MESOSCALE DISCUSSION 0366
NWS STORM PREDICTION CENTER NORMAN OK
0640 PM CDT SAT APR 18 2015

AREAS AFFECTED…PORTIONS OF TEXAS

CONCERNING…SEVERE THUNDERSTORM WATCH 72…76…

VALID 182340Z – 190115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
72…76…CONTINUES.

SUMMARY…AN EVOLVING MESOSCALE CONVECTIVE SYSTEM WILL CONTINUE
SPREADING EWD ACROSS PORTIONS OF CNTRL TX…WITH DMGG WIND GUSTS AND
SVR HAIL EXPECTED.

DISCUSSION…CONVECTION HAS CONGEALED INTO A FORWARD-PROPAGATING MCS
ACROSS PARTS OF CNTRL TX AND WILL CONTINUE SPREADING EWD TOWARD THE
INTERSTATE 35 CORRIDOR INCLUDING THE DFW METROPLEX AND WACO. STEEP
TROPOSPHERIC LAPSE RATES SUPPORTING 1500-2000 J/KG OF MLCAPE COUPLED
WITH 30-45 KT OF DEEP SHEAR ORIENTED LARGELY ORTHOGONAL TO THE
LEADING CONVECTIVE LINE WILL CONTINUE TO SUPPORT SVR WIND/HAIL. THE
LARGE HAIL POTENTIAL MAY BE SOMEWHAT GREATER WITH TRAILING SUPERCELL
STRUCTURES ON THE SRN FLANK OF THE EVOLVING COLD POOL AND FARTHER S
WITH MORE DISCRETE CONVECTION ACROSS PARTS OF THE EDWARDS PLATEAU
AND TX HILL COUNTRY. IN THE WAKE OF CONVECTIVELY STABILIZED AIR…
PROSPECTS FOR ADDITIONAL SFC-BASED CONVECTIVE DEVELOPMENT MAY
BE RELATIVELY LOW OWING TO INCREASED MLCINH — NOCTURNALLY ENHANCED.