[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 211029
SWOMCD
SPC MCD 211028 
WIZ000-ILZ000-IAZ000-MNZ000-211200-

MESOSCALE DISCUSSION 1807
NWS STORM PREDICTION CENTER NORMAN OK
0528 AM CDT THU JUL 21 2005

AREAS AFFECTED...SE MN...SW WI...ERN IA...NW IL

CONCERNING...SEVERE THUNDERSTORM WATCH 654...

VALID 211028Z - 211200Z

CONTINUE WW.

SHORT WAVE IMPULSE IN THE 700-500 MB LAYER...NOW SHIFTING EAST OF
THE MID MISSOURI VALLEY...STILL APPEARS TO BE PRIMARY FORCING
MECHANISM FOR ONGOING CONVECTIVE CLUSTER.  HOWEVER...GRAVITY WAVE IS
AIDING LIFT OF MOIST POTENTIALLY VERY UNSTABLE LOW-LEVEL AIR AS IT
SURGES TOWARD THE EASTERN IOWA BORDER. DESPITE PRESENCE OF
RADIATIONAL/WEAK FRONTAL INVERSION AHEAD OF BOW SHAPED CONVECTIVE
LINE...EVAPORATIVE COOLING HAS BEEN AIDING DOWNWARD TRANSFER OF
MOMENTUM ASSOCIATED WITH 30 TO 50 KT JET INTO REAR OF CONVECTIVE
SYSTEM.  THIS LIKELY WILL REMAIN THE CASE...WITH ISOLATED LARGE HAIL
ALSO POSSIBLE...AS ACTIVITY PROGRESSES INTO THE LA CROSSE WI/DUBUQUE
AND DAVENPORT IA AREAS BY THE 12-13Z TIME FRAME

..KERR.. 07/21/2005

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

ATTN...WFO...ILX...MKX...DVN...ARX...MPX...DMX...

43419287 44099363 44649218 43869028 42638999 41589003
41029044 40889169 41409232 42699228 

WWWW