000
ACUS11 KWNS 302339
SWOMCD
SPC MCD 302339
OKZ000-TXZ000-310115-

MESOSCALE DISCUSSION 1502
NWS STORM PREDICTION CENTER NORMAN OK
0639 PM CDT WED JUL 30 2014

AREAS AFFECTED...SWRN/CNTRL OK...WRN N TX

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 302339Z - 310115Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...SCATTERED TSTMS CAPABLE OF ISOLATED DAMAGING WIND AND
PERHAPS A TORNADO ARE POSSIBLE THIS EVENING. COVERAGE IS EXPECTED TO
INSUFFICIENT FOR WW ISSUANCE...BUT TRENDS WILL CONTINUE TO BE
MONITORED.

DISCUSSION...AT 2330Z...TSTMS WERE INCREASING IN CNTRL OK ALONG AN
ADVANCING COLD FRONT AND IN THE VICINITY OF A WEAK SFC LOW NOTED W
OF CHK. THIS ACTIVITY IS BEING AIDED BY ASCENT AHEAD OF A VORT MAX
MOVING ACROSS NRN OK AND SHOULD CONTINUE INTO THE EVENING. DESPITE
WEAK LAPSE RATES ACROSS THE REGION...A VERY MOIST BOUNDARY LAYER AND
MODEST WARMING HAS ALLOWED MLCAPE TO RISE TO 500-1500 J/KG.
MEANWHILE...FAVORABLE VEERING LOW-LEVEL WIND PROFILES...AS NOTED IN
THE OUN VWP...ARE RESULTING IN EFFECTIVE HELICITY VALUES OF 200-300
M2/S2...SUFFICIENT FOR AT LEAST WEAKLY ROTATING STORMS. AS A
RESULT...THERE IS SOME RISK OF DAMAGING WIND AND PERHAPS A TORNADO
ACROSS CNTRL/SRN OK...THOUGH THE AFOREMENTIONED WEAK LAPSE RATES
WILL TEND TO LIMIT CONVECTIVE INTENSITY AND COVERAGE OF ANY SEVERE
TSTMS IS EXPECTED TO REMAIN LIMITED.

FURTHER SOUTH ACROSS WRN N TX...STRONGER HEATING HAS RESULTED IN
GREATER INSTABILITY...WITH PERHAPS A GREATER CONDITIONAL RISK OF
SEVERE STORMS COMPARED TO AREAS FURTHER NORTH. HOWEVER...THIS AREA
IS FURTHER REMOVED FROM LARGE-SCALE ASCENT AND CONVERGENCE IS NOT
PARTICULARLY STRONG...WHICH WILL TEND TO LIMIT STORM COVERAGE IN
THIS AREA.

DUE TO LIMITED CONFIDENCE IN GREATER SEVERE COVERAGE...WW ISSUANCE
IS CONSIDERED UNLIKELY AT THIS TIME...BUT TRENDS WILL BE CLOSELY
MONITORED FOR AN UPTICK IN ORGANIZATION WITH ONGOING ACTIVITY AND
ANY ADDITIONAL INITIATION FURTHER SOUTH.

..DEAN/MEAD.. 07/30/2014

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

ATTN...WFO...FWD...OUN...

LAT...LON   33419993 34399941 35239867 35569817 35499765 35189711
            34709691 34449694 34109745 33769767 33439866 33419993