Special Weather Statement, NWS Tulsa, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
921 PM CDT THU JUL 12 2007

.UPDATE...
SEVERAL CLUSTERS OF THUNDERSTORMS HAVE DEVELOPED OVER THE
PAST FEW HOURS ACROSS THE OK PANHANDLE AND SW KS...IN
VICINITY OF AN OUTFLOW BOUNDARY THAT STRETCHES FROM SW KS
INTO NRN TX AND NWRN LA. THIS ACTIVITY INITIALLY DISPLAYED
LITTLE MOVEMENT...BUT STORM ARE BEGINNING TO SLIDE OFF TO
THE SE AS THEIR ASSOCIATED COLD POOL/S/ MATURE. PRIMARY
INSTABILITY AXIS RUNS ACROSS NW OK INTO SCNTRL OK...AND
WOULD EXPECT ONE OR MORE THUNDERSTORM COMPLEXES TO FOLLOW
THIS GENERAL TRACK OVERNIGHT. ACCORDINGLY...HAVE REMOVED
A FEW FAR NERN OK COUNTIES AND ALL OF NW AR FROM THE CURRENT
FLASH FLOOD WATCH. NIGHT SHIFT MAY NEED TO CONSIDER EXTENDING
THE WATCH INTO FRIDAY IF STORMS PERSIST BEYOND DAYBREAK.

UPDATED FLASH FLOOD WATCH HAS ALREADY BEEN ISSUED. OTHER
PRODUCTS WILL BE OUT SHORTLY.

&&

.PREV DISCUSSION... /ISSUED 325 PM CDT THU JUL 12 2007/

DISCUSSION...
OVERNIGHT MCS DEVELOPMENT IS AGAIN EXPECTED WITH THE EXACT
LOCATION AND TRACK OF THE COMPLEX REMAINING PROBLEMATIC. LARGE
COMPLEX CURRENTLY EXITING WESTERN ARKANSAS HAS STABILIZED THE
BOUNDARY LAYER ACROSS MUCH OF THE FORECAST AREA...HOWEVER RUC
ANALYZES PLUME OF STEEPER MID LEVEL LAPSE RATES REMAINING OVERHEAD
AND EXTENDING INTO WESTERN COLORADO. WOULD NOT BE SURPRISED TO SEE
SEVERAL THUNDERSTORM COMPLEXES DEVELOP DURING THE EVENING...ONE
NEARER THE SURFACE OUTFLOW BOUNDARY ACROSS WESTERN TEXAS...AND
ALSO FURTHER NORTHWARD AS LOW LEVEL UPSLOPE FLOW REDEVELOPS.
FAVORED A TRACK MORE EASTWARD OF THE RESULTANT MCS/S/ THAN
ADVERTISED BY MODEL QPF FIELDS...MORE IN LINE WITH EXPECTED
ORIENTATION OF 850MB INSTABILITY AXIS. THE HEAVIEST RAINS ARE
LIKELY TO REMAIN FURTHER SOUTH THAN WHAT OCCURRED THIS
MORNING...THOUGH ANY ADDITIONAL RAINS FURTHER NORTH WOULD RAISE
FLOODING CONCERNS. THESE FACTORS ALONG WITH AMPLE UNCERTAINTY WILL
KEEP CURRENT FLOOD WATCH THOUGH TONIGHT...WITH ANY ADJUSTMENTS
BETTER DEFINED AS EVENT UNFOLDS.

MCS DEVELOPMENT WILL REMAIN POSSIBLE FRIDAY INTO SATURDAY WITH A
GENERAL TREND TOWARD A MORE SOUTHWARD PLACEMENT OF THE HEAVIEST
AMOUNTS. CURRENT DATA SUGGEST FOCUS SHIFTS INTO NORTH TEXAS
POSSIBLY AFFECTING FAR SOUTHEAST OKLAHOMA FRIDAY NIGHT INTO
SATURDAY. WEAK SURFACE BOUNDARY MAY ALSO SLIDE INTO NORTHEAST
OKLAHOMA LATE SATURDAY BUT LITTLE IMPACT EXPECTED AT THIS TIME.

OBVIOUS IMPACT TO TEMPS FRIDAY INTO THE WEEKEND WILL BE EVOLUTION
AND TIMING OF THUNDERSTORM COMPLEXES. GENERALLY TOOK AN AVERAGE
FOR HIGH TEMPS AND FAVORED THE WARMER GUIDANCE FOR OVERNIGHT LOWS.

EXTENDED GUIDANCE CONTINUES TREND OF UPPER SHEAR AXIS DEVELOPING
NEAR THE AREA...WITH IMPACTS FROM SEVERAL DAYS OF MCS ACTIVITY
POSSIBLE ENHANCING THIS FEATURE. THE SHEAR AXIS IS FORECAST TO
MOVE LITTLE OR POSSIBLY SHIFT WESTWARD WITH TIME...WITH RESULTS
BEING DAILY PRECIP CHANCES AND TEMPERATURES CONTINUING AT OR
SLIGHTLY BELOW NORMAL.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   69  86  70  89 /  50  50  20  20
FSM   69  85  69  88 /  30  60  20  20
MLC   70  84  70  86 /  50  70  40  20
BVO   65  86  66  90 /  40  50  20  20
FYV   64  84  64  85 /  30  50  20  20
BYV   64  85  63  85 /  20  50  20  20
MKO   69  85  70  87 /  50  60  20  20
MIO   65  87  66  89 /  30  40  10  20
F10   69  84  70  86 /  60  70  20  20
HHW   72  85  71  87 /  30  70  50  40

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FLASH FLOOD WATCH UNTIL 7 AM FRIDAY FOR OKZ049-OKZ053-OKZ054-
     OKZ055-OKZ059-OKZ060-OKZ061-OKZ062-OKZ064-OKZ065-OKZ066-
     OKZ067-OKZ068-OKZ069-OKZ070-OKZ071-OKZ072-OKZ073-OKZ074-
     OKZ075-OKZ076.

AR...NONE.
&&

SHORT TERM...21
LONG TERM....18

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
111 PM CDT THU JUL 12 2007

ARZ001-002-010-011-019-020-029-OKZ049-053>076-131000-
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-
111 PM CDT THU JUL 12 2007

...SEVERE THUNDERSTORMS AND FLASH FLOODING POSSIBLE TODAY...

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SEVERE THUNDERSTORM.
	RISK...ELEVATED.
	AREA...SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

	AREA AT GREATEST RISK...SOUTHEAST OF A FAYETTEVILLE TO MCALESTER
          LINE.

FLASH FLOOD.
	RISK...ELEVATED.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

	AREA AT GREATEST RISK...SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.

HEAVY RAIN.
	RISK...SIGNIFICANT.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

	AREA AT GREATEST RISK...SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.

DISCUSSION...
A LARGE THUNDERSTORM COMPLEX WAS MOVING THROUGH EAST CENTRAL
OKLAHOMA...AND NORTHWEST AND WEST CENTRAL ARKANSAS THIS AFTERNOON.
THE STRONGEST THUNDERSTORMS WERE ALONG THE LEADING EDGE OF THIS
COMPLEX...WHERE THE HEAVIEST RAINFALL AND THREAT FOR SEVERE STORMS
WERE OCCURRING. ADDITIONAL THUNDERSTORM DEVELOPMENT WILL BE
POSSIBLE ALONG OUTFLOW BOUNDARIES ACROSS FAR SOUTHEAST
OKLAHOMA...AS THE ATMOSPHERE HAS NOT AFFECTED BY THE EARLIER
ACTIVITY. SHEAR AND INSTABILITY WILL SUPPORT STRONG TO SEVERE
THUNDERSTORMS...WITH STRONG WINDS AND HAIL THE PRIMARY THREATS.
HEAVY RAINFALL WILL ALSO OCCUR WITH ANY THUNDERSTORMS THAT DEVELOP.

THERE IS THE POTENTIAL FOR ANOTHER COMPLEX OF THUNDERSTORMS TO
DEVELOP LATE TONIGHT AND MOVE SOUTH INTO THE REGION. IF STORMS DO
MAKE IT INTO EASTERN OKLAHOMA AND NORTHWEST ARKANSAS...ENOUGH
INSTABILITY WILL BE PRESENT FOR STRONG TO SEVERE
THUNDERSTORMS...WITH THE THREAT OF STRONG WINDS AND HAIL. HEAVY
RAIN WILL ALSO REMAIN A CONCERN LATE TONIGHT DUE TO A VERY MOIST
ATMOSPHERE STILL IN PLACE.

FLASH FLOODING WILL CONTINUE TO BE A PROBLEM AS HEAVY RAIN FALLS ON
ALREADY SATURATED GROUND. A FLASH FLOOD WATCH IS IN EFFECT FOR THE
REGION THROUGH FRIDAY MORNING.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND OVERNIGHT. EMERGENCY
MANAGERS SHOULD MONITOR LATER FORECASTS FOR UPDATES ON THE
TIMING AND LOCATION OF ANOTHER THUNDERSTORM COMPLEX LATE TONIGHT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
FRIDAY...THUNDERSTORM POTENTIAL...HEAVY RAIN POTENTIAL.
SATURDAY THROUGH WEDNESDAY...THUNDERSTORM POTENTIAL.

EXTENDED DISCUSSION...
A COMPLEX OF THUNDERSTORMS...CAPABLE OF PRODUCING HEAVY
RAINFALL...MAY BE ONGOING FRIDAY MORNING. HOWEVER...THE
LOCATION...TIMING...AND STRENGTH OF THIS ACTIVITY IS STILL
UNCERTAIN...AND WILL BE REFINED IN LATER FORECASTS.

A NORTHWEST UPPER FLOW REGIME WITH WEAK LOW PRESSURE ESTABLISHED
ACROSS THE SOUTHERN PLAINS WILL NECESSITATE HAVING THUNDERSTORM
CHANCES IN THE FORECAST EACH DAY... PARTICULARLY FOR SCATTERED
DIURNAL ACTIVITY.

EMERGENCY MANAGEMENT PLANNING STATEMENT...
EMERGENCY MANAGERS SHOULD CONTINUE TO MONITOR LATER FORECASTS FOR
UPDATES ON THE HEAVY RAIN AND THUNDERSTORM POTENTIAL FRIDAY.

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
104 AM CDT FRI JUL 13 2007

OKZ076-130630-
LE FLORE OK-
104 AM CDT FRI JUL 13 2007

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A
SIGNIFICANT WEATHER ALERT EFFECTIVE UNTIL 130 AM CDT
FOR THE FOLLOWING COUNTY:

IN SOUTHEAST OKLAHOMA
     SOUTHERN LE FLORE

AT 104 AM CDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
WHITESBORO...MOVING EAST AT 10 MPH. SOME LOCATIONS THAT WILL BE
AFFECTED BY THIS STORM INCLUDE...BIG CEDAR...MUSE AND WHITESBORO.

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

LAT...LON 3476 9500 3458 9497 3454 9452 3483 9455