE SLOWLY...SO LOCALIZED
HEAVY RAINFALL WILL ALSO BE POSSIBLE.

THUNpDERSTORMS SHOULD DISSIPATE SHORTLY AFTER SUNSET WITH THE LOSS
OF DAYTIME HEATING.

EMERGENCY MANAGEMENT AGENCIES AND SPOTTER GROUPS SHOULD MONITOR THE
WEATHER CONDITIONS AND BE PREPARED FOR QUICK ACTIVATION THIS
AFTERNOON AND THIS EVENING.

ARZ001-002-010-011-019-029-OKZ054>076-241200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT WED JUL 23 1997

ISOLATED SHORT-LIVED SEVERE THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON AND EVENING...MAINLY ACROSS SOUTHEAST OKLAHOMA AND
WEST CENTRAL ARKANSAS.

TEMPERATURES IN THE 90S AND DEWPOINTS IN THE 70S WILL CAUSED THE
ATMOSPHERE TO BECOME INCREASINGLY UNSTABLE ACROSS EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THROUGH THE AFTERNOON.  THE BEST CHANCE FOR
THUNDERSTORM DEVELOPMENT SHOULD BE OVER THE HIGHER TERRAIN OF
SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS...GENERALLY ALONG AND
SOUTH OF INTERSTATE 40.  ANY THUNDERSTORM THAT FORMS WILL HAVE THE
POTENTIAL TO BECOME BRIEFLY SEVERE...WITH LARGE HAIL AND STRONG
DOWNBURST WINDS THE MAIN SEVERE WEATHER THREAT.  LIGHT WINDS ALOFT
ALSO SUGGEST THAT THUNDERSTORMS WILL MOVE SLOWLY...SO LOCALIZED
HEAVY RAINFALL WILL ALSO BE POSSIBLE.

THUNDERSTORMS SHOULD DISSIPATE SHORTLY AFTER SUNSET WITH THE LOSS
OF DAYTIME HEATING.

EMERGENCY MANAGEMENT AGENCIES AND SPOTTER GROUPS SHOULD MONITOR THE
WEATHER CONDITIONS AND BE PREPARED FOR QUICK ACTIVATION THIS
AFTERNOON AND THIS EVENING.