[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 081927
SWOMCD
SPC MCD 081927 
IAZ000-NEZ000-SDZ000-082200-

MESOSCALE DISCUSSION 0593
NWS STORM PREDICTION CENTER NORMAN OK
0227 PM CDT SAT MAY 08 2004

AREAS AFFECTED...SW THROUGH ERN NEB AND CNTRL IA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 081927Z - 082200Z

SWRN THROUGH CNTRL AND ERN NEB AND CNTRL IA ARE BEING MONITORED FOR
THUNDERSTORM INITIATION BY 22Z-23Z. ONCE STORMS DEVELOP...THEY
SHOULD RAPIDLY BECOME SEVERE WITH ISOLATED LARGE HAIL AND DAMAGING
WIND GUSTS THE PRIMARY THREATS. ONCE INITIATION APPEARS IMMINENT...A
WW WILL BE ISSUED.

THIS AFTERNOON A STATIONARY FRONT PARTIALLY REINFORCED BY CONVECTIVE
OUTFLOW EXTENDS THROUGH CNTRL IA WWD THROUGH E CNTRL NEB THEN SWWD
TO A WEAK SURFACE LOW IN SW NEB. THE ATMOSPHERE S OF THIS BOUNDARY
IS BECOMING QUITE UNSTABLE WITH MLCAPE FROM 2000 TO 2500 J/KG IN
WARM SECTOR ACROSS SERN NEB THROUGH SW IA. THE ATMOSPHERE STILL
APPEARS TO BE CAPPED IN THIS REGION AND THIS IS PROVIDING
UNCERTAINTY WITH REGARD TO WHEN STORMS WILL DEVELOP. LATEST
OBJECTIVE ANALYSIS SHOWS THE CAP WEAKENING AS THE BOUNDARY LAYER
CONTINUES TO WARM...AND THE CAP MAY BECOME SUFFICIENTLY WEAK FOR
STORMS TO INITIATE BY LATE AFTERNOON OR EARLY EVENING. WV IMAGERY
ALSO SUGGESTS AN AREA OF MID/UPPER ASCENT ASSOCIATED WITH A WEAK
SHORTWAVE TROUGH MAY BE SPREADING INTO WRN NEB FROM ERN CO.

ONE AREA OF POSSIBLE INITIATION IS ACROSS ERN NEB THROUGH CNTRL IA
WHERE SSWLY LOW LEVEL FLOW IMPINGING ON THE BOUNDARY IS PROVIDING A
SOURCE OF ENHANCED LIFT. CONVERGENCE AND LIFT WILL INCREASE IN THIS
AREA TOWARD EVENING AS THE LOW LEVEL JET STRENGTHENS. ANOTHER
POSSIBLE AREA FOR INITIATION WILL BE NEAR THE SW PORTIONS OF THE
BOUNDARY ACROSS SW NEB WHERE DEEPER MIXING WILL LIKELY RESULT IN A
WEAKER CAP. THOUGH VERTICAL SHEAR PROFILES ARE MARGINAL...STORMS
THAT MOVE NEWD ALONG OR JUST N OF THE BOUNDARY WOULD ENCOUNTER
SUFFICIENT LOW LEVEL DIRECTIONAL SHEAR TO SUPPORT A THREAT FOR
SUPERCELLS.

..DIAL.. 05/08/2004

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

ATTN...WFO...DVN...ARX...DMX...FSD...OAX...GID...LBF...GLD...

42829212 41719220 41339359 41299483 41109711 40099960
40320055 41360004 42489820 43349442 

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