Flash Flood Warning 10, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
400 AM CDT SUN JUN 12 2005

.DISCUSSION...
RISK OF SEVERE WX AND FLOODING GET ALL THE ATTENTION THIS
MORNING. SYNOPTIC SETUP IS OMINOUS FOR THIS LATE IN SEASON AS NEG-
TILT TROF DRIVES E INTO PLAINS...BUT MESOSCALE FACTORS AND TIMING
ISSUES STILL LEAD TO A LOT OF UNCERTAINTY AS TO HOW THINGS WILL
UNFOLD. ONGOING CONVECTION ACROSS KS...NW OK...AND PANHANDLES HAS
NOT HAD MUCH SUCCESS IN MOVING OR DEVELOPING S OR SE SO FAR. IF
THIS TREND PERSISTS IT WILL BE A BAD SIGN FOR OK AND N TX. OUTFLOW
BOUNDARY CURRENTLY EXPECTED TO HANG UP NEAR OR NW OF THE I-44
CORRIDOR FROM CENTRAL OK SW INTO NW TX OR FAR SW OK BY
AFTERNOON...AND MAY LIFT BACK N ACROSS THE PANHANDLE IN WAKE OF
THE DYING MCS.

VIRTUALLY ALL OF THE MODELS ARE SUSPECTED OF HAVING A POOR
DEPICTION OF MESOSCALE FEATURES THAT WILL PLAY OUT LATER TODAY.
THESE INCLUDE SFC BOUNDARY LOCATIONS...MID/UPPER JET STRUCTURE...
LOW-LEVEL MOISTURE... AND THUS INSTABILITY. POCKET OF LOWER SFC
DEWPOINTS THAT SEVERAL MODELS PULL N ACROSS TX/OK IS HIGHLY
SUSPECT...THUS MODEL INSTABILITY MAY WELL BE UNDERFORECAST. COULD
EASILY SEE SBCAPES OF 4000 J/KG OR MORE BY LATE AFTERNOON. NOSE OF
STRONG W/NW UPPER JET IS LIKELY TO SWING AROUND BASE OF NEG-TILT
TROF AND PUNCH FARTHER E INTO TX OK BY THIS EVENING. THEREFORE
MEAN-LAYER SHEAR ALSO MAY BE UNDERDONE BY MODELS. SO... WHEREVER
DYNAMIC FORCING ENCOUNTERS UNMODIFIED LOW-LEVEL AIR OR THE
NORTHERN BOUNDARY THEREOF...WE THINK THERE IS A POTENTIAL FOR
WELL-ORGANIZED SUPERCELLS AND AN ATTENDANT RISK OF GIANT HAIL AND
PERHAPS STRONG LONG-TRACK TORNADOES. THIS RISK WILL BE MAXIMIZED
NEAR ANY EXISTING LOW-LEVEL BOUNDARIES...WHICH AT THIS TIME WE
FAVOR TO BE FROM NEAR A DRYLINE TRIPLE POINT IN OR NEAR THE TX S
PLAINS NE-WARD ALONG THE RESIDUAL SFC OUTFLOW BOUNDARY ACROSS
PARTS OF NW TX/SW OK... AND PERHAPS FARTHER NE TOWARD
CENTRAL/NCENTRAL OK.

THIS ONE COULD GO EITHER WAY. WOULD NOT BE SURPRISED TO SEE
STRONG/VIOLENT TORNADOES...AND WOULD NOT BE SURPRISED IF EARLY OR
WIDESPREAD STORM INITIATION SHORT-CIRCUITS THE WHOLE THING. DUE TO
INHERENT UNCERTAINTIES WE WILL STAY WITH A MDT RISK THIS MORNING
BUT STRETCH IT FARTHER NE TO INCLUDE MORE OF CENTRAL/NCENTRAL OK.
HWO WILL BE STRONGLY BUT CAREFULLY WORDED TO EXPLAIN THE UNKNOWNS
AS BEST WE CAN.

ON HEAVY RAIN/FLOOD RISK...WE WILL LET THE CURRENT FLOOD WATCH
EXPIRE AT 12Z AS CURRENT CONVECTION SHOULD CONTINUE TO LOSE
INTENSITY AND ORGANIZATION THROUGH THE MORNING. BUT WE MAY WELL
HAVE TO GET BACK INTO SOME OF THESE AREAS WITH ANOTHER WATCH LATER
TODAY OR TONIGHT...PENDING DEVELOPMENT AND EVOLUTION OF CONVECTION
DURING THE DAY. CURRENT FORECAST IS FOR STORMS THIS EVENING
EVENTUALLY TO ORGANIZE UPSCALE INTO SOME FORM OF MCS...MOST LIKELY
LINEAR GIVEN THE STRONG DYNAMIC SUPPORT...AND MARCH E ACROSS THE
AREA OVERNIGHT.

NO CHANGES WILL BE MADE THIS MORNING TO GRIDS BEYOND DAY 2...AS
ALL EFFORTS ARE BROUGHT TO BEAR ON THE NEAR-TERM CONVECTIVE HAZARDS.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  89  68  91  67 /  30  70  20  30
HOBART OK         89  67  91  66 /  60  70  20  30
WICHITA FALLS TX  94  70  95  70 /  30  60  20  20
GAGE OK           83  63  89  58 /  60  70  10  30
PONCA CITY OK     87  68  89  65 /  50  70  20  30
DURANT OK         92  73  95  73 /  20  40  20  20

&&

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

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