MESOSCALE DISCUSSION 1940 NWS STORM PREDICTION CENTER NORMAN OK 1245 PM CDT SAT OCT 05 2013 AREAS AFFECTED...PORTIONS OF CNTRL TX NEWD INTO SERN OK CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY VALID 051745Z - 052015Z PROBABILITY OF WATCH ISSUANCE...5 PERCENT SUMMARY...ISOLATED MARGINALLY SVR HAIL CANNOT BE RULED OUT THIS AFTERNOON. A WW WILL NOT BE NEEDED. DISCUSSION...MODEST MID-LEVEL MOISTENING IS OCCURRING ATOP A SFC COLD DOME THAT CONTINUES TO EXPAND SEWD ACROSS PARTS OF CNTRL/SRN TX AND AR. THIS IS IN ASSOCIATION WITH A LOBE OF ASCENT PRECEDING A NE/SW-SHEARED IMPULSE ENTERING THE SRN HIGH PLAINS OF TX PER RECENT WATER VAPOR IMAGERY...WHICH IS ENCOURAGING THE DEVELOPMENT OF ANAFRONTAL CONVECTION FROM CNTRL TX NEWD INTO SERN OK. THIS ACTIVITY IS ROOTED ALONG/ABOVE THE NWWD-SLOPING FRONTAL SFC -- I.E. ABOVE THE 850-MB LEVEL PER 12Z RAOBS FROM OUN AND FWD. MODESTLY STEEP MID-LEVEL LAPSE RATES BETWEEN 700 AND 550 MB ARE CONTRIBUTING TO AROUND 1000 J/KG OF MUCAPE PER THE OBSERVED SOUNDINGS. AND...WITH ENHANCED MID-LEVEL FLOW GLANCING THE AREA IN ASSOCIATION WITH THE IMPULSE...30-40 KT OF EFFECTIVE BULK SHEAR MAY SUPPORT ISOLATED INSTANCES OF A FEW SUSTAINED AND STRONG ELEVATED THUNDERSTORMS. ISOLATED MARGINALLY SVR HAIL CANNOT BE RULED OUT. HOWEVER...A RELATIVE WARM LAYER CENTERED AROUND 500-MB WILL REDUCE THE MAGNITUDE OF MUCAPE AMIDST ONLY MODEST FORCING FOR ASCENT TO REDUCE THE OVERALL CONVECTIVE VIGOR. FURTHERMORE...THE ABSENCE OF STRONGER FORCING FOR ASCENT AND THE ELEVATED NATURE OF CONVECTION WILL PLACATE THE OVERALL SVR POTENTIAL.
Posted on: Sat, 05 Oct 2013 19:39:25 +0000
Trending Topics
Recently Viewed Topics
© 2015