[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 211859
SWOMCD
SPC MCD 211859 
IAZ000-WIZ000-212100-

MESOSCALE DISCUSSION 0798
NWS STORM PREDICTION CENTER NORMAN OK
0159 PM CDT FRI MAY 21 2004

AREAS AFFECTED...NRN IA INTO CNTRL/SRN WI

CONCERNING...SEVERE THUNDERSTORM WATCH 231...

VALID 211859Z - 212100Z

WW MAY NEED TO BE REPLACED WITH NEW TORNADO WATCH ACROSS PARTS OF
NORTH CENTRAL/NORTHEAST IOWA SHORTLY.

WEAK SHORT WAVE ASSOCIATED WITH MID-LEVEL JET STREAK NOW NOSING INTO
SOUTHERN MINNESOTA IS SUPPORTING EVOLUTION OF GROWING CLUSTER OF
STORMS ACROSS THE LA CROSSE AREA.  ACTIVITY APPEARS TO BE FOCUSED
ALONG BAROCLINIC ZONE IN THE 925 TO 850 MB LAYER...NORTH OF
CONVECTIVE OUTFLOW WHICH HAS REMAINED GENERALLY STATIONARY FROM THE
FORT DODGE AREA SOUTHEASTWARD TOWARD MOLINE.  BOUNDARY LAYER NORTH
OF OUTFLOW REMAINS GENERALLY COOL STABLE...LIMIT DAMAGING WIND
THREAT WITH CONVECTIVE SYSTEM AS IT PROGRESSES ACROSS CENTRAL
WISCONSIN...NORTHWEST OF MADISON NEXT COUPLE OF HOURS. HOWEVER...
RISK OF LARGE HAIL WILL PERSIST.

OTHERWISE...NEW CONVECTION CONTINUES TO DEVELOP/INTENSIFY NEAR
INTERSECTION OF OUTFLOW AND SYNOPTIC SURFACE FRONT...NEAR/EAST OF
FORT DODGE.  ACTIVITY APPEARS TO BE INCREASINGLY ROOTED IN VERY
MOIST UNSTABLE BOUNDARY LAYER WITH MEAN MIXED LAYER CAPE IN EXCESS
OF 2000 J/KG.  FURTHER INTENSIFICATION IS LIKELY NEXT COUPLE OF
HOURS AS IT DEVELOPS EAST SOUTHEASTWARD.  STRONGER 2 HOUR SURFACE
PRESSURE FALL CENTER HAS DEVELOPED ACROSS THE WATERLOO/ MARSHALLTOWN
AREA...WHERE HODOGRAPHS ARE BECOMING INCREASINGLY FAVORABLE FOR
TORNADIC SUPERCELLS.

..KERR.. 05/21/2004

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

ATTN...WFO...DVN...ARX...DMX...GRB...MKX...

43079358 43169262 43209167 42669101 41889212 42149364
42619414 

43339103 43949002 44338926 44168831 43748789 43068835
42908914 42719074 

WWWW