Severe Thunderstorm Warning 107, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1015 AM CDT TUE MAY 7 2002

CURRENTLY WATCHING CONVECTION ACROSS SE KS AND SW MO THIS MORNING.
EXPECT CONVECTION TO WEAKEN AS THE MORNING PROGRESSES. OUTFLOW
BOUNDARY ROUGHLY APPROACHING A KJLN-KSGF LINE WAS SLOWLY SAGGING
SOUTH.  WITH A FAIRLY STRONG CAP NOTED PER AREA SOUNDINGS...THINK
CHANCES FOR SURFACE BASED CONVECTION THIS AFTERNOON ARE SLIM.  HOW
FAR SOUTH OUTFLOW BOUNDARY WILL MOVE REMAINS IN QUESTION...SO LOW
POPS ACROSS NE OK AND NW AR LOOK REASONABLE.  MAX TEMPERATURES LOOK
GOOD FOR THIS AFTERNOON AS WELL...SO NO UPDATE IS PLANNED THIS
MORNING.

FCSTID = 23

.TSA...
AR...NONE.
OK...NONE.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-081100-

EASTERN OKLAHOMA / NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
120 PM CDT TUE MAY 7 2002

...A SLIGHT CHANCE OF SEVERE THUNDERSTORMS TONIGHT ACROSS NORTHEAST
OKLAHOMA AND EXTREME NORTHWEST ARKANSAS...

ELEVATED THUNDERSTORMS CONTINUE ACROSS SOUTHWEST MISSOURI EARLY THIS
AFTERNOON AND WERE MOVING EAST...WHILE ADDITIONAL ACTIVITY HAS
DEVELOP ACROSS PORTIONS OF NORTH CENTRAL AND NORTHWEST
OKLAHOMA...AND WAS MOVING NORTHEAST INTO SOUTH CENTRAL AND SOUTHEAST
KANSAS.

ADDITIONAL THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND
EVENING ACROSS CENTRAL KANSAS NEAR A STATIONARY FRONT. THESE
THUNDERSTORMS MAY PUSH INTO NORTHEAST OKLAHOMA AND EXTREME NORTHWEST
ARKANSAS TONIGHT. A SECOND FOCUS FOR THUNDERSTORMS WILL BE THE
DRYLINE SITUATED ACROSS WESTERN OKLAHOMA. STORMS THAT DEVELOP AND
MOVE EAST OFF THE DRYLINE MAY ENTER NORTHEAST OKLAHOMA LATE TONIGHT.
SOME OF THESE THUNDERSTORMS COULD BECOME SEVERE WITH DAMAGING WINDS
THE PRIMARY THREAT.

.SPOTTER ACTIVATION...
SPOTTER ACTIVATION MAY BE REQUIRED OVER NORTHEAST OKLAHOMA AND FAR
NORTHWEST ARKANSAS AFTER MIDNIGHT.

.DISCUSSION...

ONGOING SHOWERS AND THUNDERSTORMS ACROSS NORTHERN
OKLAHOMA...SOUTHERN KANSAS AND SOUTHERN MISSOURI IS EXPECTED TO
WEAKEN THIS AFTERNOON AS THE LOW AND MID LEVEL JET DYNAMICS
SUBSIDE.

THUNDERSTORMS ARE EXPECTED TO DEVELOP AGAIN BY LATE AFTERNOON ALONG
A STATIONARY FRONT THAT EXTENDS FROM SOUTHWEST TO NORTHEAST ACROSS
KANSAS.  THUNDERSTORMS WILL MOST LIKELY EVOLVE INTO A MESOSCALE
CONVECTIVE SYSTEM TONIGHT AND HEAD TO THE SOUTHEAST. THIS ACTIVITY
WILL BE SUSTAINED AS A 55 KNOT LOW LEVEL JET IS REESTABLISHED ACROSS
OKLAHOMA AND SOUTHWEST MISSOURI THIS EVENING.  THUNDERSTORMS THAT
DEVELOP ALONG THE DRYLINE ACROSS PARTS OF WESTERN OKLAHOMA WILL MOVE
EAST....POSSIBLY MOVING INTO PARTS OF NORTHEAST OKLAHOMA AFTER
MIDNIGHT. DAYTIME HEATING WILL BE HAMPERED ACROSS MUCH OF WESTERN
OKLAHOMA BY EXTENSIVE MID AND HIGH LEVEL CLOUDS. THIS COMBINED WITH
A FAIRLY STRONG CAP MAY LIMIT WIDESPREAD THUNDERSTORM DEVELOPMENT.

THREAT TABLE
VALID THROUGH 1200 UTC WEDNESDAY

AREA 1...NORTH OF A BRISTOW TO WAGONER TO FAYETTEVILLE LINE
THUNDERSTORM PROBABILITY...20
SEVERE PROBABILITY IF STORMS OCCUR...50
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...05

THREAT AREAS DEFINE THE GREATEST RISK. PROBABILITIES ARE IN PERCENT.
SIGNIFICANT SEVERE IS DEFINED AS F1 OR GREATER WIND/TORNADO DAMAGE
AND/OR GOLFBALL SIZE HAIL OR LARGER.

RELATED GRAPHICAL INFORMATION CAN BE FOUND AT:
WWW.SRH.NOAA.GOV/TULSA

ARZ001-002-010-011-019-020-029-OKZ049-053>076-081100-

EASTERN OKLAHOMA / NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TULSA OK
315 PM CDT TUE MAY 7 2002

...SEVERE THUNDERSTORMS ARE EXPECTED THIS AFTERNOON THROUGH TONIGHT
ACROSS PARTS OF NORTHEAST OKLAHOMA AND PARTS OF NORTHWEST ARKANSAS...

THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP THIS AFTERNOON AND
EVENING ACROSS ACROSS PARTS NORTHEAST OKLAHOMA...CENTRAL AND
SOUTHERN SECTIONS OF KANSAS IN THE VICINITY OF A SURFACE BOUNDARY
AND STRONG MID LEVEL FLOW. THE SEVERE THREAT WILL EXTEND FURTHER
EAST BY EARLY THIS EVENING INTO EXTREME NORTHWEST ARKANSAS AS STORMS
ARE EXPECTED TO TAKE ON A MORE SOUTHEASTERLY MOVEMENT.

LATER TONIGHT...A SECOND FOCUS FOR THUNDERSTORMS WILL BE THE DRYLINE
SITUATED ACROSS WESTERN OKLAHOMA. STORMS THAT DEVELOP AND MOVE EAST
OFF THE DRYLINE MAY ENTER NORTHEAST OKLAHOMA LATE TONIGHT.

HAIL WILL BE THE PRIMARY THREAT WITH SEVERE STORMS THIS AFTERNOON
THROUGH TONIGHT.

.SPOTTER ACTIVATION...
SPOTTERS HAVE ALREADY BEEN ACTIVATED ACROSS NORTHEAST OKLAHOMA...AND
LIKELY WILL BE REQUIRED BY EARLY EVENING ACROSS NORTHWEST
ARKANSAS.

.DISCUSSION...

THUNDERSTORMS ACROSS NORTHERN OKLAHOMA AND SOUTHEAST KANSAS
OKLAHOMA HAVE DEVELOPED IN THE VICINITY OF A SURFACE BOUNDARY. UPPER
SUPPORT FROM AN UPPER LEVEL DISTURBANCE...50 TO 55 KNOT MID LEVEL
FLOW AND CAPES TO 4500 J/KG HAS RESULTED IN STRONG TO SEVERE
THUNDERSTORMS THIS AFTERNOON IN THE AFOREMENTIONED AREA. MID LEVEL
THICKNESS VALUES INDICATE THAT STORMS WILL TAKE ON A SOUTHEAST
MOTION AS THEY APPROACH SOUTHWEST MISSOURI AND NORTHWEST
ARKANSAS.

LATER TONIGHT...THUNDERSTORMS THAT DEVELOP ALONG THE DRYLINE ACROSS
PARTS OF WESTERN OKLAHOMA WILL MOVE EAST....POSSIBLY MOVING INTO
PARTS OF NORTHEAST OKLAHOMA AFTER MIDNIGHT.

THREAT TABLE
VALID THROUGH 1200 UTC WEDNESDAY

AREA 1...NORTH OF A BRISTOW TO WAGONER TO FAYETTEVILLE LINE
THUNDERSTORM PROBABILITY...100
SEVERE PROBABILITY IF STORMS OCCUR...100
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...30

THREAT AREAS DEFINE THE GREATEST RISK. PROBABILITIES ARE IN PERCENT.
SIGNIFICANT SEVERE IS DEFINED AS F1 OR GREATER WIND/TORNADO DAMAGE
AND/OR GOLFBALL SIZE HAIL OR LARGER.

RELATED GRAPHICAL INFORMATION CAN BE FOUND AT:
WWW.SRH.NOAA.GOV/TULSA