[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 202331
SWOMCD
SPC MCD 202330 
SDZ000-NEZ000-210100-

MESOSCALE DISCUSSION 1744
NWS STORM PREDICTION CENTER NORMAN OK
0630 PM CDT TUE JUL 20 2004

AREAS AFFECTED...SERN SD THROUGH NERN NEB

CONCERNING...TORNADO WATCH 657...

VALID 202330Z - 210100Z

CORRECTED FOR TYPE OF BOX REFERENCE

THREAT FOR LARGE HAIL...MICROBURSTS AND POSSIBLY ISOLATED TORNADOES
EXPECTED TO PERSIST ANOTHER FEW HOURS.

EARLY THIS EVENING SCATTERED STORMS THAT DEVELOPED ALONG A SURFACE
BOUNDARY FROM SERN SD SWD THROUGH NERN NEB CONTINUE SLOWLY EAST.
MANY OF THE STORMS HAVE...SO FAR...NOT BEEN VERY PERSISTENT...MOST
LIKELY DUE TO MARGINAL CLOUD LAYER SHEAR WHICH IS PROMOTING OUTFLOW
DOMINANCE. DOWNSTREAM FROM THIS ACTIVITY...THE ATMOSPHERE REMAINS
STRONGLY UNSTABLE WITH MLCAPE AROUND 3500 J/KG ALONG WITH A MOIST
BOUNDARY LAYER...LOWER LCLS AND STRONGER LOW LEVEL SHEAR. HOWEVER...
OBJECTIVE ANALYSIS DATA ALSO SHOW A STRONGER CAP ACROSS FAR SERN SD
AND EXTREME NE NEB. GIVEN THE SLOW STORM MOTIONS...IT REMAINS
QUESTIONABLE WHETHER THE STORMS WILL SURVIVE INTO THE MORE FAVORABLE
ENVIRONMENT BEFORE THE ONSET OF NOCTURNAL COOLING FURTHER
STRENGTHENS THE CAP.

..DIAL.. 07/20/2004

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

ATTN...WFO...FSD...OAX...ABR...LBF...

42069953 44369877 44469664 43329667 41789701 

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