Flash Flood Warning 9, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
812 PM CDT WED MAY 29 2013

.UPDATE...
ADJUSTED ALL ELEMENTS FOR THE REST OF TONIGHT...ESPECIALLY
TO DECREASE STORM CHANCES OVER WESTERN NORTH TEXAS AND
FAR SOUTHWESTERN OKLAHOMA AND TO INCREASE THEM OVER
NORTHERN OKLAHOMA AND EAST OF I-35.

&&

.DISCUSSION...
THE RISK FOR SEVERE THUNDERSTORMS CONTINUES MAINLY
NORTH OF I-40 AND EAST OF I-35 THROUGH MIDNIGHT TONIGHT.
THERE MAY A SLIGHTLY ENHANCED RISK FOR TORNADOES OVER
BECKHAM...WASHITA...AND CUSTER COUNTIES OVER THE NEXT
TWO HOURS.

WILL CLOSELY MONITOR CURRENT STORMS OVER BECKHAM COUNTY THAT WILL
AFFECT LOCATIONS NEAR A ELK CITY TO PONCA CITY LINE OVER THE NEXT
SEVERAL HOURS. THESE STORMS APPEAR TO BE INGESTING THE BEST
INSTABILITY FROM AN INCREASING LOW LEVEL JET. THERE IS A LOW
CHANCE FOR TORNADOES NEAR AN ELK CITY TO CORDELL TO WEATHERFORD
LINE OVER THE NEXT HOUR OR TWO...ESPECIALLY AS LOW LEVEL WINDS
INCREASE. HEAVY RAINFALL OF 1 TO 3 INCHES AND LOCALIZED FLOODING
WITH TRAINING CELLS MAY OCCUR IN THESE AREAS AS WELL.

AT THIS TIME...ADDITIONAL SEVERE STORMS SEEM UNLIKELY FOR
MUCH OF THE OKLAHOMA CITY METRO AREA...EXCEPT FOR THE POSSIBLE
EXCEPTION OF LOCATIONS NORTHWEST OF AN EL RENO TO GUTHRIE LINE.

ADDITIONAL SHOWERS AND STORMS WILL CONTINUE ACROSS SOUTHERN
OKLAHOMA...EAST OF I-35 AS WELL. DUE TO WEAKER SHEAR...THESE
STORMS MAY REMAIN LESS ORGANIZED AND HAVE A LESS CHANCE OF
BEING SEVERE.

STRONG CAPPING WILL LIKELY NOT ALLOW FOR ANY STORM
DEVELOPMENT ACROSS WESTERN NORTH TEXAS AND FAR SOUTHWESTERN
OKLAHOMA FOR THE REMAINDER OF TONIGHT. KEPT A 20 PERCENT
CHANCE FOR STORMS IN THESE AREAS.

AFTER MIDNIGHT TONIGHT...SEVERE STORMS REMAIN UNLIKELY WITH
THE BEST RAIN CHANCES EAST OF I-35.

MBS

&&

.PREV DISCUSSION... /ISSUED 648 PM CDT WED MAY 29 2013/

DISCUSSION...
PLEASE SEE THE 00Z AVIATION DISCUSSION BELOW.

AVIATION...
SHOWERS AND THUNDERSTORMS CONTINUE ACROSS OK EARLY THIS EVENING.
ONE LINE OF STORMS WAS LOCATED FROM JUST SOUTH OF PNC THROUGH OUN.
ANOTHER LINE WAS LOCATED EAST OF WWR TO WEST OF CSM. HAVE INCLUDED
TEMPOS TO REFLECT THESE LINES...WITH A MAIN THREAT OF SEVERE WIND
GUSTS EXCEEDING 50 KT. AFTER THE TSRA DIMINISHES LATE
TONIGHT...MVFR CIGS ARE EXPECTED AGAIN AND SOUTH WINDS NEAR 20 KT
WILL CONTINUE TO IMPACT MOST OF THE TERMINALS. AN AWW WAS ISSUED
FOR OKC...BUT HAS JUST EXPIRED AS THE LINE OF STORMS MOVES OUT OF
THE AREA.

PREV DISCUSSION... /ISSUED 327 PM CDT WED MAY 29 2013/

DISCUSSION...
CURRENTLY...A LINE OF SEVERE CONVECTION REMAINS FOCUSED ALONG THE
DRY LINE ACROSS THE TX PANHANDLE. AHEAD OF THE DRY LINE...IN THE
WARM SECTOR...A SCATTERED LINE OF SUB SEVERE THUNDERSTORMS
CONTINUE TO DEVELOP ACROSS FAR SWRN OK AND WRN N TX. THERE REMAINS
A DECENT CAPPING INVERSION ACROSS CENTRAL AND NRN OK.
HOWEVER...WITH THE RECENT DEVELOPMENT ACROSS SWRN OK AND WRN N
TX...THUNDERSTORM DEVELOPMENT WILL LIKELY CONTINUE THROUGH THE
EVENING ACROSS WRN OK...AND EVENTUALLY INTO CENTRAL OK. THE
PRIMARY SEVERE THREAT WILL BE ACROSS FAR WRN/NWRN OK AS THE DRY
LINE SLOWLY PUSHES EASTWARD THIS AFTERNOON...NEAR THE OK/TX
BORDER. SCATTERED CONVECTION WILL LIKELY SPREAD INTO THE METRO
AFTER 6 PM...WITH FREQUENT LIGHTNING...SEVERE HAIL...AND WIND
GUSTS OF 50 TO 60 MPH ALL POSSIBLE. THE TORNADO THREAT FOR THE OKC
METRO REMAINS LOW THROUGH THE EVENING HOURS.

TONIGHT...
THE LARGE SCALE MID-TROPOSPHERIC TROUGH WILL REMAIN NEGATIVELY
TILTED OVERNIGHT THROUGH THURSDAY MORNING...WITH THE 500MB TROUGH
AXIS ORIENTED FROM SRN ALBERTA THROUGH THE SRN PLAINS. WITH THE
PRIMARY SFC LOW LIFTING N/NE ACROSS SRN KS OVERNIGHT...SHOWER AND
THUNDERSTORMS WILL LIKELY PERSIST THROUGH THU MORNING. AS
INDIVIDUAL STORMS MOVE OFF THE DRY LINE LATER THIS EVENING AND
ACTIVITY INCREASES ACROSS WRN OK...EXPECT THESE STORMS TO MERGE
INTO A LINE AS THEY APPROACH THE CENTRAL OK/OKC METRO. THIS WILL
LESSEN THE OVERALL TORNADO THREAT THIS EVENING FOR THE METRO.
HOWEVER...THE DAMAGING WIND THREAT AND LARGE HAIL POTENTIAL WILL
CONTINUE AS THIS AREA OF STORMS MOVE EAST THROUGH THE EVENING.

THURSDAY...
THE MAIN FORECAST CONCERN WILL BE FOCUSED ON THUNDERSTORM CHANCES FOR
THU AFTN. THE PRIMARY 500MB TROUGH WILL REMAIN NEGATIVELY TILTED
AND FOCUSED ACROSS THE WRN CONUS...FROM THE PAC NW THROUGH THE SRN
PLAINS. IN RESPONSE... ANOTHER SHORTWAVE RIDING THE LARGER TROUGH
WILL SWEEP OFF SERN CO...WITH THE DRY LINE MAKING A SURGE
EASTWARD...THIS TIME INTO WRN/N CENTRAL OK. AGREEMENT FROM SHORT
RANGE GUIDANCE WOULD PLACE IT SOMEWHERE JUST SHY OF AN ENID TO
WEATHERFORD TO CROWELL TX LINE. BUFR SOUNDINGS FOR NWRN/N CENTRAL
OK SHOW VERY STEEP LAPSE RATES AND FAVORABLE HODOGRAPHS THROUGH
THE LATE AFTN/EARLY EVENING. WITH BACKING SFC WINDS NEAR THE SFC
LOW THROUGH 00Z FRI...0-1 AND 0-3KM HELICITIES WILL INCREASE.
OVERALL...WITH THE SURGING DRY LINE FOR FOCUSED LIFT AND DECENT
DYNAMICS...THE POTENTIAL FOR SUPERCELLS WITH LARGE HAIL...
DAMAGING WINDS... AND TORNADOES LOOKS DECENT THU AFTN ACROSS N
CENTRAL OK THROUGH SWRN OK AND FAR WRN N TX BEFORE THE DRY LINE
RETREATS BACK TO THE WEST OVERNIGHT. AT THE MOMENT...THE BEST
POTENTIAL FOR TORNADOES WILL BE NEAR THE SFC LOW TRACK AND THE
BEST SURGE IN THE DRY LINE...WHICH WILL BE ACROSS N CENTRAL OK
THROUGH W CENTRAL OK. ELSEWHERE...ACROSS CENTRAL OK AND THE OKC
METRO...THE DRY LINE WILL LIKELY STALL JUST WEST OF THE
METRO...NEAR EL RENO. HOWEVER...ANY STORMS THAT MOVE OFF THE DRY
LINE AND EASTWARD...WILL BE CAPABLE OF TORNADOES...LARGE HAIL AND
DAMAGING WINDS. THROUGH THE EVENING...STORMS WILL LIKELY FORM INTO
A LINE...SHIFTING EASTWARD THROUGH THE EVENING AND OVERNIGHT AS
THE SFC LOW LIFTS E/NE ONCE AGAIN.

FRIDAY...
SEVERE WEATHER POTENTIAL WILL CONTINUE FRIDAY AS ANOTHER SHORT WAVE
RIDES SEWRD AROUND THE PRIMARY 500MB TROUGH AS IT FINALLY BEGINS
TO TRANSITION OVER THE CENTRAL PLAINS. WITH THE SFC LOW TAKING A
MORE SOUTHWARD TRACK DURING THE DAY FRIDAY...THIS WILL BRING THE
WARM FRONT INTO PLAY ACROSS NRN AND NWRN OK...DROPPING SWRD
THROUGH THE AFTN JUST NORTH OF THE OKC METRO. WHILE OUT WEST...THE
DRY LINE MAKES ANOTHER PUSH EASTWARD ACROSS WRN N TX AND S/SWRN
OK. IN RESPONSE TO THE SFC LOW/WARM FRONT/DRY LINE COMBINATION...
SFC WINDS WILL ONCE AGAIN BACK THROUGH THE AFTERNOON... RESULTING
IN INCREASED O-1KM AND 0-3KM HELICITIES THROUGH. MID-LEVEL LAPSE
RATES WILL REMAIN STEEP FROM CENTRAL OK THROUGH WRN N TX...AND
DEEP LAYER SHEAR WILL REMAIN SUFFICIENT FOR SUSTAINED UPDRAFTS AND
SUPERCELLS. AT THE MOMENT...THE GREATEST THREATS WILL BE
LARGE DAMAGING HAIL... DAMAGING WIND GUSTS... AND TORNADOES FROM
NORTH CENTRAL OK THROUGH WRN N TX.

NOT TO BE LEFT OUT...FLOODING AND FLASH FLOODING COULD BE POSSIBLE
FRIDAY AS MID-RANGE GUIDANCE SHOWS PERSISTENT SHOWER AND
THUNDERSTORM DEVELOPMENT ALONG THE WARM FRONT ACROSS NRN OK.

FOR THE WEEKEND...
SHOWERS AND THUNDERSTORMS WILL LIKELY PERSIST EARLY...EXITING TO
THE SE THROUGH THE AFTERNOON. BROAD HIGH PRESSURE WILL SET UP OVER
THE CENTRAL PLAINS...WITH DRY CONDITIONS FOR SUNDAY INTO MONDAY.

KURTZ

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

17/03

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORMAN OK
1056 PM CDT WED MAY 29 2013

OKZ004>048-050>052-TXZ083>090-301700-
HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WASHITA-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
1056 PM CDT WED MAY 29 2013

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...REST OF TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK FOR SEVERE STORMS...MAINLY ACROSS OKLAHOMA
FOR THE REST OF TONIGHT.

LOCATION...
THE SLIGHT RISK AREA IS MAINLY EAST OF A LINE FROM ALVA TO ELK CITY
TO MANGUM TO CHICKASHA TO WAURIKA.

THE SLIGHT RISK AREA INCLUDES THE OKLAHOMA CITY METRO...
WEATHERFORD...PONCA CITY...ADA...ARDMORE...AND DURANT AREAS.

IMPACTS...
THE STRONGEST STORMS WILL BE CAPABLE OF PRODUCING...

DAMAGING WIND GUSTS UP TO 65 MPH...
LARGE HAIL UP TO THE SIZE OF GOLF BALLS...
HEAVY RAINFALL OF 1 TO 3 INCHES WITH LOCALIZED FLOODING...

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS IS THROUGH
6 AM THURSDAY MORNING.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS
THE RISK AREA HAVE BEEN ACTIVATED AND SHOULD CONTINUE TO BE
READY FOR SEVERE WEATHER OPERATIONS TONIGHT.

DISCUSSION...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE
ACROSS MUCH OF OKLAHOMA FOR THE REST OF TONIGHT. AN APPROACHING
LOW PRESSURE DISTURBANCE AND A STRONG LOW LEVEL JET WILL CONTINUE
TO PROVIDE LARGE SCALE LIFT AS WELL AS ABUNDANT MOISTURE AND
INSTABILITY TO THE AREA. STORMS ARE EXPECTED TO SLOWLY WEAKEN
AND PUSH NORTHEAST THROUGH THE NIGHT.

A FEW REPORTS OF DAMAGING WINDS...LARGE HAIL...AND HEAVY RAINFALL
CAN BE EXPECTED FOR THE REST OF TONIGHT.

TORNADOES ARE NO EXPECTED FOR THE REST OF TONIGHT.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT THURSDAY MAY 30.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...90 PERCENT.

OTHER HAZARDOUS WEATHER...
HEAVY RAINFALL OF 1 TO 3 INCHES MAY CAUSE LOCALIZED
FLOODING TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

THUNDERSTORM OUTLOOK...
SEVERE THUNDERSTORMS ARE LIKELY IN CENTRAL AND NORTHERN
OKLAHOMA ON THURSDAY AND FRIDAY...DURING THE AFTERNOON AND EVENING
HOURS ON BOTH DAYS. VERY LARGE HAIL...DAMAGING WINDS...AND TORNADOES
ARE POSSIBLE WITH SEVERE THUNDERSTORMS THURSDAY AND FRIDAY.

STORM CHANCES WILL CONTINUE SATURDAY AND SATURDAY NIGHT ACROSS
MAINLY SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS...THEN RETURN
TO PARTS OF THE AREA MONDAY AND TUESDAY.

OTHER HAZARDOUS WEATHER...
VERY HEAVY RAINFALL AND LOCALIZED FLOODING WILL BE A POSSIBILITY
WITH STORMS THURSDAY THROUGH SATURDAY NIGHT.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT
5 AM THURSDAY.

CMS/MBS

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
945 PM CDT WED MAY 29 2013

OKZ011-012-017-018-300345-
KINGFISHER OK-BLAINE OK-GARFIELD OK-MAJOR OK-
945 PM CDT WED MAY 29 2013

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN KINGFISHER...NORTHERN
BLAINE...GARFIELD AND SOUTHEASTERN MAJOR COUNTIES UNTIL 1045 PM
CDT...

AT 942 PM CDT...STRONG THUNDERSTORMS WERE ALONG A LINE EXTENDING FROM
3 MILES NORTH OF AMES TO HITCHCOCK TO 3 MILES NORTH OF THOMAS...
MOVING NORTHEAST AT 40 MPH.

HAZARDS INCLUDE...
HAIL UP TO THE SIZE OF NICKELS...
WIND GUSTS TO 50 MPH...
MINOR FLOODING IN AREAS OF POOR DRAINAGE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MONITOR THE WEATHER SITUATION CLOSELY AND BE ALERT FOR THREATENING
WEATHER CONDITIONS.

&&

LAT...LON 3633 9751 3597 9796 3583 9863 3585 9863
      3597 9839 3633 9822 3660 9749
TIME...MOT...LOC 0242Z 242DEG 36KT 3629 9821 3599 9834 3580 9874

WR

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
955 PM CDT WED MAY 29 2013

OKZ041-046-047-050-051-300345-
MARSHALL OK-JOHNSTON OK-LOVE OK-MURRAY OK-CARTER OK-
955 PM CDT WED MAY 29 2013

...SIGNIFICANT WEATHER ADVISORY FOR MARSHALL...JOHNSTON...CENTRAL
LOVE...CENTRAL MURRAY AND EASTERN CARTER COUNTIES UNTIL 1045 PM
CDT...

AT 951 PM CDT...A STRONG THUNDERSTORM WAS LOCATED NEAR OAKLAND...
MOVING NORTH AT 40 MPH.

HAZARDS INCLUDE...
HAIL UP TO ONE-HALF INCH DIAMETER...
POTENTIALLY SEVERE WINDS GUSTING OVER 55 MPH...

LAT...LON 3385 9717 3392 9721 3386 9726 3385 9733
      3388 9733 3382 9739 3463 9705 3457 9686
      3449 9684 3449 9653 3383 9670 3382 9676
      3387 9680 3385 9687 3395 9691 3396 9699
      3385 9701 3385 9709 3382 9705 3382 9720
TIME...MOT...LOC 0251Z 195DEG 35KT 3410 9684

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1001 PM CDT WED MAY 29 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 PM     HAIL             3 N CORN                35.42N 98.78W
05/29/2013  E1.50 INCH       WASHITA            OK   PUBLIC

&&

RBARNES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1036 PM CDT WED MAY 29 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 PM     HAIL             1 ESE WEATHERFORD       35.52N 98.69W
05/29/2013  E1.00 INCH       CUSTER             OK   TRAINED SPOTTER

&&

MDAY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
1041 PM CDT WED MAY 29 2013

OKZ041-046-047-051-300430-
MARSHALL OK-JOHNSTON OK-MURRAY OK-CARTER OK-
1041 PM CDT WED MAY 29 2013

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN MARSHALL...JOHNSTON...
SOUTHEASTERN MURRAY AND SOUTHEASTERN CARTER COUNTIES UNTIL 1130 PM
CDT...

AT 1038 PM CDT...A STRONG THUNDERSTORM WAS LOCATED NEAR RUSSETT...
MOVING NORTH AT 55 MPH.

HAZARDS INCLUDE...
HAIL UP TO THE SIZE OF NICKELS...
MINOR FLOODING IN AREAS OF POOR DRAINAGE...
FREQUENT CLOUD TO GROUND LIGHTNING...

LAT...LON 3421 9644 3409 9676 3408 9728 3452 9702
      3450 9661 3444 9651 3442 9651 3442 9648
      3439 9643
TIME...MOT...LOC 0338Z 201DEG 49KT 3421 9683

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1042 PM CDT WED MAY 29 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1035 PM     TSTM WND GST     ARDMORE                 34.17N 97.13W
05/29/2013  M66 MPH          CARTER             OK   ASOS

&&

MDAY