Severe Thunderstorm Warning 58, NWS Tulsa, OK

AREA FORECAST DISCUSSION...MESOSCALE UPDATE
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
405 PM CDT FRI APR 9 2004

AT ATMOSPHERE IN SOUTHEAST OKLAHOMA CONTINUES TO DESTABILIZE AS
SURFACE DEW POINTS CLIMB INTO THE 50S...YIELDING LIFTED INDEX VALUES
TO -5 AT 20Z.

THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP OVER THE NEXT
COUPLE OF HOURS ALONG THE BOUNDARY THAT EXTENDS FROM NEAR NORMAN TO
JUST NORTH OF MCALESTER TO JUST SOUTH OF FORT SMITH.  DEEP LAYER
SHEAR SUPPORTS BOTH MULTICELL AND SUPERCELL CHARACTERISTICS.  WHILE
HAIL WILL BE THE PRIMARY THREAT FOR ESTABLISHED CELLS THAT MOVE
NORTHEAST OFF THE BOUNDARY INTO THE COOLER AIR...CELLS NEAR AND
SOUTH OF THE FRONT WILL HAVE GUST POTENTIAL TO SEVERE LIMITS.

STORM-SCALE ROTATION IS POSSIBLE GIVEN THE 0-6KM SHEAR.
STORM-RELATIVE HELICITY VALUES ARE SMALL IN THE WARM SECTOR FOR
STORMS FOLLOWING THE MEAN CELL MOTION...HOWEVER A MORE WEST TO EAST
STORM TRACK WOULD TRIPLE VALUES TO NEAR 300 M2/S2.  ANY STORM MOVING
RIGHT OF THE FLOW AND ON THE BOUNDARY WILL NEED TO BE MONITORIED FOR
TORNADO POTENTIAL GIVEN THE SMALL TEMPERATURE-DEW POINT SPREADS IN
AND IMMEDIATELY NORTH OF THE BOUNDARY.

SEE THE GRAPHICS AT WWW.WRH.NOAA.GOV/TULSA/SEVERE FOR MORE DETAILS.

FORECAST ID= 08

.TSA WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
OK...NONE.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT FRI APR 9 2004

ARZ001-002-010-011-019-020-029-OKZ049-053>076-101100-
ADAIR OK-BENTON AR-CARROLL AR-CHEROKEE OK-CHOCTAW OK-CRAIG OK-
CRAWFORD AR-CREEK OK-DELAWARE OK-FRANKLIN AR-HASKELL OK-LATIMER OK-
LE FLORE OK-MADISON AR-MAYES OK-MCINTOSH OK-MUSKOGEE OK-NOWATA OK-
OKFUSKEE OK-OKMULGEE OK-OSAGE OK-OTTAWA OK-PAWNEE OK-PITTSBURG OK-
PUSHMATAHA OK-ROGERS OK-SEBASTIAN AR-SEQUOYAH OK-TULSA OK-WAGONER OK-
WASHINGTON OK-WASHINGTON AR-

THIS OUTLOOK IS FOR NORTHWEST AND WEST CENTRAL ARKANSAS AS WELL AS
MUCH OF EASTERN OKLAHOMA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

...SLIGHT CHANCE OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH
TONIGHT GENERALLY SOUTH OF I-40...

EARLY THIS AFTERNOON AN UPPER LEVEL DISTURBANCE WAS MOVING TO THE
EAST ACROSS OKLAHOMA AND KANSAS.  SURFACE LOW PRESSURE WAS LOCATED
NEAR THE OKLAHOMA PANHANDLE WITH A FRONTAL BOUNDARY FROM NORTHWEST
OKLAHOMA TRAILING DOWN INTO THE SOUTHEASTERN PART OF THE STATE.
AN AREA OF RAIN ASSOCIATED WITH THE DISTURBANCE HAS BEEN MOVING
ACROSS THE AREA DURING THE DAY.  THE RAIN AND ASSOCIATED CLOUDS HAVE
LEFT THE ATMOSPHERE RELATIVELY COOL AND STABLE OVER MUCH OF THE
NORTHERN HALF OF THE AREA THIS AFTERNOON.  HOWEVER...IN SOUTHERN
AREAS LESS CLOUDS AND RAIN HAVE RESULTED IN WARMER TEMPERATURES AND
THE POTENTIAL FOR AN INCREASINGLY UNSTABLE ATMOSPHERE THROUGH THE
AFTERNOON.

AS A RESULT THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS
GENERALLY TO THE SOUTH OF I-40 LATE THIS AFTERNOON INTO TONIGHT IN
THE VICINITY OF THE FRONT.  LARGE HAIL AND DAMAGING WINDS WILL BE
THE PRIMARY THREAT.

SPOTTER / EMERGENCY MANAGEMENT ACTION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED IN THE SOUTH THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A COLDER AIRMASS WILL SETTLE OVER THE AREA SATURDAY WITH OCCASIONAL
RAIN ACROSS MAINLY NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS. THE
MAIN EFFECT WILL BE BREEZY CONDITIONS AND MUCH BELOW NORMAL
TEMPERATURES THIS WEEKEND. A LIGHT FREEZE IS POSSIBLE IN SOME
SHELTERED VALLEYS OF NORTHWEST ARKANSAS AND EXTREME NORTHEAST
OKLAHOMA SUNDAY NIGHT AND MONDAY NIGHT.

WWW.SRH.NOAA.GOV/TULSA CONTAINS ADDITIONAL TABULAR AND
GRAPHICAL INFORMATION

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
228 PM CDT FRI APR 9 2004

OKZ049-053-064>066-071-073-100100-
CHOCTAW OK-CREEK OK-MCINTOSH OK-OKFUSKEE OK-OKMULGEE OK-PITTSBURG OK-
PUSHMATAHA OK-
228 PM CDT FRI APR 9 2004

SEVERE THUNDERSTORM WATCH NUMBER 13 IN EFFECT UNTIL 800 PM CDT.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
314 PM CDT FRI APR 9 2004

OKZ066-092115-
OKMULGEE OK-
314 PM CDT FRI APR 9 2004

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A
SIGNIFICANT WEATHER ALERT EFFECTIVE UNTIL 415 PM CDT
FOR THE FOLLOWING COUNTY:

IN NORTHEAST OKLAHOMA
     OKMULGEE

AT 314 PM CDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 9 MILES
WEST OF WILSON...MOVING EAST AT 30 MPH. SOME LOCATIONS THAT WILL BE
AFFECTED BY THIS STORM INCLUDE...WILSON...OKMULGEE...HENRYETTA...
DEWAR...HOFFMAN...GRAYSON...SCHULTER...MORRIS AND ERAM.

THIS STORM WILL BE CAPABLE OF PRODUCING PEA SIZE HAIL AND WIND GUSTS
TO 40 MPH.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
353 PM CDT FRI APR 9 2004

OKZ065-092200-
OKFUSKEE OK-
353 PM CDT FRI APR 9 2004

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A
SIGNIFICANT WEATHER ALERT EFFECTIVE UNTIL 500 PM CDT
FOR THE FOLLOWING COUNTY:

IN EAST CENTRAL OKLAHOMA
     OKFUSKEE

AT 353 PM CDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 9 MILES
SOUTHWEST OF BOLEY...MOVING EAST AT 30 MPH. SOME LOCATIONS THAT WILL
BE AFFECTED BY THIS STORM INCLUDE...OKEMAH...WELEETKA...BEARDEN...
CLEARVIEW...PHAROAH...CASTLE AND BOLEY.

THIS STORM WILL BE CAPABLE OF PRODUCING SMALL HAIL AND WIND GUSTS TO
40 MPH.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
405 PM CDT FRI APR 9 2004

ARZ010-011-019-020-029-OKZ060-067>070-072-074>076-100200-
ADAIR OK-CHEROKEE OK-CRAWFORD AR-FRANKLIN AR-HASKELL OK-LATIMER OK-
LE FLORE OK-MADISON AR-MUSKOGEE OK-SEBASTIAN AR-SEQUOYAH OK-TULSA OK-
WAGONER OK-WASHINGTON AR-
405 PM CDT FRI APR 9 2004

SEVERE THUNDERSTORM WATCH NUMBER 59 IN EFFECT UNTIL 900 PM CDT.