Severe Thunderstorm Warning 381, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
250 PM CDT THU AUG 21 2003

LATEST SURFACE DATA AND SATELLITE IMAGERY PLACE A WEAK COLD FRONT
BISECTING KANSAS FROM NE-SW WITH A MEAGER CUMULUS FIELD NOTED ALONG
THE BOUNDARY.  AFTERNOON THUNDERSTORMS HAVE AGAIN FORMED OVER AR
WITH THE PRIMARY AXIS SHIFTED SLIGHTLY FURTHER WEST THAN PREVIOUS
DAYS.  RADAR TRENDS WILL DETERMINE ANY EVENING WORDING FOR WESTERN
ARKANSAS LOCATIONS.

WEAK FRONT WILL ATTEMPT TO SLIDE SOUTH OVERNIGHT HOWEVER BELIEVE IT
WILL REMAIN NORTH OF THE KS/OK BORDER FOR MUCH OF THE PERIOD.  THUS
WILL CONTINUE WITH NEAR PERSISTENT OVERNIGHT LOW FORECAST DESPITE
WEAKENING GRADIENT PROVIDING CALM WINDS TOWARD MORNING.  WEAKENING
UPPER LEVEL DYNAMICS AND ASSOCIATED DECREASE IN LOW LEVEL JET
STRENGTH HAS YIELDED A DECREASE IN OVERNIGHT CONVECTIVE TRENDS.
THIS WILL CONTINUE AS SUBSTANTIAL FORCING SHIFTS WELL TO THE NORTH
AND EAST KEEPING PRECIP CHANCES ABSENT FROM TEXT PRODUCTS.

WEAK BOUNDARY TO SLIP INTO NORTHERN AREAS BY MID MORNING TOMORROW
HOWEVER HEATING MAY ACTUALLY BE ENHANCED WITHIN SURFACE TROUGH AS
OBSERVED TODAY.  THIS WILL FORCE A CONTINUATION OF THE HEAT ADVISORY
FOR TULSA METRO AREA.  PRECIP CHANCES WILL INCREASE SLIGHTLY BY
AFTERNOON WITHIN THE VICINITY OF THE SURFACE TROUGH AS WEAK
CONVERGENCE AND CONVECTIVE TEMPS COMBINE FORCES.  WILL ALSO CONTINUE
PRECIP CHANCES OVER ARKANSAS AS AIRMASS CHARACTERISTICS TO CHANGE
LITTLE.  WILL HOPE FOR SLIGHTLY LOWER DEWPOINTS ACROSS THE NORTH
TOMORROW NIGHT AND ALONG WITH LIGHT WINDS WILL ALLOW LOWS TO FALL TO
MORE SEASONAL VALUES.

NOT EXCITED ABOUT PRECIP CHANCES ON SATURDAY AS EXPANDING UPPER HIGH
CENTERED OVERHEAD.  NW AR MAY BE THE EXCEPTION WITH REMNANT SURFACE
BOUNDARY NEARBY.  EASTERLY WINDS WILL ALSO HELP KNOCK A FEW DEGREES
OFF THE HEAT.

WARMING AND DRY CONDITIONS RETURN BY SUNDAY AS UPPER HIGH EXPANDS
OVER THE CENTRAL U.S.  RIDGE AXIS MAY BECOME ELONGATED AND CENTERED
SLIGHTLY TO THE NORTH ALLOWING FOR A DEEPER EASTERLY FLOW AND
KEEPING TEMPS JUST SLIGHTLY ABOVE NORMAL.  POTENTIAL MID-WEEK
FRONTAL BOUNDARY STILL EVIDENT IN EXTENDED MODELS TO VARYING
DEGREES.  MODEL ENSEMBLES SUPPORT A MORE NORTHERLY POSITION OF
WESTERLIES WHICH WOULD LIKELY KEEP ANY BOUNDARY WELL TO THE
NORTH...SO LITTLE DAY TO DAY CHANGE REFLECTED IN THE EXTENDED.

PRELIM NUMBERS:

TUL    79  100   75   97 /  10   20   10   10
FSM    74   99   75   96 /  10   20   10   10
MLC    75   99   76   99 /   5   10   10   10
BVO    73  101   71   96 /  10   20   10   10
FYV    69   95   68   93 /  10   20   10   20
BYV    69   94   68   91 /  10   20   10   20
MKO    75  100   75   96 /  10   20   10   10
MIO    74   99   69   92 /  10   20   10   10
F10    75   99   75   98 /  10   20   10   10
HHW    75   97   76   97 /   5    5   10   10

FORECAST ID= 07

.TSA...
AR...NONE.
OK...HEAT ADVISORY THROUGH FRIDAY FOR ZONE OKZ060.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-221100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT THU AUG 21 2003

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

.DAY ONE...THIS AFTERNOON AND TONIGHT
ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE IN THE HIGHER TERRAIN OF
NORTHWEST ARKANSAS AND FAR SOUTHEAST OKLAHOMA THIS AFTERNOON.  THIS
ACTIVITY IS EXPECTED TO DISSIPATE BY EARLY EVENING WITH THE LOSS OF
SURFACE HEATING. ADDITIONAL STRONG TO SEVERE STORMS ARE EXPECTED TO
DEVELOP ALONG A COLD FRONT THAT IS CURRENTLY PUSHING SLOWLY SOUTH
ACROSS NORTHERN KANSAS AND MISSOURI. THESE STORMS HOWEVER WILL
LIKELY DISSIPATE BY LATE EVENING BEFORE REACHING THE AREA.

A HEAT ADVISORY IS ALSO IN EFFECT FOR TULSA COUNTY THROUGH FRIDAY.
SEE /OKCNPWTUL/ FOR DETAILS. HEAT INDICES THIS AFTERNOON AND FRIDAY
WILL RUN IN THE 104 TO 108 RANGE...WITH OVERNIGHT TEMPERATURES ONLY
FALLING TO NEAR OR JUST BELOW 80 DEGREES IN THE TULSA METRO.

WARNING PROBABILITIES FOR SEVERE THUNDERSTORMS AND TORNADOES CAN BE
FOUND IN THE OUTLOOK SECTION AT: WWW.SRH.NOAA.GOV/TULSA. GIVEN
PROBABILITIES REPRESENT THE POTENTIAL FOR A WARNING TO BE ISSUED AT
YOUR LOCATION.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY
LOW CHANCES FOR THUNDERSTORMS WILL CONTINUE FRIDAY AS THE COLD FRONT
WILL BE LOCATED ACROSS FAR NORTHEAST OKLAHOMA AND NORTHWEST
ARKANSAS. WHILE THIS FRONT EXPECTED TO WASHOUT AS IT MOVES SOUTHEAST
ACROSS OKLAHOMA FRIDAY NIGHT AND SATURDAY...LOW CHANCES FOR STORMS
WILL CONTINUE OUT AHEAD OF THE FRONT OR ANY OUTFLOW BOUNDARIES LAID
OUT BY PREVIOUS CONVECTION. AN UPPER RIDGE OF HIGH PRESSURE WILL
BUILD IN FOR THE REMAINDER OF THE WEEKEND AND INTO NEXT WEEK...
RESULTING IN HOT AND DRY CONDITIONS.

.SPOTTER / EMERGENCY MANAGEMENT ACTION STATEMENT...
SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT.

ADDITIONAL WEATHER INFORMATION CAN BE FOUND AT...
WWW.SRH.NOAA.GOV/TULSA

ARZ010-212100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
317 PM CDT THU AUG 21 2003

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY EFFECTIVE UNTIL 400 PM CDT
FOR THE FOLLOWING COUNTY:

IN NORTHWEST ARKANSAS
     WASHINGTON

AT 317 PM CDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
TUTTLE...MOVING NORTHWEST ABOUT 10 MPH. SOME LOCATIONS THAT WILL BE
AFFECTED BY THIS STORM INCLUDE...SHADY GROVE...TUTTLE...MAYFIELD...
HARMON...GOSHEN...JOHNSON AND SONORA.

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