ZCZC SPCSWOMCD ALL
ACUS11 KWNS 191802 
SPC MCD 191802 
OKZ000-TXZ000-192000-

MESOSCALE DISCUSSION 0697
NWS STORM PREDICTION CENTER NORMAN OK
0102 PM CDT TUE MAY 19 2015

AREAS AFFECTED...NWRN TX INTO SWRN OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 191802Z - 192000Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...STORMS EXPECTED TO DEVELOP AND INTENSIFY FROM NWRN TX INTO
SWRN AND SCNTRL OK NEXT FEW HOURS. LARGE HAIL...DAMAGING WIND AND A
FEW TORNADOES WILL BE POSSIBLE. TRENDS ARE BEING MONITORED FOR
POSSIBLE WW.

DISCUSSION...A QUASI-STATIONARY FRONT EXTENDS FROM SRN OK WWD INTO
THE SRN TX PANHANDLE. RICH LOW-LEVEL MOISTURE HAS RETURNED NWD
THROUGH WARM SECTOR WHERE LOW 70S F DEWPOINTS RESIDE. BREAKS IN
MULTI-LAYER CLOUDS HAVE CONTRIBUTED TO DESTABILIZATION WHERE LATEST
OBJECTIVE ANALYSIS INDICATE MODERATE INSTABILITY WITH MLCAPE FROM
500-1000 J/KG OVER SWRN OK TO AROUND 1500-2000 J/KG OVER NWRN TX.
STORMS CONTINUE DEVELOPING IN VICINITY OF WARM FRONT WHERE SOME
MARGINAL SUPERCELL STRUCTURES HAVE BEEN OBSERVED. AS THE BOUNDARY
LAYER CONTINUES TO DESTABILIZE...ADDITIONAL STORMS WILL LIKELY
DEVELOP IN WARM SECTOR AND ONGOING STORMS MAY INTENSIFY. LATEST VWP
DATA SHOW 0-1 KM STORM RELATIVE HELICITY AROUND 200 M2/S2 NEAR AND
JUST SOUTH OF WARM FRONT ALONG WITH 30-40 KT EFFECTIVE BULK SHEAR. A
WEAKNESS IN WIND ABOVE 5 KM EXISTS...BUT SOME INCREASE MAY OCCUR AS
UPPER JET SWINGS THROUGH BASE OF UPPER TROUGH AND INTO THE SRN/CNTRL
HIGH PLAINS. RICH MOISTURE AND SUFFICIENTLY LARGE 0-2 KM HODOGRAPHS
WILL SUPPORT A THREAT OF LOW-LEVEL MESOCYCLONES AND A FEW
TORNADOES...ESPECIALLY FROM SWRN OK INTO NWRN TX. OTHERWISE
SUPERCELLS WITH ISOLATED LARGE HAIL AND DAMAGING WIND GUSTS APPEAR
LIKELY AS STORMS INTENSIFY THIS AFTERNOON.

..DIAL/THOMPSON.. 05/19/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FWD...OUN...SJT...LUB...MAF...

LAT...LON   34809957 34879767 34069729 32969844 32500008 32910072
            33730019 34809957 

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