Severe Thunderstorm Warning 314, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
315 PM CDT SAT SEP 23 2000

MESONET SHOWING SURFACE LOW LOCATED A LITTLE TO THE NORTHEAST OF TUL
THIS AFTERNOON.  88-D ALSO SHOWING MULTIPLE BOUNDARIES THIS AFTERNOON
WITH DRYLINE TO THE SOUTH OF THE LOW ACROSS WAGONER/MUSKOGEE/MCINTOSH
COUNTIES WHILE MAIN COLD FRONT EXTENDING FROM JUST NORTH OF TUL UP
TOWARD MIAMI.  ALSO SOME REMNANTS OF OUTFLOW FROM THIS MORNING OFF TO
THE EAST...BUT THIS BOUNDARY MAY BE WASHING OUT AND BEGINNING TO LIFT
SOME BACK TO THE NORTHEAST.  MESONET ALSO SHOWING GOOD CONTRAST IN
TEMPS WITH 60S IN OSAGE/PAWNEE COUNTIES WHILE 90S JUST TO THE SOUTH
AND EAST OF TULSA.

EXPECT WARM SECTOR TO BECOME ACTIVE BY LATER THIS AFTERNOON INTO THIS
EVENING AND SHOULD BE GETTING CLOSE TO SEEING FIRST STORMS FIREUP
SOON.  FRONT HAS BEEN VERY SLOW TO MAKE MUCH PROGRESS TO THE SOUTH
AND EAST THRU THE AFTERNOON AND WILL LIKELY SEE SOME ELEVATED
COVECTION AGAIN LATER TONIGHT THAT WILL BE MAINLY OVER SOUTHERN AND
EASTERN AREAS AGAIN.  THROUGH TONIGHT WITH BETTER CHANCE OF PRECIP
OVER THE SOUTHERN AND EASTERN PARTS OF THE AREA WILL CONTINUE LIKELY
POPS THERE WITH CHANCE POPS ELSEWHERE.  SURFACE BOUNDARY WILL STILL
LIKELY BE HUNG UP OVER THE SOUTHERN PART OF THE AREA DURING THE DAY
ON SUNDAY WITH WIDESPREAD CLOUDS AND COOLER AIR CONTINUING TO SPREAD
INTO THE AREA FROM THE NORTHWEST.  WITH UPPER SYSTEM MOVING ACROSS
THE PLAINS SUNDAY INTO SUNDAY NIGHT WILL CONTINUE LIKELY POPS IN MOST
AREAS FOR NOW...BUT WILL HAVE TO SEE WHAT AFFECTS OVERNIGHT PRECIP
TONIGHT HAS ON THE WHOLE PICTURE.

TEMPS WILL SEE LITTLE DIURNAL RANGE SUNDAY AND SUNDAY WITH
CLOUDS/PRECIP IN THE PICTURE.  EXCEPTION WILL BE IN THE FAR SOUTH
UNTIL FRONT FINALLY GET A GOOD SHOVE ON THRU.

EXTNEDED PART OF THE FORECAST LOOKS DRY THRU MUCH OF THE UPCOMING
WEEK ONCE THIS SYSTEM CLEARS BY MONDAY.

FCSTID = 4
TUL   60  64  48  63 /  50  70  70  30
FSM   66  72  53  64 /  60  70  70  30
MLC   64  70  50  65 /  60  70  70  30
BVO   56  60  44  60 /  40  60  60  30
FYV   63  67  45  60 /  60  70  70  30
BYV   63  67  45  60 /  60  70  70  30
MIO   57  63  45  60 /  50  60  60  30
MKO   58  62  48  62 /  50  60  60  30
F10   60  64  48  63 /  50  70  70  30
HHW   66  76  52  66 /  60  70  70  30

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

ARZ001-002-010-011-019-020-029-OKZ049-053>076-241100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT SAT SEP 23 2000

...A FEW SEVERE THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON
IN NORTHWEST ARKANSAS AND SOUTHEAST OKLAHOMA...

...ISOLATED SEVERE THUNDERSTORMS ARE ALSO POSSIBLE OVERNIGHT ACROSS
ALL OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS...

.SYNOPSIS...
EARLY THIS AFTERNOON A SURFACE LOW PRESSURE CENTER WAS LOCATED JUST
NORTH OF TULSA...AND A COLD FRONT EXTENDED SOUTHWESTWARD FROM THE
LOW TO NEAR WICHITA FALLS TEXAS.  THE SURFACE LOW AND COLD FRONT ARE
EXPECTED TO SLOWLY MOVE EASTWARD THIS AFTERNOON AND THEN SOUTHEAST
TONIGHT.  THE FRONT IS EXPECTED TO BECOME STATIONARY ACROSS EXTREME
SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS LATE TONIGHT.

.PRIMARY HAZARD...
A FEW SEVERE THUNDERSTORMS MAY DEVELOP ALONG THE COLD FRONT FROM
NORTHWEST ARKANSAS INTO SOUTHEAST OKLAHOMA LATE THIS AFTERNOON.
LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN THREAT WITH THESE
STORMS.

ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP OVERNIGHT ANYWHERE IN
EASTERN OKLAHOMA OR NORTHWEST ARKANSAS. LARGE HAIL WILL BE THE MAIN
THREAT WITH THESE STORMS.

.DISCUSSION...
AN OUTFLOW BOUNDARY FROM THIS MORNINGS STORMS EXTENDED FROM THE
SURFACE LOW SOUTHEASTWARD TO NEAR FORT SMITH EARLY THIS AFTERNOON.
A VERY MOIST AND UNSTABLE AIRMASS IS IN PLACE BETWEEN THE COLD FRONT
AND THE OUTFLOW BOUNDARY.  AS THE ATMOSPHERE BEHIND THE OUTFLOW
BOUNDARY RECOVERS...THE MOIST AND UNSTABLE AIRMASS WILL OVERSPREAD
ALL OF THE AREA AHEAD OF THE COLD FRONT.

BY LATE AFTERNOON...TEMPERATURES SHOULD BE SUFFICIENTLY WARM TO
INITIATE THUNDERSTORM DEVELOPMENT ALONG OR JUST AHEAD OF THE COLD
FRONT...GENERALLY FROM A BENTONVILLE TO MCALESTER LINE AFTER 3 PM.
THE AMOUNT OF INSTABILITY AND THE VERTICAL WIND PROFILE EXPECTED IN
THE AREA AHEAD OF THE FRONT THIS AFTERNOON...SUGGEST THAT A FEW
SUPERCELLS WILL BE POSSIBLE. THE STORMS WILL MOVE TO THE EAST OR
SOUTHEAST AT 20 TO 25 MPH...AND SHOULD BEGIN TO DIMINISH AFTER
SUNSET.

CONSIDERABLE CLOUD COVER MAY HAMPER DESTABILIZATION AND ULTIMATELY
THUNDERSTORM FORMATION THIS AFTERNOON.  ANOTHER LIMITING FACTOR WILL
BE THE DEPTH OF THE LOW-LEVEL MOISTURE.  LOW-LEVEL WINDS ARE
EXPECTED TO VEER TO THE SOUTHWEST AND WEST AHEAD OF THE BOUNDARY
WHICH MAY PUSH THE DEEPER MOISTURE EASTWARD BEFORE STORMS CAN
INITIATE NEAR THE COLD FRONT.

OVERNIGHT...A MODERATELY STRONG LOW LEVEL JET WILL SET UP OVERNIGHT
ALLOWING MOIST UNSTABLE AIR TO FLOW UP AND OVER THE SHALLOW COOL
AIRMASS AT THE SURFACE. SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP OVERNIGHT AND ELEVATED INSTABILITY WILL BE SUFFICIENT FOR A
FEW STORMS TO PRODUCE LARGE HAIL. THE GREATEST THREAT FOR SEVERE
WEATHER OVERNIGHT WILL BE NORTH OF THE STALLED SURFACE FRONT.

AT THIS TIME IT APPEARS THAT THE ELEVATED ACTIVITY WILL BEGIN OVER
WESTERN OKLAHOMA AND NORTHWEST TEXAS THIS EVENING...AND SPREAD EASTWARD
INTO EASTERN OKLAHOMA AND WESTERN ARKANSAS AFTER MIDNIGHT.
CONSIDERABLE UNCERTAINTY EXISTS WITH THIS SCENARIO...SO SPOTTER
GROUPS AND EMERGENCY MANAGERS SHOULD CONTINUE TO MONITOR THE
SITUATION CLOSELY.

.OTHER HAZARDS...
AN EXTREME FIRE DANGER WILL EXIST AGAIN THIS AFTERNOON OVER MOST OF EASTERN
OKLAHOMA EXCEPT NEAR THE ARKANSAS BORDER WHERE SIGNIFICANT RAIN HAS
FALLEN OVERNIGHT.

.SPOTTER ACTIVATION...
EMERGENCY MANAGEMENT OFFICIALS AND STORM SPOTTER GROUPS IN SOUTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS SHOULD BE PREPARED FOR ACTIVATION
LATE THIS AFTERNOON.  EMERGENCY MANAGEMENT OFFICIALS AND STORM
SPOTTER GROUPS THROUGHOUT EASTERN OKLAHOMA AND NORTHWEST ARKANSAS
SHOULD CONTINUE TO MONITOR THE SITUATION AND BE PREPARED FOR
ACTIVATION AFTER MIDNIGHT TONIGHT.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
424 PM CDT SAT SEP 23 2000

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

0415 PM    LOST CITY                 OK    1 INCH HAIL
09/23/00   CHEROKEE                        FIRE DEPARTMENT