[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 292235
SWOMCD
SPC MCD 292233 
NCZ000-SCZ000-300030-

MESOSCALE DISCUSSION 2147
NWS STORM PREDICTION CENTER NORMAN OK
0533 PM CDT SUN AUG 29 2004

AREAS AFFECTED...PORTIONS ERN NC

CONCERNING...SEVERE THUNDERSTORM WATCH 796...

VALID 292233Z - 300030Z

POTENTIAL FOR SUPERCELLS AND BRIEF/SMALL TORNADOES CONTINUES NE OF
CENTER OF GASTON AND SHOULD GRADUALLY SPREAD NEWD ACROSS NERN NC
THROUGH THIS EVENING.  POTENTIAL WILL END FROM SW-NE ACROSS REGION
AS CENTER OF SYSTEM MOVES NEWD OVER ERN NC.  AREAS NE OF WW 796 WILL
BE MONITORED FOR POSSIBLE ADDITIONAL/REPLACEMENT WW.  MEANWHILE WW
796 SHOULD BE CLEARED FROM SW-NE WITH PASSAGE OF CYCLONE CORE.

AVAILABLE VWP AND MODIFIED FCST SOUNDINGS SUGGEST FAVORABLE VERTICAL
SHEAR PROFILE WILL CONTINUE ACROSS NERN QUADRANT OF GASTON.  MOST
FAVORED AREA BASED ON SFC MESOANALYSIS WILL BE INVOF AXIS OF
STRONGEST PRESSURE FALLS THAT EXTENDS FROM TC CENTER NNEWD NEAR THE
LINE LBT...POB...LHZ.  ISALLOBARIC AXIS CORRESPONDS WELL TO
PRONOUNCED/QUASISTATIONARY SFC TROUGH/WIND SHIFT LINE...WHERE MAXIMA
OF 0-1 KM SHEAR...0-1 KM SRH AND BOUNDARY LAYER CONVERGENCE EACH ARE
INDICATED.  ANY DISCRETE STORM INTERACTING WITH THIS BOUNDARY MAY
DEVELOP/STRENGTHEN THEIR MESOCYCLONES AND ENHANCED TORNADO POTENTIAL
FOR AN HOUR OR TWO BEFORE MOVING INTO MORE WEAKLY SHEARED
ENVIRONMENT FARTHER W. MLCAPE VARIES FROM ABOUT 400-1000 J/KG
ACROSS MOST OF ERN NC NE OF CENTER...WITH AXIS ALSO LOCATED VERY
CLOSE TO PRESSURE FALL/TROUGH LINE.

BUOYANCY SHOULD GRADUALLY DIMINISH THROUGH REMAINDER EVENING BECAUSE
OF WEAK DIABATIC COOLING...HOWEVER SFC BASED PARCELS WILL REMAIN AT
LEAST MARGINALLY UNSTABLE FOR A FEW MORE HOURS IN ENVIRONMENT WITH
VERY LOW LCL.  MEANWHILE...AS CYCLONE CENTER APCHS...VERTICAL SHEAR
WILL INCREASE OVER AREA NE OF WW.  THESE OFFSETTING FACTORS SHOULD
YIELD TORNADO THREAT THERE SIMILAR TO OR SLIGHTLY BELOW PRESENT
PROBABILITY WITHIN WW.

..EDWARDS.. 08/29/2004

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

ATTN...WFO...MHX...RAH...ILM...CAE...

33237865 34638017 36337828 34967676 

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