automated:SPC MD 1903 MD 1903 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SC...CNTRL NC AND VA MESOSCALE DISCUSSION 1903 NWS STORM PREDICTION CENTER NORMAN OK 0632 PM CDT SAT SEP 21 2013 AREAS AFFECTED...SC...CNTRL NC AND VA CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY VALID 212332Z - 220200Z PROBABILITY OF WATCH ISSUANCE...5 PERCENT SUMMARY...A FEW LOW TOPPED THUNDERSTORMS COULD PRODUCE LOCALLY STRONG WIND GUSTS THIS EVENING. IN ADDITION...AN ISOLATED BRIEF WEAK TORNADO CANNOT BE RULED OUT. HOWEVER...OVERALL THREAT AND COVERAGE IS EXPECTED TO BE TOO LOW FOR A WATCH. DISCUSSION...SURFACE ANALYSIS SHOWS A LOW OVER NWRN SC WITH SFC TROUGH EXTENDING NEWD ACROSS CNTRL VA. WEAK PRESSURE FALLS WERE NOTED NEAR THE SFC LOW...AND ACROSS VA WHERE A N-S ORIENTED LINE OF CONVECTION HAS FORMED...PRESUMABLY ALONG THE LEADING EDGE OF WARM ADVECTION ABOVE THE SURFACE. INSTABILITY ACROSS THE ENTIRE REGION CONTINUES TO BE WEAK...WITH ECHO TOPS GENERALLY IN THE 15-20K FT RANGE. ALMOST NO LIGHTNING WAS OCCURRING AS OF 2330Z. HOWEVER...FORCING ALONG VARIOUS WEAK FRONTAL WAVES FROM NWRN SC INTO VA HAVE RESULTED IN A FEW AREAS OF ENHANCED REFLECTIVITY AND TRANSIENT WEAK SHEAR COUPLETS. GIVEN THE RELATIVELY COOL SURFACE AIR MASS...AN UPWARD TREND IN INTENSITY IS NOT ANTICIPATED...BUT A FEW STRONG WIND GUSTS WILL REMAIN POSSIBLE...OR EVEN A WEAK BRIEF TORNADO EITHER WITH ACTIVITY NEAR THE FRONT OR WITH THE PRE-FRONTAL STORMS OVER ERN VA WHERE LOW LEVEL SHEAR IS STRONGEST. ..JEWELL/MEAD.. 09/21/2013 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...LWX...RAH...ILM...RNK...CAE...GSP... LAT...LON 34148227 34478263 34888247 36158041 37317906 38927783 39027742 39017697 38837673 38337643 37297606 36517615 36077653 35627696 34887796 34307937 34038083 34148227 Read more

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