Severe Thunderstorm Warning 158, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
330 PM CDT MON MAY 8 2000

MAIN CHALLENGES THIS FORECAST PERIOD CONCERN THUNDERSTORM INITIATION
THIS EVENING...AND HEAVY RAINFALL POTENTIAL LATE TONIGHT INTO EARLY
TUESDAY MORNING. AIR MASS REMAINS STRONGLY CAPPED THIS AFTERNOON
WITH SPECIAL 18Z SOUNDING AT OUN REVEALING 700MB STILL NEAR 12C.
KINX VELOCITY DATA AND VISIBLE SATELLITE PICK UP ON TWO BOUNDARIES
APPROACHING THE AREA...THE COLD FRONT WHICH WAS MAKING FAIRLY GOOD
PROGRESS ACROSS CENTRAL OKLAHOMA...AND THE PREFRONTAL TROUGH MOVING
THROUGH OSAGE COUNTY.

EXPECT FRONT TO STALL...AND DEVELOPING SURFACE LOW PRESSURE IN WEST
TEXAS TO MOVE ALONG FRONT LATE TONIGHT. HEAVIEST RAINFALL EXPECTED
NEAR THE LOW TRACK...WITH POTENTIAL FOR HEAVY RAIN TONIGHT IN EXCESS
OF 3 INCHES POSSIBLE. UPPER LEVEL DIVERGENCE IS INCREASING WITH THE
APPROACHING JET...WHICH WILL ENHANCE LIFT LATER TONIGHT. THE LOW
LEVEL JET WILL ALSO SET UP IN A FAVORABLE POSITION TO FUEL
CONVECTION ALL NIGHT. STORMS WILL LIKELY INITIALLY BREAK OUT JUST
AHEAD OF THE COLD FRONT...AND THEN DEVELOP INTO AN MCS LATER
TONIGHT. GIVEN THE RECENT HEAVY RAINS AND FLOODING IN THE
AREA...WILL GO AHEAD AND ISSUE A FLASH FLOOD WATCH FOR THE NORTHEAST
OKLAHOMA ZONES.

WILL HAVE LIKELY POPS GOING FOR MOST ZONES TONIGHT...WITH CHANCE
WORDING INTO TUESDAY. LOW CLOUDS AND POSSIBLY SOME SHOWERS WILL
LINGER BEHIND THE SYSTEM INTO TUESDAY...SO TEMPS WILL BE COOLER AND
EXPECT SOME CLEARING BY TUESDAY EVENING. A RIDGE SETS UP ACROSS THE
AREA BY WEDNESDAY...SO NICE WARMUP EXPECTED WEDNESDAY.

FCSTID = 6
TUL   65  74  55  84 /  80  50  10   0
FSM   66  76  55  84 /  30  40  20   0
MLC   68  80  59  84 /  30  30  10   0
BVO   64  73  53  82 /  80  60  10   0
FYV   66  73  50  82 /  40  50  30   0
BYV   66  73  50  82 /  40  50  30   0
MIO   64  73  53  81 /  70  60  20   0
MKO   67  79  57  84 /  50  40  10   0
F10   67  79  57  84 /  50  40  10   0
HHW   68  80  59  84 /  30  30  10   0

THANKS FOR COORDINATION OUN/SGF/ICT.

.TUL...
AR...NONE.
OK...FLASH FLOOD WATCH FOR MONDAY NIGHT FOR ZONES OKZ054>064...
OKZ067.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-091200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
135 PM CDT MON MAY 8 2000

...A FEW SEVERE THUNDERSTORMS ARE EXPECTED TONIGHT ACROSS PARTS OF
NORTHEAST OKLAHOMA...

.SYNOPSIS...
SURFACE LOW PRESSURE CENTERED OVER CENTRAL KANSAS EARLY THIS MORNING
WILL DISSIPATE TODAY AS A NEW SURFACE LOW DEVELOPS IN NORTHEAST NEW
MEXICO. A COLD FRONT WAS ROUGHLY SOUTH OF A KMCI-KICT-KCDS LINE AS
OF EARLY THIS AFTERNOON. MOVEMENT OF THE FRONT IS EXPECTED TO SLOW
AS LOW PRESSURE DEVELOPS ACROSS NORTHWEST TEXAS/SOUTHWEST OKLAHOMA
THIS AFTERNOON. THE LOW WILL TRACK NORTHEAST ALONG THE FRONT
OVERNIGHT AND WILL BE LOCATED IN NORTHEAST OKLAHOMA BY SUNRISE
TUESDAY.

.PRIMARY HAZARD...
SEVERE THUNDERSTORMS ARE EXPECTED AFTER 7 PM THIS EVENING TO THE
NORTHWEST OF INTERSTATE 44. VERY LARGE HAIL OF UP TO 3 INCHES IN
DIAMETER AND WIND GUSTS TO 80 MILES AN HOUR WILL BE POSSIBLE WITH
SOME OF THE STORMS...ESPECIALLY NEAR THE KANSAS BORDER. THE THREAT
ALSO EXISTS FOR A COUPLE TORNADOES UNTIL AROUND MIDNIGHT...MAINLY IN
OSAGE AND PAWNEE COUNTIES.

ISOLATED SEVERE STORMS ARE POSSIBLE LATE TONIGHT IN MUCH OF THE REST
OF NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS. HAIL UP TO 1 INCH
IN DIAMETER AND WIND GUSTS TO 65 MILES AN HOUR WILL BE POSSIBLE WITH
THESE STORMS.

.DISCUSSION...
VERY WARM AIR ALOFT WILL INHIBIT THUNDERSTORM DEVELOPMENT THROUGH
THIS AFTERNOON. THE LACK OF LOW CLOUDS HAS ALLOWED CONSIDERABLE SURFACE
HEATING TO OCCUR. THUS...THE AIRMASS HAS BECOME EXTREMELY UNSTABLE
TO THE SOUTH OF THE COLD FRONT.

AN UPPER LEVEL DISTURBANCE WILL BE PUSHING OUT OF THE SOUTHERN ROCKIES.
COOLING ALOFT WILL BEGIN TO TAKE PLACE AHEAD OF THIS DISTURBANCE AND
RAPID THUNDERSTORM DEVELOPMENT IS EXPECTED TO OCCUR BY LATE THIS
AFTERNOON IN SOUTHERN KANSAS AND IN NORTHWEST AND NORTH CENTRAL
OKLAHOMA ALONG AND JUST NORTH OF THE SURFACE FRONT.

THESE THUNDERSTORMS WILL QUICKLY BECOME SEVERE AND WILL MOVE INTO
OSAGE AND PAWNEE COUNTIES AFTER 7 PM THIS EVENING. STORMS CAPABLE OF
VERY LARGE HAIL OF UP TO 3 INCHES IN DIAMETER AND DAMAGING WINDS OF
UP TO 80 MILES AN HOUR POSSIBLE WITH INITIAL DEVELOPMENT. ISOLATED
SUPERCELLS ARE POSSIBLE....THOUGH TORNADIC POTENTIAL MAY BE LIMITED.
UNFAVORABLE WIND PROFILES NORTH OF THE BOUNDARY...AND SURFACE WINDS
AHEAD OF THE BOUNDARY ARE LIMITING SHEAR IN THE LOWEST LEVELS OF THE
ATMOSPHERE. SURFACE WINDS ARE EXPECTED TO BACK THIS AFTERNOON IN
RESPONSE TO DEVELOPING LOW PRESSURE. EXTREME INSTABILITY IN PLACE
HOWEVER MAY OFFSET THESE FACTORS ENOUGH TO ALLOW A TORNADO OR TWO TO
OCCUR IN OSAGE AND PAWNEE COUNTIES.

LATER TONIGHT...THE STORMS WILL BECOME MORE MULTICELLULAR AND THE
MAIN THREAT WILL SHIFT FROM SEVERE WEATHER TO VERY HEAVY RAINFALL.
ISOLATED SEVERE STORMS WILL STILL BE POSSIBLE AFTER MIDNIGHT WITH
MARGINALLY SEVERE HAIL AND WINDS BEING THE MAIN SEVERE THREATS BY THIS
TIME.

IT APPEARS THE CAP WILL BE TOO STRONG TO ALLOW STORMS TO DEVELOP
SOUTH OF THE FRONTAL BOUNDARY FOR MOST IF NOT ALL OF THE AFTERNOON.
HOWEVER...SHOULD A STORM DEVELOP SOUTH OF THE BOUNDARY LATE THIS
AFTERNOON OR THIS EVENING...BACKED SURFACE WINDS AT THAT TIME WOULD
INCREASE TORNADIC POTENTIAL.

.OTHER HAZARDS...
THE HEAVY RAINFALL THREAT WILL INCREASE THE FLASH FLOODING POTENTIAL
IN FAR NORTHEAST OKLAHOMA OVERNIGHT...ESPECIALLY AREAS THAT SAW
HEAVY RAINS OVER THIS PAST WEEKEND. AREAS NORTHWEST OF INTERSTATE 44
MAY RECEIVE GREATER THAN 3 INCHES OF RAIN AS STORMS REPEATEDLY TRACK
OVER THE SAME AREAS.

.SPOTTER ACTIVATION...
EMERGENCY MANAGEMENT OFFICIALS AND STORM SPOTTER GROUPS TO THE
NORTHWEST OF INTERSTATE 44 SHOULD PREPARE FOR ACTIVATION BY EARLY
THIS EVENING. ACTIVATION MAY BE NECESSARY FURTHER TO THE SOUTHEAST
BY LATE TONIGHT.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-091200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
135 PM CDT MON MAY 8 2000

...A FEW SEVERE THUNDERSTORMS ARE EXPECTED TONIGHT ACROSS PARTS OF
NORTHEAST OKLAHOMA...

.SYNOPSIS...
A COLD FRONT WAS ROUGHLY SOUTH OF A KMCI-KICT-KCDS LINE AS OF EARLY
THIS AFTERNOON. MOVEMENT OF THE FRONT IS EXPECTED TO SLOW AS LOW
PRESSURE DEVELOPS ACROSS NORTHWEST TEXAS/SOUTHWEST OKLAHOMA THIS
AFTERNOON. THE LOW WILL TRACK NORTHEAST ALONG THE FRONT OVERNIGHT
AND WILL BE LOCATED IN NORTHEAST OKLAHOMA BY SUNRISE TUESDAY.

.PRIMARY HAZARD...
SEVERE THUNDERSTORMS ARE EXPECTED AFTER 7 PM THIS EVENING TO THE
NORTHWEST OF INTERSTATE 44. VERY LARGE HAIL OF UP TO 3 INCHES IN
DIAMETER AND WIND GUSTS TO 80 MILES AN HOUR WILL BE POSSIBLE WITH
SOME OF THE STORMS...ESPECIALLY NEAR THE KANSAS BORDER. THE THREAT
ALSO EXISTS FOR A COUPLE TORNADOES UNTIL AROUND MIDNIGHT...MAINLY IN
OSAGE AND PAWNEE COUNTIES.

ISOLATED SEVERE STORMS ARE POSSIBLE LATE TONIGHT IN MUCH OF THE REST
OF NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS. HAIL UP TO 1 INCH
IN DIAMETER AND WIND GUSTS TO 65 MILES AN HOUR WILL BE POSSIBLE WITH
THESE STORMS.

.DISCUSSION...
VERY WARM AIR ALOFT WILL INHIBIT THUNDERSTORM DEVELOPMENT THROUGH
THIS AFTERNOON. THE LACK OF LOW CLOUDS HAS ALLOWED CONSIDERABLE SURFACE
HEATING TO OCCUR. THUS...THE AIRMASS HAS BECOME EXTREMELY UNSTABLE
TO THE SOUTH OF THE COLD FRONT.

AN UPPER LEVEL DISTURBANCE WILL BE PUSHING OUT OF THE SOUTHERN ROCKIES.
COOLING ALOFT WILL BEGIN TO TAKE PLACE AHEAD OF THIS DISTURBANCE AND
RAPID THUNDERSTORM DEVELOPMENT IS EXPECTED TO OCCUR BY LATE THIS
AFTERNOON IN SOUTHERN KANSAS AND IN NORTHWEST AND NORTH CENTRAL
OKLAHOMA ALONG AND JUST NORTH OF THE SURFACE FRONT.

THESE THUNDERSTORMS WILL QUICKLY BECOME SEVERE AND WILL MOVE INTO
OSAGE AND PAWNEE COUNTIES AFTER 7 PM THIS EVENING. STORMS CAPABLE OF
VERY LARGE HAIL OF UP TO 3 INCHES IN DIAMETER AND DAMAGING WINDS OF
UP TO 80 MILES AN HOUR POSSIBLE WITH INITIAL DEVELOPMENT. ISOLATED
SUPERCELLS ARE POSSIBLE....THOUGH TORNADIC POTENTIAL MAY BE LIMITED.
UNFAVORABLE WIND PROFILES NORTH OF THE BOUNDARY...AND SURFACE WINDS
AHEAD OF THE BOUNDARY ARE LIMITING SHEAR IN THE LOWEST LEVELS OF THE
ATMOSPHERE. SURFACE WINDS ARE EXPECTED TO BACK THIS AFTERNOON IN
RESPONSE TO DEVELOPING LOW PRESSURE. EXTREME INSTABILITY IN PLACE
HOWEVER MAY OFFSET THESE FACTORS ENOUGH TO ALLOW A TORNADO OR TWO TO
OCCUR IN OSAGE AND PAWNEE COUNTIES.

LATER TONIGHT...THE STORMS WILL BECOME MORE MULTICELLULAR AND THE
MAIN THREAT WILL SHIFT FROM SEVERE WEATHER TO VERY HEAVY RAINFALL.
ISOLATED SEVERE STORMS WILL STILL BE POSSIBLE AFTER MIDNIGHT WITH
MARGINALLY SEVERE HAIL AND WINDS BEING THE MAIN SEVERE THREATS BY THIS
TIME.

IT APPEARS THE CAP WILL BE TOO STRONG TO ALLOW STORMS TO DEVELOP
SOUTH OF THE FRONTAL BOUNDARY FOR MOST IF NOT ALL OF THE AFTERNOON.
HOWEVER...SHOULD A STORM DEVELOP SOUTH OF THE BOUNDARY LATE THIS
AFTERNOON OR THIS EVENING...BACKED SURFACE WINDS AT THAT TIME WOULD
INCREASE TORNADIC POTENTIAL.

.OTHER HAZARDS...
THE HEAVY RAINFALL THREAT WILL INCREASE THE FLASH FLOODING POTENTIAL
IN FAR NORTHEAST OKLAHOMA OVERNIGHT...ESPECIALLY AREAS THAT SAW
HEAVY RAINS OVER THIS PAST WEEKEND. AREAS NORTHWEST OF INTERSTATE 44
MAY RECEIVE GREATER THAN 3 INCHES OF RAIN AS STORMS REPEATEDLY TRACK
OVER THE SAME AREAS.

.SPOTTER ACTIVATION...
EMERGENCY MANAGEMENT OFFICIALS AND STORM SPOTTER GROUPS TO THE
NORTHWEST OF INTERSTATE 44 SHOULD PREPARE FOR ACTIVATION BY EARLY
THIS EVENING. ACTIVATION MAY BE NECESSARY FURTHER TO THE SOUTHEAST
BY LATE TONIGHT.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
339 PM CDT MON MAY 08 2000

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

1140 PM    CHOUTEAU                  OK    .75 INCH HAIL
05/05/00   MAYES

0215 AM    WESTPORT                  OK    .88 INCH HAIL
05/06/00   PAWNEE

0230 AM    HASKELL                   OK    WIND DAMAGE
05/06/00   MUSKOGEE                        TREES BLOWN DOWN
                                           REPORTED BY LAW
                                           ENFORCEMENT

0250 AM    2 E WAGONER               OK    .88 INCH HAIL
05/06/00   WAGONER

0315 AM    WESTPORT                  OK    .88 INCH HAIL
05/06/00   PAWNEE

0330 AM    3 W PRUE                  OK    1 INCH HAIL
05/06/00   OSAGE

0330 AM    PRUE                      OK    1 INCH HAIL
05/06/00   OSAGE                           1 MILE WEST OF WALNUT
                                           CREEK STATE PARK

0515 AM    WESTPORT                  OK    .88 INCH HAIL
05/06/00   PAWNEE

0520 AM    BEGGS                     OK    .75 INCH HAIL
05/06/00   OKMULGEE               Z         REPORTED BY COOP OBSERVER

0630 AM    HOMINY                    OK    FLOOD
05/06/00   OSAGE                           6 HOUSES FLOODED

1030 AM    PRYOR                     OK    .75 INCH HAIL
05/06/00   MAYES